Gut bacteriome and mood disorders in women with PCOS.

STUDY QUESTION: How does the gut bacteriome differ based on mood disorders (MDs) in women with polycystic ovary syndrome (PCOS), and how can the gut bacteriome contribute to the associations between these two conditions? SUMMARY ANSWER: Women with PCOS who also have MDs exhibited a distinct gut bacteriome with reduced alpha diversity and a significantly lower abundance of Butyricicoccus compared to women with PCOS but without MDs. WHAT IS KNOWN ALREADY: Women with PCOS have a 4- to 5-fold higher risk of having MDs compared to women without PCOS. The gut bacteriome has been suggested to influence the pathophysiology of both PCOS and MDs. STUDY DESIGN, SIZE, DURATION: This population-based cohort study was derived from the Northern Finland Birth Cohort 1966 (NFBC1966), which includes all women born in Northern Finland in 1966. Women with PCOS who donated a stool sample at age 46 years (n = 102) and two BMI-matched controls for each case (n = 205), who also responded properly to the MD criteria scales, were included. PARTICIPANTS/MATERIALS, SETTING, METHODS: A total of 102 women with PCOS and 205 age- and BMI-matched women without PCOS were included. Based on the validated MD criteria, the subjects were categorized into MD or no-MD groups, resulting in the following subgroups: PCOS no-MD (n = 84), PCOS MD (n = 18), control no-MD (n = 180), and control MD (n = 25). Clinical characteristics were assessed at age 31 years and age 46 years, and stool samples were collected from the women at age 46 years, followed by the gut bacteriome analysis using 16 s rRNA sequencing. Alpha diversity was assessed using observed features and Shannon's index, with a focus on genera, and beta diversity was characterized using principal components analysis (PCA) with Bray-Curtis Dissimilarity at the genus level. Associations between the gut bacteriome and PCOS-related clinical features were explored by Spearman's correlation coefficient. A P-value for multiple testing was adjusted with the Benjamini-Hochberg false discovery rate (FDR) method. MAIN RESULTS AND THE ROLE OF CHANCE: We observed changes in the gut bacteriome associated with MDs, irrespective of whether the women also had PCOS. Similarly, PCOS MD cases showed a lower alpha diversity (Observed feature, PCOS no-MD, median 272; PCOS MD, median 208, FDR = 0.01; Shannon, PCOS no-MD, median 5.95; PCOS MD, median 5.57, FDR = 0.01) but also a lower abundance of Butyricicoccus (log-fold changeAnalysis of Compositions of Microbiomes with Bias Correction (ANCOM-BC)=-0.90, FDRANCOM-BC=0.04) compared to PCOS no-MD cases. In contrast, in the controls, the gut bacteriome did not differ based on MDs. Furthermore, in the PCOS group, Sutterella showed positive correlations with PCOS-related clinical parameters linked to obesity (BMI, r2=0.31, FDR = 0.01; waist circumference, r2=0.29, FDR = 0.02), glucose metabolism (fasting glucose, r2=0.46, FDR < 0.001; fasting insulin, r2=0.24, FDR = 0.05), and gut barrier integrity (zonulin, r2=0.25, FDR = 0.03). LIMITATIONS, REASONS FOR CAUTION: Although this was the first study to assess the link between the gut bacteriome and MDs in PCOS and included the largest PCOS dataset for the gut microbiome analysis, the number of subjects stratified by the presence of MDs was limited when contrasted with previous studies that focused on MDs in a non-selected population. WIDER IMPLICATIONS OF THE FINDINGS: The main finding is that gut bacteriome is associated with MDs irrespective of the PCOS status, but PCOS may also modulate further the connection between the gut bacteriome and MDs. STUDY FUNDING/COMPETING INTEREST(S): This research was funded by the European Union's Horizon 2020 Research and Innovation Programme under the Marie Sklodowska-Curie Grant Agreement (MATER, No. 813707), the Academy of Finland (project grants 315921, 321763, 336449), the Sigrid Jusélius Foundation, Novo Nordisk Foundation (NNF21OC0070372), grant numbers PID2021-12728OB-100 (Endo-Map) and CNS2022-135999 (ROSY) funded by MCIN/AEI/10.13039/501100011033 and ERFD A Way of Making Europe. The study was also supported by EU QLG1-CT-2000-01643 (EUROBLCS) (E51560), NorFA (731, 20056, 30167), USA/NIH 2000 G DF682 (50945), the Estonian Research Council (PRG1076, PRG1414), EMBO Installation (3573), and Horizon 2020 Innovation Grant (ERIN, No. EU952516). The funders did not participate in any process of the study. We have no conflicts of interest to declare. TRIAL REGISTRATION NUMBER: N/A.

Ethinylestradiol in combined hormonal contraceptive has a broader effect on serum proteome compared with estradiol valerate: a randomized controlled trial.

STUDY QUESTION: Does an estradiol-based combined oral contraceptive (COC) have a milder effect on the serum proteome than an ethinylestradiol (EE)-based COC or dienogest (DNG) only? SUMMARY ANSWER: The changes in serum proteome were multifold after the use of a synthetic EE-based COC compared to natural estrogen COC or progestin-only preparation. WHAT IS KNOWN ALREADY: EE-based COCs widely affect metabolism, inflammation, hepatic protein synthesis and blood coagulation. Studies comparing serum proteomes after the use of COCs containing EE and natural estrogens are lacking. STUDY DESIGN, SIZE, DURATION: This was a spin-off from a randomized, controlled, two-center clinical trial. Women (n = 59) were randomized to use either EE + DNG, estradiol valerate (EV) + DNG or DNG only continuously for 9 weeks. PARTICIPANTS/MATERIALS, SETTING, METHODS: Participants were healthy, young, white volunteer women. Serum samples were collected before and after 9 weeks of hormonal exposure. Samples from 44 women were available for analysis (EE + DNG n = 14, EV + DNG n = 16 and DNG only n = 14). Serum proteins were analyzed by quantitative, discovery-type label-free proteomics. MAIN RESULTS AND THE ROLE OF CHANCE: Altogether, 446 proteins/protein families with two or more unique peptides were detected and quantified. The number of proteins/families that altered over the 9-week period within the study groups was 121 for EE + DNG and 5 for EV + DNG, while no changes were detected for DNG only. When alterations were compared between the groups, significant differences were detected for 63 proteins/protein families, of which 58 were between the EE + DNG and EV + DNG groups. The most affected functions during the use of EE + DNG were the complement system, acute phase response signaling, metabolism and the coagulation system. The results were validated by fetuin-B and cortisol-binding globulin ELISA and sex hormone-binding globulin immunoassay. LARGE SCALE DATA: Data are available via ProteomeXchange with identifiers PXD033617 (low abundance fraction) and PXD033618 (high abundance fraction). LIMITATIONS, REASONS FOR CAUTION: The power analysis of the trial was not based on the proteomic analysis of this spin-off study. In the future, targeted proteomic analysis with samples from another trial should be carried out in order to confirm the results. WIDER IMPLICATIONS OF THE FINDINGS: The EE-based COC exerted a broader effect on the serum proteome than the EV-based COC or the DNG-only preparation. These results demonstrate that the effects of EE in COCs go far beyond the established endpoint markers of estrogen action, while the EV combination is closer to the progestin-only preparation. The study indicates that EV could provide a preferable option to EE in COCs in the future and signals a need for further studies comparing the clinical health outcomes of COCs containing EE and natural estrogens. STUDY FUNDING/COMPETING INTEREST(S): Funding for this researcher-initiated study was obtained from the Helsinki University Hospital research funds, the Hospital District of Helsinki and Uusimaa, the Sigrid Juselius Foundation, the Academy of Finland, the Finnish Medical Association, the University of Oulu Graduate School, the Emil Aaltonen Foundation, the Swedish Cultural Foundation in Finland, the Novo Nordisk Foundation, Orion Research Foundation and the Northern Ostrobothnia Regional Fund. The funders had no role in study design, data collection and analysis, publishing decisions or manuscript preparation. T.P. has received honoraria for lectures, consultations and research grants from Exeltis, Gedeon Richter, MSD, Merck, Pfizer, Roche, Stragen and Mithra Pharmaceuticals. O.H. occasionally serves on advisory boards for Bayer AG and Gedeon Richter and has designed and lectured at educational events for these companies. The other authors have nothing to disclose. O.H. occasionally serves on advisory boards for Bayer AG and Gedeon Richter and has designed and lectured at educational events for these companies. The other authors have nothing to disclose. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov NCT02352090. TRIAL REGISTRATION DATE: 27 January 2015. DATE OF FIRST PATIENT'S ENROLMENT: 1 April 2015.

Human pluripotent stem cell-derived cells endogenously expressing follicle-stimulating hormone receptors: modeling the function of an inactivating receptor mutation.

Follicle-stimulating hormone (FSH) is crucial in the development and regulation of reproductive functions. The actions of human FSH and its receptor (FSHR) and mutations therein have mainly been studied using in vivo models, primary cells, cancer cells and cell lines ectopically expressing the FSHR. To allow studies of endogenous FSHR function in vitro, we differentiated FSHR-expressing cells from human pluripotent stem cells. FSH stimulation of the wild-type (WT), but not the inactivating Finnish founder mutant (A189V) receptor, activated the canonical cyclic adenosine monophosphate (cAMP)-dependent signaling pathway and downstream mediators. To investigate protein-protein interaction partners of FSHR at resting state and upon FSH stimulation, we expressed FSHR in HEK293 cells followed by affinity purification mass spectrometry analyses. We found 19 specific high-confidence interacting proteins for WT FSHR and 14 for A189V FSHR, several of which have been linked to infertility. Interestingly, while only WT FSHR interacted with FSH, insulin-like growth factor 1 receptor (IGF1R), for example, interacted with both WT and A189V FSHR upon FSH stimulation. In conclusion, our protocol allows detailed studies of FSH action and disease modeling in human cells endogenously expressing FSHR.

BMI in childhood and adolescence is associated with impaired reproductive function-a population-based cohort study from birth to age 50 years.

STUDY QUESTION: What is the association between childhood and adolescent BMI and reproductive capacity in women? SUMMARY ANSWER: Adolescent girls with obesity had an increased risk of infertility and childlessness in adulthood independently of their marital status or the presence of polycystic ovary syndrome (PCOS). WHAT IS KNOWN ALREADY: Girls with obesity (BMI (kg/m2)>95th percentile) more often exhibit menstrual irregularities and infertility problems as compared to those with normal weight, and premenarcheal girls with obesity have an increased risk of childlessness and infertility in adulthood. Follow-up studies on the relation between childhood and adolescence growth patterns and fertility or parity throughout the reproductive life span are limited. STUDY DESIGN, SIZE, DURATION: A prospective, population-based cohort study (the Northern Finland birth cohort 1966) was performed with 5889 women born in 1966 and followed from birth to age 50 years. Postal questionnaires at ages 31 and 46 years addressed questions on reproductive capacity evaluated by decreased fecundability, need for infertility assessment and treatment by 46 years of age. Childlessness and number of children by age 50 years were recovered from registers. Women who did not report ever having attempted to achieve pregnancy (n = 1507) were excluded. The final study population included 4382 women who attempted to achieve pregnancy before age 46 years. PARTICIPANTS/MATERIALS, SETTING, METHODS: Data on BMI were collected by trained personnel at all stages. We assessed association with both prospectively measured BMI at various time points and with early adiposity phenotypes derived from linear mixed models including the timing and the BMI at adiposity peak (AP) and adiposity rebound (AR). Self-reported infertility assessments and treatments were assessed at ages 31 and 46 years. Data on deliveries were collected from the national birth register. Decreased fecundability was defined at age 31 years as time to achieve pregnancy over 12 months. Logistic regression analyses were conducted with adjustments for marital status, education level and smoking at age 31 years. Women with PCOS were excluded from stratification-based sensitivity analyses. Obesity at a specific age group was defined by having at least one BMI value above the 95th percentile during the related period. MAIN RESULTS AND THE ROLE OF CHANCE: BMI at the age of AR (5-7 years) was not associated with fertility outcomes after adjustments, but girls with AR <5.1 years had a higher risk of remaining childless compared to girls with AR over 5.1 years (adjusted odds ratio (OR): 1.45 (1.10-1.92)). At ages 7-10 and 11-15 years, obesity was associated with decreased fecundability (adjusted OR 2.05 (1.26-3.35) and 2.04 (1.21-3.44), respectively) and a lower number of children. At age 11-15 years, both overweight and obesity were associated with a higher risk of childlessness (adjusted OR 1.56 (1.06-2.27), 1.77 (1.02-3.07), respectively), even after excluding women with PCOS. Underweight at age 11-15 years was associated with an increased risk for infertility treatment (adjusted OR 1.55 (1.02-2.36)) and a tendency for an increased risk for infertility assessment (adjusted OR 1.43 (0.97-2.10)) after excluding women with PCOS. LIMITATIONS, REASON FOR CAUTION: Despite a high participation rate throughout the follow-up, some growth data for children over the different age groups were missing. Infertility outcomes were self-reported. A potential over-diagnosis of obesity may have reduced the significance of the association between childhood obesity and fertility outcomes, and the diagnosis of PCOS was self-reported. WIDER IMPLICATIONS OF THE FINDINGS: This study supports previous results showing that girls with obesity in late childhood and in adolescence displayed reduced fertility and an increased risk of remaining childless in adulthood, independently of marital history and PCOS in adulthood. These findings corroborate the body of evidence for a causal relation between early adiposity and the reproductive functions in women. We recommend reinforcing the prevention of obesity in school-age girls to reduce the risk of impaired reproductive functions. STUDY FUNDING/COMPETING INTEREST(S): NFBC1966 received financial support from University of Oulu Grant no. 65354, Oulu University Hospital Grant no. 2/97, 8/97, Ministry of Health and Social Affairs Grant no. 23/251/97, 160/97, 190/97, National Institute for Health and Welfare, Helsinki Grant no. 54121, Regional Institute of Occupational Health, Oulu, Finland Grant no. 50621, 54231. The Finnish Medical Foundation, the North Ostrobothnia Regional Fund, the Academy of Finland (project grants 315921, 104781, 120315, 129269, 1114194, 24300796), Center of Excellence in Complex Disease Genetics and SALVE, the Sigrid Juselius Foundation, Biocenter Oulu, University Hospital Oulu and University of Oulu (75617), Jalmari ja Rauha Ahokkaan säätiö, The Finnish Medical Foundation, Medical Research Center Oulu, National Institute for Health Research (UK). M. R. J., S. S. and R. N. received funding by the Academy of Finland (#268336) and the European Union's Horizon 2020 research and innovation program (under Grant agreement no. 633595 for the DynaHEALTH action and GA 733206 for LifeCycle). The funders had no role in study design, in the collection, analysis and interpretation of the data, in the writing of the article and in the decision to submit it for publication. The authors have no conflict of interest to disclose. TRIAL REGISTRATION NUMBER: N/A.

Age at adiposity rebound in childhood is associated with PCOS diagnosis and obesity in adulthood-longitudinal analysis of BMI data from birth to age 46 in cases of PCOS.

BACKGROUND: Adiposity rebound (AR), the second BMI rise in childhood at around the age of 6 years, is associated with obesity and metabolic alteration in later life. Given that polycystic ovary syndrome (PCOS) has a strong metabolic component, early life growth patterns could reveal a risk of PCOS. Thus, we aimed to investigate the associations between age at AR and PCOS diagnosis and BMI later in life. MATERIALS AND METHODS: This study is part of a prospective, population-based longitudinal study, where women with PCOS diagnosis by age 46 (n = 280) were compared with asymptomatic women (CTRLs, n = 1573). Weight and height data from birth to age 13 years, at age at menarche, and at ages 31 and 46 years were analyzed RESULTS: Women with PCOS had lower birth weight (3357 ± 477 vs. 3 445 ± 505 g, p < 0.001), earlier age at AR (5.2 ± 1.0 vs. 5.6 ± 0.90 years, p < 0.001) and higher BMI from AR onwards compared with controls. Early timing of AR was associated with PCOS diagnosis independently of BMI (OR 1.62, 95% Cl 1.37-1.92). Women with PCOS and early AR had higher BMI at 31 and 46 years when compared to controls with early AR. The age at AR did not associate with T levels at ages 31 or 46 years. CONCLUSIONS: Early AR was associated with PCOS diagnosis and high BMI in adulthood. Adolescent girls with early AR and persisting obesity should be screened for PCOS symptoms, such as persistent irregular cycles and hirsutism.

Overweight and obese but not normal weight women with PCOS are at increased risk of Type 2 diabetes mellitus-a prospective, population-based cohort study.

STUDY QUESTION: What are the respective roles of polycystic ovary syndrome (PCOS), long-term weight gain and obesity for the development of prediabetes or Type 2 diabetes mellitus (T2DM) by age 46 years? SUMMARY ANSWER: The risk of T2DM in women with PCOS is mainly due to overweight and obesity, although these two factors have a synergistic effect on the development of T2DM. WHAT IS KNOWN ALREADY: PCOS is associated with an increased risk of prediabetes and T2DM. However, the respective roles of PCOS per se and BMI for the development of T2DM have remained unclear. STUDY DESIGN, SIZE, DURATION: In a prospective, general population-based follow-up birth cohort 1966 (n = 5889), postal questionnaires were sent at ages 14 (95% answered), 31 (80% answered) and 46 years (72% answered). Questions about oligoamenorrhoea and hirsutism were asked at age 31 years, and a question about PCOS diagnosis at 46 years. Clinical examination and blood sampling were performed at 31 years in 3127 women, and at 46 years in 3280 women. A 2-h oral glucose tolerance test (OGTT) was performed at 46 years of age in 2780 women. PARTICIPANTS/MATERIALS, SETTING, METHODS: Women reporting both oligoamenorrhoea and hirsutism at age 31 years and/or diagnosis of PCOS by 46 years were considered as women with PCOS (n = 279). Women without any symptoms at 31 years and without PCOS diagnosis by 46 years were considered as controls (n = 1577). The level of glucose metabolism was classified according to the results of the OGTT and previous information of glucose metabolism status from the national drug and hospital discharge registers. MAIN RESULTS AND THE ROLE OF CHANCE: PCOS per se significantly increased the risk of T2DM in overweight/obese (BMI ≥ 25.0 kg/m2) women with PCOS when compared to overweight/obese controls (odds ratio: 2.45, 95% CI: 1.28-4.67). Normal weight women with PCOS did not present with an increased risk of prediabetes or T2DM. The increase in weight between ages 14, 31 and 46 years was significantly greater in women with PCOS developing T2DM than in women with PCOS and normal glucose tolerance, with the most significant increase occurring in early adulthood (between 14 and 31 years: median with [25%; 75% quartiles]: 27.25 kg [20.43; 34.78] versus 13.80 kg [8.55; 20.20], P < 0.001). LIMITATIONS, REASONS FOR CAUTION: The diagnosis of PCOS was based on self-reporting, and the questionnaire at 46 years did not distinguish between polycystic ovaries only in ultrasonography and the syndrome. Ovarian ultrasonography was not available to aid the diagnosis of PCOS. WIDER IMPLICATIONS OF THE FINDINGS: These results emphasize weight management already during adolescence and early adulthood to prevent the development of T2DM in women with PCOS, as the period between 14 and 31 years seems to be a crucial time-window during which the women with PCOS who are destined to develop T2DM by 46 years of age experience a dramatic weight gain. Furthermore, our results support the view that, particularly in times of limited sources of healthcare systems, OGTT screening should be targeted to overweight/obese women with PCOS rather than to all women with PCOS. STUDY FUNDING/COMPETING INTERESTS: Finnish Medical Foundation; North Ostrobothnia Regional Fund; Academy of Finland (project grants 104781, 120315, 129269, 1114194, 24300796, Center of Excellence in Complex Disease Genetics and SALVE); Sigrid Juselius Foundation; Biocenter Oulu; University Hospital Oulu and University of Oulu (75617); Medical Research Center Oulu; National Institute for Health Research (UK); National Heart, Lung, and Blood Institute (grant 5R01HL087679-02) through the STAMPEED program (1RL1MH083268-01); National Institute of Health/National Institute of Mental Health (5R01MH63706:02); ENGAGE project and grant agreement HEALTH-F4-2007-201413; EU FP7 EurHEALTHAgeing-277849 European Commission and Medical Research Council, UK (G0500539, G0600705, G1002319, PrevMetSyn/SALVE) and Medical Research Center, Centenary Early Career Award. The authors have no conflicts of interests. TRIAL REGISTRATION NUMBER: N/A.

Copy number variation analysis detects novel candidate genes involved in follicular growth and oocyte maturation in a cohort of premature ovarian failure cases.

STUDY QUESTION: Can spontaneous premature ovarian failure (POF) patients derived from population-based biobanks reveal the association between copy number variations (CNVs) and POF? SUMMARY ANSWER: CNVs can hamper the functional capacity of ovaries by disrupting key genes and pathways essential for proper ovarian function. WHAT IS KNOWN ALREADY: POF is defined as the cessation of ovarian function before the age of 40 years. POF is a major reason for female infertility, although its cause remains largely unknown. STUDY DESIGN, SIZE, DURATION: The current retrospective CNV study included 301 spontaneous POF patients and 3188 control individuals registered between 2003 and 2014 at Estonian Genome Center at the University of Tartu (EGCUT) biobank. PARTICIPANTS/MATERIALS, SETTING, METHODS: DNA samples from 301 spontaneous POF patients were genotyped by Illumina HumanCoreExome (258 samples) and HumanOmniExpress (43 samples) BeadChip arrays. Genotype and phenotype information was drawn from the EGCUT for the 3188 control population samples, previously genotyped with HumanCNV370 and HumanOmniExpress BeadChip arrays. All identified CNVs were subjected to functional enrichment studies for highlighting the POF pathogenesis. Real-time quantitative PCR was used to validate a subset of CNVs. Whole-exome sequencing was performed on six patients carrying hemizygous deletions that encompass genes essential for meiosis or folliculogenesis. MAIN RESULTS AND THE ROLE OF CHANCE: Eleven novel microdeletions and microduplications that encompass genes relevant to POF were identified. For example, FMN2 (1q43) and SGOL2 (2q33.1) are essential for meiotic progression, while TBP (6q27), SCARB1 (12q24.31), BNC1 (15q25) and ARFGAP3 (22q13.2) are involved in follicular growth and oocyte maturation. The importance of recently discovered hemizygous microdeletions of meiotic genes SYCE1 (10q26.3) and CPEB1 (15q25.2) in POF patients was also corroborated. LIMITATIONS, REASONS FOR CAUTION: This is a descriptive analysis and no functional studies were performed. Anamnestic data obtained from population-based biobank lacked clinical, biological (hormone levels) or ultrasonographical data, and spontaneous POF was predicted retrospectively by excluding known extraovarian causes for premature menopause. WIDER IMPLICATIONS OF THE FINDINGS: The present study, with high number of spontaneous POF cases, provides novel data on associations between the genomic aberrations and premature menopause of ovarian cause and demonstrates that population-based biobanks are powerful source of biological samples and clinical data to reveal novel genetic lesions associated with human reproductive health and disease, including POF. STUDY FUNDING/COMPETING INTEREST: This study was supported by the Estonian Ministry of Education and Research (IUT20-43, IUT20-60, IUT34-16, SF0180027s10 and 9205), Enterprise Estonia (EU30020 and EU48695), Eureka's EUROSTARS programme (NOTED, EU41564), grants from European Union's FP7 Marie Curie Industry-Academia Partnerships and Pathways (IAPP, SARM, |EU324509) and Horizon 2020 innovation programme (WIDENLIFE, 692065), Academy of Finland and the Sigrid Juselius Foundation.

Effect of controlled hypoglycaemia on sympathetic skin response in patients with Type 1 diabetes and control subjects.

AIM: To evaluate the quantity and mechanism of sudomotor function during euglycaemia and hypoglycaemia using sympathetic skin responses in patients with Type 1 diabetes and control subjects. METHODS: Sympathetic skin responses were measured in 16 patients with diabetes without neuropathy and in eight control subjects during euglycaemic and hypoglycaemic clamp. RESULTS: During hypoglycaemia, the number of repetitive synchronous sympathetic skin responses significantly increased in both groups (P<0.05), and this increase was significantly associated with the hypoglycaemia and sweating. CONCLUSIONS: During hypoglycaemia the number of repetitive synchronous sympathetic skin responses was related to increased sweating according to the hypoglycaemic symptom score. This is best explained by central nervous system reactions. The sympathetic skin responses of the patients with Type 1 diabetes had a weaker correlation with hypoglycaemia and its symptoms, which was possibly attributable to an adaptation or a dysfunction of the patients' sudomotor pathways.

Anti-Müllerian hormone: correlation with testosterone and oligo- or amenorrhoea in female adolescence in a population-based cohort study.

STUDY QUESTIONS: Can serum anti-Müllerian hormone (AMH) levels measured in female adolescents predict polycystic ovary syndrome (PCOS)-associated features in adolescence and early adulthood? SUMMARY ANSWER: AMH levels associated well with PCOS-associated features (such as testosterone levels and oligoamenorrhoea) in adolescence, but was not an ideal marker to predict PCOS-associated features in early adulthood. WHAT IS KNOWN ALREADY: Several studies have reported that there is a strong correlation between antral follicle count and serum AMH levels and that women with PCOS/PCO have significantly higher serum AMH levels than women with normal ovaries. Other studies have reported an association between AMH serum levels and hyperandrogenism in adolescence, but none has prospectively assessed AMH as a risk predictor for developing features of PCOS during adulthood. STUDY DESIGN, SIZE, DURATION: A subset of 400 girls was selected from the prospective population-based Northern Finland Birth Cohort 1986 (n = 4567 at age 16 and n = 4503 at age 26). The population has been followed from 1986 to the present. PARTICIPANTS/MATERIAL, SETTING, METHODS: At age 16, 400 girls (100 from each testosterone quartile: 50 with oligo- or amenorrhoea and 50 with a normal menstrual cycle) were selected at random from the cohort for AMH measurement. Metabolic parameters were also assessed at age 16 in all participants. Postal questionnaires enquired about oligo- or amenorrhoea, hirsutism, contraceptive use and reproductive health at ages 16 and 26. MAIN RESULTS AND ROLE OF CHANCE: There was a significant correlation between AMH and testosterone at age 16 (r = 0.36, P < 0.001). AMH levels at age 16 were significantly higher among girls with oligo- or amenorrhoea compared with girls with normal menstrual cycles (35.9 pmol/l [95% CI: 33.2;38.6] versus 27.7 pmol/l [95% CI: 25.0;30.4], P < 0.001). AMH at age 16 was higher in girls who developed hirsutism at age 26 compared with the non-hirsute group (31.4 pmol/l [95% CI 27.1;36.5] versus 25.8 pmol/l [95% CI 23.3;28.6], P = 0.036). AMH at age 16 was also higher in women with PCOS at age 26 compared with the non-PCOS subjects (38.1 pmol/l [95% CI 29.1;48.4] versus 30.2 pmol/l [95% CI 27.9;32.4], P = 0.044). The sensitivity and specificity of the AMH (cut-off 22.5 pmol/l) for predicting PCOS at age 26 was 85.7 and 37.5%, respectively. The addition of testosterone did not significantly improve the accuracy of the test. There was no significant correlation between AMH levels and metabolic indices at age 16. IMPLICATIONS, REASONS FOR CAUTION: AMH is related to oligo- or amenorrhoea in adolescence, but it is not a good marker for metabolic factors. The relatively low rate of participation in the questionnaire at age 26 may also have affected the results. AMH was measured in a subset of the whole cohort. AMH measurement is lacking international standardization and therefore the concentrations and cut-off points are method dependent. WIDER IMPLICATIONS FOR THE FINDINGS: Using a high enough cut-off value of AMH to predict which adolescents are likely to develop PCOS in adulthood could help to manage the condition from an early age due to a good sensitivity. However, because of its low specificity, it is not an ideal diagnostic marker, and its routine use in clinical practice cannot, at present, be recommended. STUDY FUNDINGS AND COMPETING INTERESTS: The study was funded by a grant from Wellcome Trust (089549/Z/09/Z) to H.L., S.F. and M.-R.J. Study funding was also received from Oulu University Hospital Research Funds, Sigrid Juselius Foundation and the Academy of Finland. None of the authors have any competing interest to declare.

Irregular menstruation and hyperandrogenaemia in adolescence are associated with polycystic ovary syndrome and infertility in later life: Northern Finland Birth Cohort 1986 study.

STUDY QUESTION: Do teenage girls with a history of menstrual irregularity and/or elevated androgen levels in adolescence exhibit an increased risk of polycystic ovary syndrome (PCOS) and/or infertility later on in adulthood? SUMMARY ANSWER: Our results suggest that menstrual irregularity and/or elevated androgen levels at 16 years are still associated with symptoms of PCOS at 26 years as well as infertility problems at 26 years but not with decreased pregnancy or delivery rates at 26 years. WHAT IS KNOWN ALREADY: Hyperandrogenaemia is associated with menstrual irregularity, hirsutism, acne and potentially higher risk for PCOS, but there are few follow-up studies investigating whether adolescent hyperandrogenaemia and/or menstrual irregularity are an early sign of PCOS. STUDY DESIGN, SIZE, DURATION: A prospective population-based cohort study was conducted using two postal questionnaires targeting girls in the Northern Finland Birth Cohort 1986 (NFBC1986, n = 4567). The NFBC1986 comprises all expected births from the year 1986 in the two northernmost provinces of Finland. Collection of the database was performed at the age of 16 and 26. The 16-year and 26-year questionnaires included one question about the regularity and length of the menstrual cycle. The 26-year questionnaire also included questions about symptoms of PCOS, reproduction and infertility problems. PARTICIPANTS, SETTING, METHODS: The response rates for the questionnaires were 80% (n = 3669) at 16 years and 50% (n = 2270) at 26 years. At 15-16 years, of 2448 girls, 709 (29%) girls reported menstrual irregularity (symptomatic girls) and 1739 (71%) had regular periods (non-symptomatic girls). After combining data from the two questionnaires a total of 2033 girls were included in the analyses. The χ(2) and Student's t-test was used to compare reproductive outcome and prevalence of clinical hyperandrogenaemia, PCOS and infertility at 26 years between the study groups. Univariate and multivariate logistic regression models were employed to estimate the association of menstrual irregularity at 16 years with clinical hyperandrogenaemia, PCOS and infertility at 26 years. MAIN RESULTS AND THE ROLE OF CHANCE: At follow-up, the proportion of symptomatic girls who had conceived at least once (68.0 versus 67.9%) and had delivered at least one child (25.7 versus 28.1%) was similar to the non-symptomatic women and the groups had similar miscarriage rates (11.6 versus 12.1%). Logistic regression analyses indicated that menstrual irregularity at 16 years was associated with an increased risk of menstrual irregularity [adjusted odds ratio (OR) 1.37, 95% confidence interval (CI) 1.00-1.88, P = 0.050], PCOS (adjusted OR 2.91, 95% CI 1.74-4.84, P < 0.001) and infertility problems (adjusted OR 2.07, 95% CI 1.16-3.76, P = 0.013) at 26 years. At 26 years, women with PCOS (P = 0.013), hirsutism (P = 0.001) and acne (P < 0.001) exhibited significantly higher values of free androgen index (FAI) at 16 years than control women. There was a significant linear trend in the higher FAI quartiles at 16 years towards higher prevalence of PCOS (P = 0.005), hirsutism (P < 0.001) and acne (P < 0.001) at 26 years. Only 10.5% of the girls with menstrual irregularity at 16 years had PCOS at 26 years. LIMITATIONS, REASONS FOR CAUTION: The diagnosis of menstrual irregularity was based on a self-reported questionnaire, thus introducing a risk of information bias in reporting the symptoms. Moreover, ovarian ultrasonography was not available to aid the diagnosis of PCOS and there was no clinical evaluation of hyperandrogenism. The relatively low rate of participation to the questionnaire at 26 years may also have biased the results. WIDER IMPLICATIONS OF THE FINDINGS: Our findings confirm that menstrual irregularity and/or elevated androgen levels are already present in adolescence in women with PCOS and infertility in later life, which strengthens the importance of early identification of menstrual irregularity. STUDY FUNDING/COMPETING INTERESTS: This work was supported by grants from the Finnish Medical Society Duodecim, the North Ostrobothnia Regional Fund, the Academy of Finland, the Sigrid Juselius Foundation, University Hospital Oulu and University of Oulu, the European Commission and the Medical Research Council, UK, Welcome Trust (089549/Z/09/Z). None of the authors have any conflict of interest.

Men homozygous for an inactivating mutation of the follicle-stimulating hormone (FSH) receptor gene present variable suppression of spermatogenesis and fertility.

Gonadal function is controlled by the two pituitary gonadotropins, luteinizing hormone (LH) and follicle-stimulating hormone (FSH). While LH mainly regulates gonadal steroidogenesis, FSH is considered essential for folliculogenesis in the female and spermatogenesis in the male. We recently discovered that an inactivating point mutation in the FSH receptor (R) gene causes a recessively inherited form of hypergonadotropic ovarian failure in homozygous females. This 566C-->T mutation, predicting an alanine to valine substitution, is located in exon 7 of the FSHR gene, in the region encoding the extracellular domain of the receptor molecule. Functional testing showed a clear-cut reduction in ligand binding and signal transduction by the mutated receptor. Hence, lack of FSH function is incompatible with ovarian follicular maturation and female fertility. In the male, FSH is generally considered essential for the pubertal initiation of spermatogenesis and maintenance of quantitatively normal sperm production in adults. We report here the first characterization of males homozygous for an inactivating FSHR mutation. They have variable degrees of spermatogenic failure, but, surprisingly, do not show azoospermia or absolute infertility. These results question the essential role of FSH for the initiation of spermatogenesis, and demonstrate that FSH is more important for female than for male fertility.

Anti-Mullerian hormone as a predictor of follicular reserve in ovarian insufficiency: special emphasis on FSH-resistant ovaries.

BACKGROUND: Anti-Müllerian hormone (AMH) is secreted by ovarian granulosa cells and its serum levels reflect ovarian follicle reserve. The main objective of this study was to test the use of AMH assay in identifying women with primary amenorrhea (PA) and existing follicles and to study follicle phase dependent AMH secretion. METHODS: Serum levels of AMH were measured in subjects with FSH-resistant ovaries (FSHRO, n= 12), primary ovarian insufficiency (POI) with PA (n= 11) or secondary amenorrhea (SA n= 20) of unknown etiology, and controls (n= 23), and in Turner syndrome (TS) [45,X (n= 18), mosaicism (n= 7), structural X chromosome abnormalities (SCA, n= 10)], and healthy controls (n= 34). RESULTS: Serum levels of AMH in women with FSHRO were comparable with those in control women (2.76 ± 2.37 versus 3.77 ± 2.36 ng/ml) and significantly higher than in women with PA (0.05 ± 0.04 ng/ml; P < 0.001) or SA of unknown origin (0.12 ± 0.20 ng/ml; P < 0.001). TS girls/women with 45,X or SCA had low serum AMH levels (0.13 ± 0.09 and 0.27 ± 0.19 ng/ml) compared with their controls (3.34 ± 2.23 ng/ml) or subjects with mosaicism (2.33 ± 2.81 ng/ml). AMH expression was detected in granulosa cells of women with FSHRO but not in any of the 45,X fetal ovarian specimens. CONCLUSIONS: A serum AMH assay could be used to identify patients with decreasing ovarian reserves and POI. Moreover, our results support the notion that AMH is secreted mainly by small non-selected follicles, since follicular granulosa cells were AMH-positive and serum AMH levels were normal/low normal in women with FSHRO, who lack follicle development beyond the small antral stage.

Oral, transdermal and vaginal combined contraceptives induce an increase in markers of chronic inflammation and impair insulin sensitivity in young healthy normal-weight women: a randomized study.

STUDY QUESTION: What is the effect of alternative administration routes of combined contraceptives (CCs) on androgen secretion, chronic inflammation, glucose tolerance and lipid profile? SUMMARY ANSWER: The use of oral, transdermal and vaginal CCs impairs glucose tolerance and induces chronic inflammation. WHAT IS KNOWN AND WHAT THIS PAPER ADDS: Oral CCs worsen insulin sensitivity and are associated with increased levels of circulating inflammatory markers, whereas the metabolic effects of transdermal and vaginal CCs have been reported to be minimal. This is the first study comparing three different administration routes of CCs on metabolic variables. STUDY DESIGN, SIZE AND DURATION: This randomized (computer-generated) open-label 9-week follow-up study was conducted at the Oulu University Hospital, Finland. Fasting blood samples were collected at baseline and thereafter at 5 and 9 weeks of treatment, and serum levels of 17-hydroxyprogesterone, androstenedione, testosterone, C-reactive protein (CRP), sex hormone-binding globulin (SHBG), glucose, insulin, C-peptide, total, low-density lipoprotein and high-density lipoprotein cholesterol and triglycerides were measured. Oral glucose tolerance tests were performed and plasma levels of pentraxin 3 (PTX-3) were measured at 0 and 9 weeks. The randomization list, with an allocation ratio of 1:1:1 and block size of six, was computer generated and constructed by a pharmacist at the Oulu University Hospital. The research nurse controlled the randomization list and assigned participants to their groups at the first visit. PARTICIPANTS AND SETTING: Forty-two of 54 healthy women who entered the study used oral contraceptive pills (n = 13), transdermal contraceptive patches (n = 15) or contraceptive vaginal rings (n = 14) continuously for 9 weeks. Inclusion criteria were regular menstrual cycles, at least a 2-month washout as regards hormonal contraceptives and no medication. MAIN RESULTS AND THE ROLE OF CHANCE: Serum levels of SHBG increased and consequently the free androgen index (FAI) decreased in all study groups from baseline to 9 weeks of treatment [FAI, oral: 1.3 (95% confidence interval, CI: 0.94; 1.62) to 0.40 (0.25; 0.54); transdermal: 1.2 (0.96; 1.4) to 0.36 (0.30; 0.43); vaginal: 1.6 (1.1; 2.1) to 0.43 (0.29; 0.58), P < 0.001 in all groups]. Insulin sensitivity was reduced at 9 weeks in all three groups according to the Matsuda index [oral: 7.3 (5.5; 9.0) to 5.6 (3.9; 7.3); transdermal: 9.1 (6.7; 11.4) to 6.6 (4.5; 8.8); vaginal: 7.7 (5.9; 9.5) to 5.4 (3.9; 7.0), P= 0.004-0.024]. Levels of HDL cholesterol, triglycerides and CRP rose in all three groups [CRP, oral: 0.70 (0.38; 1.0) to 5.4 (1.0; 9.9) mg/l; transdermal: 0.77 (0.45; 1.1) to 2.9 (1.4;4.4) mg/l; vaginal: 0.98 (0.52; 1.4) to 3.7 (-0.25; 7.7, a negative value due to skewed distribution to right) mg/l, P≤ 0.002 in all groups] and PTX-3 levels increased in the oral and transdermal study groups (P = 0.007 and P = 0.002). WIDER IMPLICATIONS OF THE FINDINGS: Although the long-term consequences of the present results remain undetermined, these findings emphasize the importance of monitoring glucose metabolism during the use of CCs, especially in women with known risks of type 2 diabetes or cardiovascular diseases. BIAS, LIMITATIONS, GENERALIZABILITY: The number of subjects was relatively low. Moreover, the 9-week exposure to CCs is too short to draw conclusions about the long-term health consequences. However, as the subjects were healthy, normal-weight young women, the possible alterations in the glucose and inflammatory profiles among women with known metabolic risks might be even greater. STUDY FUNDING/COMPETING INTERESTS: This work was supported by grants from the Academy of Finland, the Sigrid Jusélius Foundation, the Finnish Medical Foundation, the Research Foundation of Obstetrics and Gynecology, Oulu University Scholarship Foundation, the North Ostrobothnia Regional Fund of the Finnish Cultural Foundation, the Tyyni Tani Foundation of the University of Oulu and the Finnish-Norwegian Medical Foundation. No competing interests. TRIAL REGISTRATION NUMBER: NCT01087879.

TRAIL pathway components and their putative role in granulosa cell apoptosis in the human ovary.

Extensive apoptotic oocyte reduction occurs during fetal ovarian development. The regulatory pathways responsible for oocyte selection to programmed cell death are, however, poorly understood. The aim of this study was to investigate the potential involvement of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and its death receptors TRAIL-R1/DR4 and TRAIL-R2/DR5 and decoy receptors TRAIL-R3/DcR1 and TRAIL-R4/DcR2 in the apoptotic process characterizing human fetal and adult ovaries. For this purpose, in situ hybridization and immunohistochemistry were applied to human fetal and adult ovarian samples to study the mRNA and protein expression of TRAIL pathway components, and a human granulosa cell tumor-derived cell line (KGN) was used to elucidate functional effects of TRAIL on apoptosis. TRAIL was expressed in human fetal ovary from the 11th week until term. The pro-apoptotic TRAIL-R2/DR5 and the anti-apoptotic TRAIL-R4/DcR2 were also expressed in human ovaries throughout the fetal period. Among the different ovarian cell types, these TRAIL pathway components were mainly localized in the oocytes, and their expression increased towards term. Expression of TRAIL-R1/DR4 and TRAIL-R3/DcR1 was negligible in all of the fetal ovaries studied. Adult ovaries expressed TRAIL, TRAIL-R2/DR5, TRAIL-R3/DcR1 and TRAIL-R4/DcR2 in granulosa cells and oocytes of small primary/secondary follicles as well as in granulosa and theca cells of more developed antral follicles. In KGN cells, TRAIL efficiently induced apoptosis in a dose-dependent manner, and this was blocked by a caspase inhibitor. The results indicate a role of the TRAIL pathway components in the regulation of granulosa cell apoptosis in in vitro and suggest that these factors may have a role in regulating ovarian apoptosis also in vivo.

Effect of mifepristone on the corpus luteum in early pregnancy.

OBJECTIVE: The antiprogestin mifepristone is widely used for medical termination of pregnancy (TOP). Previous studies have suggested that the mechanism of mifepristone is based on its action in the endometrium and myometrium. The aim of this study was to evaluate the possible effects of mifepristone on corpus luteum activity. METHODS: This was a prospective, longitudinal controlled study to which 20 patients undergoing medical TOP (study group) and 20 patients with normal ongoing pregnancy (control group) were recruited. Medical TOP was induced with 200 mg of mifepristone followed by 0.8 mg of misoprostol 2 days later. Three-dimensional ultrasound examinations and hormone assays (progesterone, human chorionic gonadotropin, and 17-hydroxyprogesterone) were performed in both groups on the day of, and 2 days after, administration of mifepristone. Total volume (vascularized + non-vascularized) of the dominant (containing corpus luteum) and non-dominant ovary and serum hormone levels were measured. RESULTS: After administration of mifepristone, a decrease in serum progesterone levels was observed with a simultaneous decrease in the non-vascularized volume of the dominant ovary in the study group. No such changes were observed in the control group. CONCLUSIONS: The observations indicate that, in addition to trophoblastic tissue, the corpus luteum is also the target of mifepristone.

Rosiglitazone treatment increases plasma levels of adiponectin and decreases levels of resistin in overweight women with PCOS: a randomized placebo-controlled study.

OBJECTIVE: Abdominal obesity, insulin resistance and compensatory hyperinsulinaemia play a central role in the pathogenesis of the polycystic ovary syndrome (PCOS). Abdominal adipose tissue is a source of adipokines, such as adiponectin and resistin, both of which may be involved in the development of insulin resistance and chronic inflammation in PCOS. Ghrelin, an important regulatory peptide of food intake, may also play a role in metabolic disturbances related to PCOS. The aim of this study was to examine the effects of 4 months of treatment with the insulin sensitizer rosiglitazone on plasma adiponectin, resistin and ghrelin levels in overweight women with PCOS. DESIGN: A randomised placebo-controlled study. METHODS: Thirty overweight/obese women with PCOS (body mass index>25 kg/m(2), mean age 29.1+/- 1.2 (S.E.M.) years) were randomly allocated to either rosiglitazone (Avandia, 4 mg twice a day) or placebo treatment. Plasma levels of adiponectin, resistin and ghrelin and their correlation to serum levels of insulin, C-peptide and steroid hormones, and insulin sensitivity (euglycaemic hyperinsulinaemic clamp) were assessed. RESULTS: Adiponectin and ghrelin levels correlated significantly with most metabolic markers of insulin resistance and with serum levels of DHEA and 17-hydroxyprogesterone. Plasma levels of adiponectin increased from 9.26+/-0.90 (S.E.M.) to 22.22+/-3.66 microg/ml (P<0.001) and those of resistin decreased from 12.57+/-1.63 to 9.21+/-0.53 ng/ml (P=0.009) at 4 months of treatment, but plasma ghrelin levels did not change. CONCLUSIONS: Rosiglitazone had beneficial effects on serum levels of adiponectin and resistin, suggesting that these adipocytokines may contribute to the improvement in insulin sensitivity observed during the treatment.

Effects of metformin and ethinyl estradiol-cyproterone acetate on lipid levels in obese and non-obese women with polycystic ovary syndrome.

OBJECTIVE: Women with polycystic ovary syndrome (PCOS) exhibit risk factors for cardiovascular diseases such as abdominal obesity, insulin resistance and dyslipidemia. Insulin sensitizers, especially metformin, have been shown to improve these metabolic disturbances, but there are only a few studies on their effects on serum lipids in polycystic ovary syndrome. METHODS: Thirty-five women with PCOS (18 obese and 17 non-obese) were randomized to 6-month treatments with metformin or ethinyl estradiol-cyproterone acetate oral contraceptive pills. RESULTS: In the whole-study population (non-obese and obese women) serum levels of high-density lipoprotein cholesterol increased from 1.4+/-0.2 to 1.6+/-0.1 mmol/l (means +/-S.E. throughout) at 3 and 6 months (P < 0.001), the total cholesterol:high-density lipoprotein cholesterol ratio decreased significantly from 3.8+/-0.3 to 3.3+/-0.2 at 6 months (P < 0.001) and a similar trend was observed in serum triglyceride levels during metformin treatment. In the oral contraceptive group, serum levels of total cholesterol increased from 4.9+/-0.3 to 5.4+/-0.3 mmol/l (P < 0.05), high-density lipoprotein cholesterol increased from 1.2+/-0.1 to 1.5+/-0.1 mmol/l (P < 0.001), the total cholesterol:high-density lipoprotein cholesterol ratio decreased from 4.6+/-0.4 to 3.7+/-0.2 (P < 0.001) and triglycerides increased from 1.3+/-0.1 to 1.9+/-0.2 mmol/l at 6 months of treatment (P < 0.001). Serum low-density lipoprotein cholesterol levels remained unchanged during both treatments. Milder but similar changes in the subgroups of obese and non-obese women were observed during both treatments. Moreover, in the whole-study population both systolic (P = 0.02) and diastolic (P = 0.05) blood pressures decreased over the 6 months of metformin treatment. CONCLUSION: In women with PCOS, metformin treatment had beneficial effects on lipid profile and blood pressure, and therefore it could be useful in the prevention of cardiovascular complications in these women.

Hormonal control of apoptotic cell death in the testis: gonadotropins and androgens as testicular cell survival factors.

Although the requirement for pituitary gonadotropins during testicular cell differentiation is well documented, the possible role of FSH and LH in regulating testicular cell survival has not been studied. Using a quantitative autoradiographic method for the detection of internucleosomal DNA fragmentation, a hallmark feature of apoptosis, the hormonal control of apoptotic cell death was studied in testicular cells collected from immature rats after hypophysectomy. After surgery, animals were treated with daily injections of 20 IU long-acting FSH agonist (FSH-CTP) or 50 IU human CG (hCG) for 2 days. Hypophysectomy decreased testis weight by 25%, but treatment with FSH-CTP or hCG prevented the effect of hypophysectomy. Testes of intact animals contained predominantly high-mol wt DNA, whereas hypophysectomy increased DNA cleavage into low-mol wt (< 15 kilobases) ladders characteristics of apoptosis. In contrast, treatment with FSH-CTP or hCG inhibited hypophysectomy-induced apoptotic DNA cleavage by 84% and 51%, respectively. Hypophysectomy-induced DNA fragmentation was found in both interstitial cells and seminiferous tubules. Similar to whole testis, treatment with FSH-CTP suppressed hypophysectomy-induced apoptosis by over 90% in seminiferous tubules and interstitial cells. In contrast, hCG treatment was less effective in preventing hypophysectomy-induced DNA cleavage (46% suppression in tubules and 77% suppression in interstitial cells). Furthermore, testosterone replacement also suppressed hypophysectomy-induced DNA fragmentation by 75% in the whole testis tissue, 64% in tubules, and 55% in interstitial cells. To further study the role of gonadotropins, intact animals were treated with a potent GnRH antagonist (Azaline B, 10 microgram/day) to decrease serum gonadotropin levels.(ABSTRACT TRUNCATED AT 250 WORDS)

Induction of ovarian follicle luteinization by recombinant follicle-stimulating hormone.

Ovulation and subsequent luteal tissue formation are preceded by midcycle surges of both LH and FSH. Although LH has been widely known as the luteinizing hormone, a potential role for FSH in the luteinization process is possible. Our earlier studies using recombinant FSH (rcFSH) without LH contamination have shown that treatment with a surge dose of rcFSH induces ovulation of mature follicles in hypophysectomized rats. The present studies examined further whether FSH alone is sufficient to induce normal corpus luteum formation. Immature hypophysectomized rats were implanted with an estrogen pellet (10 mg diethylstilbestrol). Two days later, a minipump releasing 4 IU rcFSH/day was placed to induce follicular growth. Forty-eight hours after FSH treatment, both DES pellet and FSH minipump were removed, and rats were injected with a single sc dose of 40 IU rcFSH, 5 micrograms hCG, or saline. For some animals, oviducts were excised the following day to determine the number of ovulated oocytes. The remaining animals received, 2 days later, sc injections of 125 micrograms ovine PRL twice daily for 3 days to maintain luteal function. All rats that received a surge dose of rcFSH or hCG ovulated similar numbers of oocytes, whereas none of the control animals did. Ovaries and blood samples were obtained 5 days after the gonadotropin surge. rcFSH and hCG significantly increased ovarian weight to 73.9 +/- 4.8 and 94.7 +/- 5.6 mg, respectively, compared to 10.0 +/- 0.5 mg in controls. Serum progesterone levels were increased by 192- and 102-fold in rcFSH- and hCG-treated animals, respectively, compared with those in the saline-treated rats. rcFSH and hCG also induced a marked elevation of ovarian [125I]hCG binding (4.2 +/- 0.2 and 3.7 +/- 0.1 ng/mg ovary, respectively), whereas ovaries from control animals exhibited low binding (0.6 +/- 0.1 ng/mg ovary). These gonadotropin-induced increases in [125I]hCG binding were associated with similar elevations in the levels of three LH receptor transcripts of 2.5, 4.2, and 7.0 kilobases. Also, levels of the ovarian cholesterol side-chain cleavage enzyme (CYP 11A) mRNA (2 kilobases) were low in control animals, but increased 20.5- and 14.3-fold after surge doses of rcFSH and hCG, respectively. Accompanied by biochemical signs of luteinization, morphological features typical of luteinized ovaries were found in both rcFSH and hCG groups, showing the formation of large polyhedral lutein cells and small spindle-shaped lutein cells.(ABSTRACT TRUNCATED AT 400 WORDS)