Effect of intrafollicular administration of PGE2 or PGF2α in early estrus on ovulation, hemorrhagic anovulatory follicles formation, progesterone secretion and pregnancy outcome in the mare.

This experiment was performed to evaluate whether intrafollicular treatment of PGE2 or PGF2α administered in early estrus would induce normal ovulation, progesterone production (Experiment 1) and pregnancy (Experiment 2). In Experiment 1, mares in estrus after 2 days of endometrial edema were injected in all largest dominant follicles (28-35 mm in diameter) with 0.5 mL of sterile water containing 500 µg PGE2 (n = 6), 125 µg PGF2α (n = 6) or placebo (n = 7) (Hour 0). Ultrasound examinations were performed daily, until ovulation or anovulation was detected, and daily blood samples were taken for 8 days. In Experiment 2, mares with a dominant follicle ≥35 mm after at least three days of slight-to-moderate endometrial edema, were injected with 500 µg PGE2 diluted in 0.5 mL of sterile water for injection in the follicle (PGE2 group; n = 9 mares and 11 dominant follicles). No puncture was performed in the control group (n = 9 mares and 11 dominant follicles). Mares from both groups were inseminated. In Experiment 1, all mares (6/6) in the PGE2 group ovulated within 24 h of treatment. The mean interval from intrafollicular injection to ovulation was shorter (P < 0.001) in PGE2 mares (24 ± 0 h) than in control mares (77 ± 9 h). Mares from the PGF2α group developed hemorrhagic anovulatory follicles (HAF) more often (7/7) than control mares (2/7); P < 0.05). The progesterone concentration in mares from the PGF2α group was lower (P < 0.004) than control mares in the early post-ovulatory period. The first significant increase in post-ovulatory progesterone concentration occurred earlier (P < 0.05) in mares from the control group than in mares from the PGF2α and PGE2 groups. In Experiment 2, more mares from the control group (7/9, 78 %) became pregnant than from the PGE2 group (2/9, 22 %) (P = 0.015). In conclusion, PGE2 alone induced follicle collapse in all treated mares within 24 h of administrations, while PGF2α blocked ovulation and induced formation of HAFs. However, the post-ovulatory rise in progesterone production was delayed and the fertility reduced in mares with ovulation induced by PGE2 compared to control mares.

Examining the causal relationship between sex hormone-binding globulin (SHBG) and infertility: A Mendelian randomization study.

BACKGROUND: The causal relationship between sex hormone-binding globulin (SHBG) and infertility has remained unclear. Thus, we used Mendelian randomization (MR) to investigate this relationship. METHODS: Risk factors for SHBG were extracted from European individuals within the UK Biobank using single-nucleotide polymorphism (SNP) data. Summary-level data for infertility outcomes were obtained from the FinnGen dataset. The causal relationship between SHBG and infertility was examined using inverse variance weighted, weighted model, weighted median, and MR-Egger regression analyses. Additionally, Cochran's Q test and Egger intercept tests were used to confirm the heterogeneity and pleiotropy of identified instrumental variables (IVs). RESULTS: Our findings revealed a significant negative association between sex hormone-binding globulin (SHBG) levels and infertility, particularly with anovulation, a specific form of female infertility. However, SHBG did not exert a causal impact on male infertility or on female infertility of tubal origin. CONCLUSIONS: SHBG expression offers protection against the development of certain types of female infertility, suggesting it is a potential therapeutic target for infertility.

Resumption of ovulation in anovulatory women with PCOS and obesity is associated with reduction of 11ß-hydroxyandrostenedione concentrations.

STUDY QUESTION: Is resumption of ovulation after a 6-month lifestyle intervention in women with PCOS and obesity associated with differential changes in endocrine and metabolic parameters (weight, insulin resistance, anti-Müllerian hormone (AMH), and androgens) compared to women with PCOS who remained anovulatory? SUMMARY ANSWER: Resumption of ovulation after a 6-month lifestyle intervention in women with PCOS and obesity is associated with changes in serum 11ß-hydroxyandrostenedione (11OHA4) concentrations. WHAT IS KNOWN ALREADY: Lifestyle interventions have been shown to reduce clinical and biochemical hyperandrogenism in women with PCOS. Weight loss of 5-10% may reverse anovulatory status, thereby increasing natural conception rates. However, the mechanisms underlying why some women with PCOS remain anovulatory and others resume ovulation after weight loss are unclear. Reproductive characteristics at baseline and a greater degree of change in endocrine and metabolic features with lifestyle intervention may be crucial for ovulatory response. STUDY DESIGN, SIZE, DURATION: We used data and samples originating from an earlier randomized controlled trial (RCT), which examined the efficacy of a 6-month lifestyle intervention prior to infertility treatment compared to prompt infertility treatment on live birth rate in women with obesity. A total of 577 women with obesity (BMI > 29 kg/m2) were randomized between 2009 and 2012. Anovulatory women with PCOS who were allocated to the intervention arm of the original RCT (n = 95) were included in the current analysis. PARTICIPANTS/MATERIALS, SETTING, METHODS: We defined women as having resumed ovulation (RO+) based on the following criteria: spontaneous pregnancy; or assignment to expectant management; or IUI in natural cycles as the treatment strategy after lifestyle intervention. Steroid hormones were measured using liquid chromatography tandem mass spectrometry. Generalized estimating equations with adjustment for baseline measures and interaction between group and time was used to examine differences in changes of endocrine and metabolic parameters between RO+ (n = 34) and persistently anovulatory women (RO-, n = 61) at 3 and 6 months after intervention. MAIN RESULTS AND THE ROLE OF CHANCE: At baseline, the mean ± SD age was 27.5 ± 3.6 years in the RO+ group and 27.9 ± 4.1 years in the RO- group (P = 0.65), and the mean ± SD weights were 101.2 ± 9.5 kg and 105.0 ± 14.6 kg, respectively (P = 0.13). Baseline AMH concentrations showed significant differences between RO+ and RO- women (median and interquartile range [IQR] 4.7 [3.2; 8.3] versus 7.2 [5.3; 10.8] ng/ml, respectively). Baseline androgen concentrations did not differ between the two groups. During and after lifestyle intervention, both groups showed weight loss; changes in 11OHA4 were significantly different between the RO+ and RO groups (P-value for interaction = 0.03). There was a similar trend for SHBG (interaction P-value = 0.07), and DHEA-S (interaction P-value = 0.06), with the most pronounced differences observed in the first 3 months. Other parameters, such as AMH and FAI, decreased over time but with no difference between the groups. LIMITATIONS, REASONS FOR CAUTION: No high-resolution transvaginal ultrasonography was used to confirm ovulatory status at the end of the lifestyle program. The small sample size may limit the robustness of the results. WIDER IMPLICATIONS OF THE FINDINGS: Reduction of androgen concentrations during and after lifestyle intervention is associated with recovery of ovulatory cycles. If our results are confirmed in other studies, androgen concentrations could be monitored during lifestyle intervention to provide individualized recommendations on the timing of resumption of ovulation in anovulatory women with PCOS and obesity. STUDY FUNDING/COMPETING INTEREST(S): The study was supported by a grant from ZonMw, the Dutch Organization for Health Research and Development (50-50110-96-518). The Department of Obstetrics and Gynecology of the UMCG received an unrestricted educational grant from Ferring Pharmaceuticals BV, The Netherlands. A.H. reports consultancy for the development and implementation of a lifestyle App MyFertiCoach developed by Ferring Pharmaceutical Company. All other authors have no conflicts to declare. TRIAL REGISTRATION NUMBER: The LIFEstyle RCT was registered at the Dutch trial registry (NTR 1530).

A comprehensive review of the new FIGO classification of ovulatory disorders.

BACKGROUND: The World Health Organization (WHO) system for the classification of disorders of ovulation was produced 50 years ago and, by international consensus, has been updated by the International Federation of Gynecology and Obstetrics (FIGO). OBJECTIVE AND RATIONALE: This review outlines in detail each component of the FIGO HyPO-P (hypothalamic, pituitary, ovarian, PCOS) classification with a concise description of each cause, and thereby provides a systematic method for diagnosis and management. SEARCH METHODS: We searched the published articles in the PubMed database in the English-language literature until October 2022, containing the keywords ovulatory disorders; ovulatory dysfunction; anovulation, and each subheading in the FIGO HyPO-P classification. We did not include abstracts or conference proceedings because the data are usually difficult to assess. OUTCOMES: We present the most comprehensive review of all disorders of ovulation, published systematically according to the logical FIGO classification. WIDER IMPLICATIONS: Improving the diagnosis of an individual's ovulatory dysfunction will significantly impact clinical practice by enabling healthcare practitioners to make a precise diagnosis and plan appropriate management.

The melatonin receptor genes are linked and associated with the risk of polycystic ovary syndrome.

Polycystic ovarian syndrome (PCOS) is a genetically complex disorder that involves the interplay of multiple genes and environmental factors. It is characterized by anovulation and irregular menses and is associated with type 2 diabetes. Neuroendocrine pathways and ovarian and adrenal dysfunctions are possibly implicated in the disorder pathogenesis. The melatonin system plays a role in PCOS. Melatonin receptors are expressed on the surface of ovarian granulosa cells, and variations in the melatonin receptor genes have been associated with increased risk of PCOS in both familial and sporadic cases. We have recently reported the association of variants in MTNR1A and MTNR1B genes with familial type 2 diabetes. In this study, we aimed to investigate whether MTNR1A and MTNR1B contribute to PCOS risk in peninsular families. In 212 Italian families phenotyped for PCOS, we amplified by microarray 14 variants in the MTNR1A gene and 6 variants in the MTNR1B gene and tested them for linkage and linkage disequilibrium with PCOS. We detected 4 variants in the MTNR1A gene and 2 variants in the MTNR1B gene significantly linked and/or in linkage disequilibrium with the risk of PCOS (P < 0.05). All variants are novel and have not been reported before with PCOS or any of its related phenotypes, except for 3 variants previously reported by us to confer risk for type 2 diabetes and 1 variant for type 2 diabetes-depression comorbidity. These findings implicate novel melatonin receptor genes' variants in the risk of PCOS with potential functional roles.

Polycystic ovary syndrome and adverse pregnancy outcomes: potential role of decidual function.

Polycystic ovary syndrome (PCOS) is a common endocrine disorder affecting fertility and mental health among women of reproductive age. In addition to anovulation and hyperandrogenism, patients also experience metabolic issues, such as insulin resistance, obesity, and dyslipidemia, as well as chronic low-grade inflammation throughout the body. Recent studies have shown that even with assisted reproductive technology to treat anovulatory issues, patients with PCOS still have higher rates of adverse pregnancy outcomes and abortion compared to normal pregnancies. These findings suggest that PCOS may impair the endometrium and disrupt the onset and maintenance of healthy pregnancies. Decidualization is a crucial step in the process of healthy pregnancy, during which endometrial stromal cells (ESCs) differentiate into secretory decidual stromal cells (DSCs) regulated by hormones and local metabolism. This article comprehensively reviews the pathological processes of PCOS and the mechanisms involved in its impaired decidualization. In addition, we explore how PCOS increases the incidence of adverse pregnancy outcomes (APO). By gaining a better understanding of the adverse effects of PCOS on pregnancy and its specific mechanisms, we hope to provide a theoretical basis for reducing APO and improving the live birth rate among women with PCOS.

Does bisphenol A (BPA) participates in the pathogenesis of Polycystic Ovary Syndrome (PCOS)?

PCOS is an endocrine disorder characterized by chronic anovulation, hyperandrogenism, and polycystic ovaries. Its etiology is uncertain. It is debated whether BPA would be a component of the environmental factor in the etiology of PCOS. Contamination by BPA can occur from food packaging (exposure during the diet) and through skin absorption and/or inhalation. It can be transferred to the fetus via the placenta or to the infant via breast milk, and it can be found in follicular fluid, fetal serum, and amniotic fluid. The phenolic structure of BPA allows it to interact with Estrogen Receptors (ERs) through genomic signaling, in which BPA binds to nuclear ERα or Erß, or through nongenomic signaling by binding to membrane ERs, prompting a rapid and intense response. With daily and constant exposure, BPA's tendency to bioaccumulate and its ability to activate nongenomic signaling pathways can alter women's metabolic and reproductive function, leading to hyperandrogenism, insulin resistance, obesity, atherogenic dyslipidemia, chronic inflammatory state, and anovulation and favoring PCOS. The harmful changes caused by BPA can be passed on to future generations without the need for additional exposure because of epigenetic modifications. Not only high BPA levels can produce harmful effects, but at low levels, BPA may be harmful when exposure occurs during the most vulnerable periods, such as the fetal and neonatal periods, as well as during the prepubertal age causing an early accumulation of BPA in the body. Learning how BPA participates in the pathogenesis of PCOS poses a challenge and further studies should be conducted.

A review of nitric oxide and oxidative stress in typical ovulatory women and in the pathogenesis of ovulatory dysfunction in PCOS.

Polycystic ovary syndrome (PCOS) is a heterogeneous functional endocrine disorder associated with a low-grade, chronic inflammatory state. Patients with PCOS present an increased risk of metabolic comorbidities and often menstrual dysregulation and infertility due to anovulation and/or poor oocyte quality. Multiple mechanisms including oxidative stress and low-grade inflammation are believed to be responsible for oocyte deterioration; however, the influence of nitric oxide (NO) insufficiency in oocyte quality and ovulatory dysfunction in PCOS is still a matter for debate. Higher production of superoxide (O2•-) mediated DNA damage and impaired antioxidant defense have been implicated as contributory factors for the development of PCOS, with reported alteration in superoxide dismutase (SOD) function, an imbalanced zinc/copper ratio, and increased catalase activity. These events may result in decreased hydrogen peroxide (H2O2) accumulation with increased lipid peroxidation events. A decrease in NO, potentially due to increased activity of NO synthase (NOS) inhibitors such as asymmetric dimethylarginine (ADMA), and imbalance in the distribution of reactive oxygen species (ROS), such as decreased H2O2 and increased O2•-, may offset the physiological processes surrounding follicular development, oocyte maturation, and ovulation contributing to the reproductive dysfunction in patients with PCOS. Thus, this proposal aims to evaluate the specific roles of NO, oxidative stress, ROS, and enzymatic and nonenzymatic elements in the pathogenesis of PCOS ovarian dysfunction, including oligo- anovulation and oocyte quality, with the intent to inspire better application of therapeutic options. The authors believe more consideration into the specific roles of oxidative stress, ROS, and enzymatic and nonenzymatic elements may allow for a more thorough understanding of PCOS. Future efforts elaborating on the role of NO in the preoptic nucleus to determine its influence on GnRH firing and follicle-stimulating hormone/Luteinizing hormone (FSH/LH) production with ovulation would be of benefit in PCOS. Consequently, treatment with an ADMA inhibitor or NO donor may prove beneficial to PCOS patients experiencing reproductive dysfunction and infertility.

Letrozole in fertility treatment.

This review describes the current evidence regarding the putative indications of letrozole (LTZ) in fertility treatment. Prior to intrauterine insemination, LTZ is recommended in women with normogonadotrophic oligo-anovulation. In ovulatory women, LTZ is equal to clomiphene and may be used instead of exogenous gonadotrophin. LTZ may be used as co-treatment in poor responders prior to in vitro fertilization/intracytoplasmic sperm injection. In addition, LTZ prior to frozen-thawed embryo transfer is increasingly used in women with normogonadotrophic oligo-anovulation.

The effect of laparoscopic ovarian drilling in patients with anovulatory polycystic ovary syndrome and high serum levels of anti-Müllerian hormone.

Female infertility is often associated with anovulatory polycystic ovary syndrome (PCOS), characterized by high serum levels of anti-Müllerian hormone (AMH). Laparoscopic ovarian drilling (LOD) is commonly used to treat PCOS, especially when drug interventions have failed. This study aimed to evaluate the response to LOD intervention in women with PCOS by assessing AMH serum levels and their ability to restore normal physiological menstrual cycle and achieve conception. Seventy-five infertile women (24-41 years old) with body mass index (BMI) ranging from 19.6-35kg/m2 were included in the study. Among them, 57 had primary infertility, and 18 from secondary infertility, with an average duration of 8.6±4.4 years. Baseline levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), and AMH were measured, and post-LOD levels of LH and AMH were evaluated. Menstrual cycle regularity was evaluated before and after LOD. Baseline FSH serum level before LOD was 5.2-1.6IU/L. Following LOD, the serum levels of LH and AMH significantly decreased from 14.3±4.1 to 7.8±2.8 IU/L and from 13.7±5.9 to 7.7±3.9 IU/L, respectively (p<0.05). LOD significantly (p<0.05) decreased the menstrual cycles irregularity, such as oligomenorrhea and amenorrhea, from 55 (73.3%) to 22 (29.3%) women and from 2 (2.7%) to 0 (0%) women respectively. Moreover, regular menstrual cycles significantly (p<0.05) increased from 18 (24%) to 53 (70.7%) women. Importantly, 68% of LOD-treated women showed a significant increase in pregnancy rates, with 52.9%, 35.3%, and 11.8% achieving pregnancy within 3, 6, and 9 months after LOD, respectively (p<0.05). Moreover, spontaneous ovulation was observed in 7/75 (9.3%) women within 90 days after LOD, and 71.4% achieved pregnancy. These findings highlight the success of laparoscopic ovarian drilling as an intervention for PCOS, with AMH serving as a reliable test to assess the response to LOD treatment.

Opportunities and challenges: interleukin-22 comprehensively regulates polycystic ovary syndrome from metabolic and immune aspects.

Polycystic ovary syndrome (PCOS) is known as a prevalent but complicated gynecologic disease throughout the reproductive period. Typically, it is characterized by phenotypic manifestations of hyperandrogenism, polycystic ovary morphology, and persistent anovulation. For now, the therapeutic modality of PCOS is still a formidable challenge. Metabolic aberrations and immune challenge of chronic low-grade inflammatory state are significant in PCOS individuals. Recently, interleukin-22 (IL-22) has been shown to be therapeutically effective in immunological dysfunction and metabolic diseases, which suggests a role in the treatment of PCOS. In this review, we outline the potential mechanisms and limitations of IL-22 therapy in PCOS-related metabolic disorders including its regulation of insulin resistance, gut barrier, systemic inflammation, and hepatic steatosis to generate insights into developing novel strategies in clinical practice.

Hyperandrogenism.

Hyperandrogenism is a common condition encountered by pediatric and adolescent physicians. Most girls with hyperandrogenism represent physiological pubertal variation; pathology may be present in a substantial minority. Systematic evaluation is essential to avoid unnecessary work-up in physiological causes while not missing pathological causes. Polycystic ovarian syndrome (PCOS), unexplained, persistent hyperandrogenism of ovarian origin, is the most common form in adolescent girls. The high prevalence of physiological peripubertal hirsutism, anovulation, and polycystic ovarian morphology results in mislabeling many girls as having the polycystic ovarian syndrome, a disorder with lifelong implications. The use of strict criteria of age-specific anovulation, hyperandrogenism, and duration is essential to reduce their stigmatization. The exclusion of secondary causes by screening tests (cortisol, thyroid profile, prolactin, and 17OHP) is essential before undertaking treatment for PCOS. Lifestyle measures, estrogen-progesterone preparations, antiandrogens, and metformin are the cornerstone of managing the disorder.

Effect of repeated low doses of GnRH analogue (buserelin) on fertility performance of dairy cows with anovulation type I.

The aim of this study was to evaluate the fertility response of dairy cows with anovulation type I on repeated low doses of GnRH agonist buserelin. The study was conducted on 83 anovulatory and 60 cyclic Polish Holstein Friesian cows. Anovulation type I was defined as small ovaries with follicles of ≤ 5 mm in diameter and without corpus luteum on two examinations in a 7-10 day interval between 50-60 days after parturition. Cows from the experimental group (n=58) received 0.4 µg of buserelin i.m. once a day for 5 consecutive days. Cows from the negative control group (n = 25) received saline. Sixty cyclic cows receiving no treatment served as positive controls. Intervals from calving to estrus and from calving to conception, pregnancy rate 30-35 days and 260 days after AI, and pregnancy loss were calculated. The anovulatory cows had a substantially prolonged calving to conception interval, decreased pregnancy rate and increased pregnancy loss and culling rate compared to cyclic herd mates. The average calving to conception interval was significantly (p⟨0.05) shorter in treated cows compared to non-treated anovulatory cows (153.7 days vs 209.3 days). In conclusion, repeated low doses of GnRH analogue buserelin led to a significant shortening of calving to conception interval. More clinical trials are needed to determine the practical usefulness of this method for the treatment of anovulation type I in dairy cows.

The Prevalence of Menstrual Cycle Disorders and Menstrual Cycle-Related Symptoms in Female Athletes: A Systematic Literature Review.

BACKGROUND: Menstrual cycle (MC) disorders and MC-related symptoms can have debilitating effects on the health and performance of female athletes. As the participation of women in sports continues to increase, understanding the prevalence of a range of MC disorders and MC-related symptoms may guide preventive strategies to protect the health and optimise the performance of female athletes. OBJECTIVE: To examine the prevalence of MC disorders and MC-related symptoms among female athletes who are not using hormonal contraceptives and evaluate the assessment methods used to identify MC disorders and MC-related symptoms. METHODS: This systematic review was performed in accordance with the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA). Six databases were searched until September 2022 for all original research that reported the prevalence of MC disorders and/or MC-related symptoms in athletes not using hormonal contraceptives, which included the definitions of the MC disorders examined, and the assessment methods used. MC disorders included amenorrhoea, anovulation, dysmenorrhoea, heavy menstrual bleeding (HMB), luteal phase deficiency (LPD), oligomenorrhoea, premenstrual syndrome (PMS) and premenstrual dysphoric disorder (PMDD). MC-related symptoms included any affective and physical symptoms related to the MC that do not cause significant personal, interpersonal or functional impairment. The prevalence data across eligible studies were combined, and all studies were qualitatively synthesised to evaluate the assessment methods and tools used to identify MC disorders and MC-related symptoms. The methodological quality of studies was assessed using a modified Downs and Black checklist. RESULTS: Sixty studies involving 6380 athletes were included. A wide range of prevalence was observed for all types of MC disorders, with a dearth of data on anovulation and LPD. Based on pooled data, dysmenorrhoea (32.3%; range 7.8-85.6%) was the most prevalent MC disorder. Studies reporting MC-related symptoms mostly examined the premenstrual and menstruation phases, where affective symptoms appeared more prevalent than physical symptoms. A larger proportion of athletes reported symptoms during the initial days of menstruation compared with the premenstrual phase. MC disorders and MC-related symptoms were retrospectively assessed using self-report methods in 90.0% of studies. Most studies (76.7%) in this review were graded as moderate quality. DISCUSSION: MC disorders and MC-related symptoms are commonplace among female athletes, warranting further research examining their impact on performance and preventive/management strategies to optimise athlete health. To increase the quality of future studies, researchers should adopt standardised definitions of MC disorders and assessment methods such as a combination of calendar counting, urinary ovulation tests and a mid-luteal phase serum progesterone measurement when assessing menstrual function. Similarly, standardised diagnostic criteria should be used when examining MC disorders such as HMB, PMS and PMDD. Practically, implementing prospective cycle monitoring that includes ovulation testing, mid-luteal blood sampling (where feasible) and symptom logging throughout the MC could support athletes and practitioners to promptly identify and manage MC disorders and/or MC-related symptoms. TRIAL REGISTRATION: This review has been registered in the PROSPERO database (CRD42021268757).

In praise of ovulation induction for the management of anovulatory subfertility.

Rapid advances in assisted reproductive technology have revolutionized fertility treatments for couples worldwide seeking a pregnancy. Although this is promising, concerns are emerging over the overuse of unnecessary assisted conception treatments, particularly among couples with anovulatory subfertility. Some experts are calling for the cessation of ovulation induction as the primary treatment of anovulatory subfertility in favour of more sophisticated assisted conception treatments. In the absence of other causes of subfertility, ovulation induction in patients with type 1 and type 2 anovulation disorders can achieve an up to 80% ovulation rate with a 40% cumulative pregnancy rate and few adverse effects. Considering the various risks and high costs associated with assisted reproductive technology treatments, it is hard to argue for their cost-effectiveness when simpler, safer and cheaper pharmacological ovulation induction could achieve comparable pregnancy rates. We argue here for the safe, effective and ethical use of ovulation induction in this population, supplemented by a judicious use of assisted conception treatments. We emphasize the essential role of ovulation induction as a first-line intervention for couples with anovulatory subfertility delivered within a patient-centred multidisciplinary care model and with a clear escalation pathway to use assisted reproductive technology treatments based on the person's response, characteristics and treatment preference.

Immune Dysfunction in Polycystic Ovary Syndrome.

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in reproductive-aged individuals with ovaries. It is associated with anovulation and increased risk to fertility and metabolic, cardiovascular, and psychological health. The pathophysiology of PCOS is still inadequately understood, although there is evidence of persistent low-grade inflammation, which correlates with associated visceral obesity. Elevated proinflammatory cytokine markers and altered immune cells have been reported in PCOS and raise the possibility that immune factors contribute to ovulatory dysfunction. Because normal ovulation is modulated by immune cells and cytokines in the ovarian microenvironment, the endocrine and metabolic abnormalities associated with PCOS orchestrate the accompanying adverse effects on ovulation and implantation. This review evaluates the current literature on the relationship between PCOS and immune abnormalities, with a focus on emerging research in the field.

The future of frozen-thawed embryo transfer in hormone replacement therapy cycles.

PURPOSE OF REVIEW: This review focuses on the efficacy of letrozole stimulated frozen-thawed embryo transfer (FET) compared to hormone replacement therapy (HRT) FET in women with polycystic ovarian syndrome (PCOS) and/or oligo-anovulation. Further, obstetric and perinatal risks in HRT FET are summarized. RECENT FINDINGS: The presence of a corpus luteum seems to reduce the risk of pregnancy-related hypertension and preeclampsia after FET. As a natural cycle (NC) FET is not an option for women with oligo-/amenorrhea these women may benefit from FET with mild stimulation compared to HRT FET. The intention of mild stimulation in anovulatory women is to induce (mono) ovulation to mimic the endocrine profiles of the natural cycle and the early pregnancy after natural conception. Mild stimulation by letrozole is patient friendly and cheap compared to gonadotropin stimulated FET and has been increasingly used in recent years. Although the quality of evidence is low, the pregnancy outcomes after letrozole FET seems similar or even better compared to HRT FET in women with PCOS and/or oligo-anovulation. SUMMARY: Natural and modified NC FET should be used whenever possible to mitigate adverse obstetric and perinatal outcomes after HRT FET. For anovulatory women, whenever ovulation can be induced, we advocate the use of mild stimulation FET to create a corpus luteum awaiting results from RCTs limited to oligo-anovulatory women.

Toward an optimal contraception dosing strategy.

Anovulation refers to a menstrual cycle characterized by the absence of ovulation. Exogenous hormones such as synthetic progesterone and estrogen have been used to attain this state to achieve contraception. However, large doses are associated with adverse effects such as increased risk for thrombosis and myocardial infarction. This study utilizes optimal control theory on a modified menstrual cycle model to determine the minimum total exogenous estrogen/progesterone dose, and timing of administration to induce anovulation. The mathematical model correctly predicts the mean daily levels of pituitary hormones LH and FSH, and ovarian hormones E2, P4, and Inh throughout a normal menstrual cycle and reflects the reduction in these hormone levels caused by exogenous estrogen and/or progesterone. Results show that it is possible to reduce the total dose by 92% in estrogen monotherapy, 43% in progesterone monotherapy, and that it is most effective to deliver the estrogen contraceptive in the mid follicular phase. Finally, we show that by combining estrogen and progesterone the dose can be lowered even more. These results may give clinicians insights into optimal formulations and schedule of therapy that can suppress ovulation.

Effects of intestinal flora on polycystic ovary syndrome.

Polycystic ovary syndrome (PCOS) is a common endocrine disorder in women of reproductive age. Its clinical characteristics are mainly oligo-ovulation or anovulation, hyperandrogenemia (HA) and insulin resistance (IR). PCOS is considered to be one of the main causes of infertility in women of childbearing age, and its pathogenesis is still unclear. Intestinal flora, known as the "second genome" of human beings, is closely related to metabolic diseases, immune diseases and infectious diseases. At the same time, mounting evidence suggests that intestinal flora can regulate insulin synthesis and secretion, affect androgen metabolism and follicular development, and is involved in the occurrence of chronic inflammation and obesity. The imbalance of intestinal flora is caused by the abnormal interaction between intestinal flora and host cells caused by the change of intestinal microbial diversity, which is related to the occurrence and development of PCOS. The adjustment of intestinal flora may be a potential direction for the treatment of PCOS.

Deletion of Androgen Receptor in LepRb Cells Improves Estrous Cycles in Prenatally Androgenized Mice.

Androgens are steroid hormones crucial for sexual differentiation of the brain and reproductive function. In excess, however, androgens may decrease fertility as observed in polycystic ovary syndrome, a common endocrine disorder characterized by oligo/anovulation and/or polycystic ovaries. Hyperandrogenism may also disrupt energy homeostasis, inducing higher central adiposity, insulin resistance, and glucose intolerance, which may exacerbate reproductive dysfunction. Androgens bind to androgen receptors (ARs), which are expressed in many reproductive and metabolic tissues, including brain sites that regulate the hypothalamo-pituitary-gonadal axis and energy homeostasis. The neuronal populations affected by androgen excess, however, have not been defined. We and others have shown that, in mice, AR is highly expressed in leptin receptor (LepRb) neurons, particularly in the arcuate (ARH) and the ventral premammillary nuclei (PMv). Here, we assessed if LepRb neurons, which are critical in the central regulation of energy homeostasis and exert permissive actions on puberty and fertility, have a role in the pathogenesis of female hyperandrogenism. Prenatally androgenized (PNA) mice lacking AR in LepRb cells (LepRbΔAR) show no changes in body mass, body composition, glucose homeostasis, or sexual maturation. They do show, however, a remarkable improvement of estrous cycles combined with normalization of ovary morphology compared to PNA controls. Our findings indicate that the prenatal androgenization effects on adult reproductive physiology (ie, anestrus and anovulation) are mediated by a subpopulation of LepRb neurons directly sensitive to androgens. They also suggest that the effects of hyperandrogenism on sexual maturation and reproductive function in adult females are controlled by distinct neural circuits.