Serum erythropoietin level is increased during stimulation for IVF but not in OHSS.

BACKGROUND: Erythropoietin (Epo) is a potent vascular growth factor that induces angiogenesis and antiapoptotic signalling. We investigated whether the development of numerous follicles and corpora lutea during in vitro fertilization (IVF) cycle affects circulating Epo levels and further, if Epo could be used as a novel marker for ovarian hyperstimulation syndrome (OHSS). METHODS: 24 women were included in the uncomplicated IVF group and 35 women in the OHSS group. Repeated blood samples from both groups were analysed for Epo, progesterone, blood haemoglobin, and creatinine. Follicular fluid from the IVF group was analysed for Epo and progesterone. Repeated measure analysis was performed for the variables and circulating Epo levels were compared between the IVF group and early OHSS. Furthermore, related growth factors, vascular endothelial growth factor (VEGF) and hypoxia-inducible factor-1 (HIF-1) were analysed from subgroup of women to test for correlation with Epo. RESULTS: During IVF, circulating Epo increased from natural mid-luteal phase to stimulated mid-luteal phase (median 9.5; 95% CI 7.2-13.4 IU/L and 12.5; 10.3-13.4 IU/L; p = 0.003). In cycles resulting in pregnancy, Epo level decreased 14 days after oocyte pick-up (OPU) and remained low thereafter. In cycles not resulting in pregnancy, Epo level increased again 35 days after OPU. Follicle fluid Epo concentration was 1.5 times higher than the serum concentration (median 15.4; 95% CI 10.4-19.2 IU/L vs. 10.2; 8.8-12.7; p = 0.006). There was no difference in circulating Epo concentration between early OHSS and uncomplicated IVF. Circulating Epo did not correlate with VEGF or HIF-1. CONCLUSIONS: Circulating Epo levels fluctuate during IVF cycle. We hypothesise this may suggest Epo's involvement in ovarian physiology and angiogenesis. However, Epo was not a clinical marker for OHSS.

Risk of ovarian cancer in women who give birth after assisted reproductive technology (ART)-a registry-based Nordic cohort study with follow-up from first pregnancy.

BACKGROUND: There is concern that assisted reproductive technology (ART) may increase ovarian cancer risk, but previous studies are inconclusive. We compared ovarian cancer risk for women who gave birth after ART vs natural conception. METHODS: Through linkage of nationwide registry data, we followed 3,303,880 initially nulliparous women in Denmark (1994-2014), Finland (1990-2014), Norway (1984-2015) and Sweden (1985-2015) from first pregnancy ≥22 weeks to ovarian cancer, emigration, death or end of follow-up (2014/2015). We estimated hazard ratios (HRs), adjusting for age, parity, maternal birth year and country, and for body mass index and smoking in subsamples. RESULTS: Mean age at first birth was 27.7 years. During a mean follow-up of 14.4 person-years, 2683 participants (0.08%) developed ovarian cancer; 135 after ART and 2548 after natural conception only (incidence rates 11.6 and 5.5 per 100,000 person-years, respectively). The risk was higher for women who ever gave birth after ART (HR 1.70, 95% confidence interval 1.42-2.03) compared to natural conception. Associations were stronger for conventional in vitro fertilisation than for intracytoplasmic sperm injection. CONCLUSIONS: Among parous women, ART-conception was associated with a higher risk of ovarian cancer than natural conception. Further studies should decipher whether this is causal or confounded by infertility or other factors.

Effects of letrozole on serum estradiol and estrone in postmenopausal breast cancer patients and tolerability of treatment: a prospective trial using a highly sensitive LC-MS/MS (liquid chromatography-tandem mass spectrometry) method for estrogen measurement.

PURPOSE: To analyze serum estradiol (E2) and estrone (E1) during letrozole treatment and their association to Quality of Life (QoL) and side-effects. METHODS: Postmenopausal breast cancer patients starting adjuvant letrozole were eligible. Serum samples were taken at baseline, three, and 12 months. E2 and FSH were measured with routine chemiluminescent immunoassays. E2 and E1 were analyzed after trial completion with a highly sensitive liquid chromatography-tandem mass spectrometry method (LC-MS/MS) with lower limits of quantification (LLOQ) of 5 pmol/L. QoL was measured at baseline and at 12 months with the EORTC QLQ-C30 and QLQ-BR23 and the Women's Health questionnaires, and menopause-related symptoms with the modified Kupperman Index. RESULTS: Of 100 screened patients 90 completed the trial. Baseline mean LC-MS/MS E2 and E1 were 12 pmol/L (range < 5-57) and 66 pmol/L (< 5-226), respectively. E2 levels measured by immunoassay and LC-MS/MS showed no correlation. E2 and E1 were completely suppressed by letrozole except for one occasion (E1 11 pmol/L at 3 months). Pain, side effects of systemic therapy, vasomotor symptoms, joint and muscle aches, and vaginal dryness increased during letrozole treatment. A high baseline E2 was significantly associated with increased aching joints and muscles, but not with the other side effects. CONCLUSIONS: Letrozole supresses E2 and E1 completely below the LLOQ of the LC-MS/MS in postmenopausal women. High pre-treatment E2 levels were associated with more joint and muscle pain during letrozole. Automated immunoassays are unsuitable for E2 monitoring during letrozole therapy due to poor sensitivity.

Cancer in children born after frozen-thawed embryo transfer: A cohort study.

BACKGROUND: The aim was to investigate whether children born after assisted reproduction technology (ART), particularly after frozen-thawed embryo transfer (FET), are at higher risk of childhood cancer than children born after fresh embryo transfer and spontaneous conception. METHODS AND FINDINGS: We performed a registry-based cohort study using data from the 4 Nordic countries: Denmark, Finland, Norway, and Sweden. The study included 7,944,248 children, out of whom 171,774 children were born after use of ART (2.2%) and 7,772,474 children were born after spontaneous conception, representing all children born between the years 1994 to 2014 in Denmark, 1990 to 2014 in Finland, 1984 to 2015 in Norway, and 1985 to 2015 in Sweden. Rates for any cancer and specific cancer groups in children born after each conception method were determined by cross-linking national ART registry data with national cancer and health data registries and population registries. We used Cox proportional hazards models to estimate the risk of any cancer, with age as the time scale. After a mean follow-up of 9.9 and 12.5 years, the incidence rate (IR) of cancer before age 18 years was 19.3/100,000 person-years for children born after ART (329 cases) and 16.7/100,000 person-years for children born after spontaneous conception (16,184 cases). Adjusted hazard ratio (aHR) was 1.08, 95% confidence interval (CI) 0.96 to 1.21, p = 0.18. Adjustment was performed for sex, plurality, year of birth, country of birth, maternal age at birth, and parity. Children born after FET had a higher risk of cancer (48 cases; IR 30.1/100,000 person-years) compared to both fresh embryo transfer (IR 18.8/100,000 person-years), aHR 1.59, 95% CI 1.15 to 2.20, p = 0.005, and spontaneous conception, aHR 1.65, 95% CI 1.24 to 2.19, p = 0.001. Adjustment either for macrosomia, birth weight, or major birth defects attenuated the association marginally. Higher risks of epithelial tumors and melanoma after any assisted reproductive method and of leukemia after FET were observed. The main limitation of this study is the small number of children with cancer in the FET group. CONCLUSIONS: Children born after FET had a higher risk of childhood cancer than children born after fresh embryo transfer and spontaneous conception. The results should be interpreted cautiously based on the small number of children with cancer, but the findings raise concerns considering the increasing use of FET, in particular freeze-all strategies without clear medical indications. TRIAL REGISTRATION: Trial registration number: ISRCTN 11780826.

Female reproductive tract microbiota and recurrent pregnancy loss: a nested case-control study.

RESEARCH QUESTION: Is the composition of the endometrial or vaginal microbiota associated with recurrent pregnancy loss (RPL)? DESIGN: Endometrial and vaginal samples were collected from 47 women with two or more consecutive pregnancy losses and 39 healthy control women without a history of pregnancy loss, between March 2018 and December 2020 at Helsinki University Hospital, Helsinki, Finland. The compositions of the endometrial and vaginal microbiota, analysed using 16S rRNA gene amplicon sequencing, were compared between the RPL and control women, and between individual vaginal and endometrial samples. The mycobiota composition was analysed using internal transcribed spacer 1 amplicon sequencing for a descriptive summary. The models were adjusted for body mass index, age and parity. False discovery rate-corrected P-values (q-values) were used to define nominal statistical significance at q < 0.05. RESULTS: Lactobacillus crispatus was less abundant in the endometrial samples of women with RPL compared with controls (mean relative abundance 17.2% versus 45.6%, q = 0.04). Gardnerella vaginalis was more abundant in the RPL group than in controls in both endometrial (12.4% versus 5.8%, q < 0.001) and vaginal (8.7% versus 5.7%, q = 0.002) samples. The individual vaginal and endometrial microbial compositions correlated strongly (R = 0.85, P < 0.001). Fungi were detected in 22% of the endometrial and 36% of the vaginal samples. CONCLUSIONS: Dysbiosis of the reproductive tract microbiota is associated with RPL and may represent a novel risk factor for pregnancy losses.

The effect of paternal and maternal factors on the prognosis of live birth in couples with recurrent pregnancy loss.

INTRODUCTION: Currently, recurrent pregnancy loss (RPL) examinations focus on the woman, although paternal factors are also involved. Men in couples with RPL have higher sperm DNA fragmentation levels than fertile men, but the effect of sperm DNA damage on couple's later prognosis is unknown. Advanced maternal age and obesity are associated with RPL, but paternal lifestyle factors are less studied. Therefore, we aimed to study the associations of couples' lifestyle factors, causes of RPL, and sperm DNA fragmentation with their prognosis of future live birth. MATERIAL AND METHODS: This descriptive cohort study comprised 506 couples investigated for RPL at Helsinki University Hospital, Finland, between 2007 and 2016, linked with national health and population registers. The primary outcome was couple's live birth after RPL investigations. Data on couple's background factors, including age, body mass index, smoking, and alcohol use, were collected from medical records. Sperm DNA fragmentation index was analyzed from 211 men using the sperm chromatin dispersion test. The associations between background factors, sperm DNA fragmentation, and cumulative probability of live birth over time were analyzed using cross-tabulations and age-adjusted Cox regression. RESULTS: In all, 352 of 506 couples (69.6%) achieved live birth. Maternal age, unexplained RPL, prolonged pregnancy attempts before investigations, paternal obesity, and maternal smoking were associated with prognosis: unadjusted hazard ratio for couple's live birth for women aged 35-39 vs younger than 30 years was 0.63 (95% confidence interval [CI] 0.47-0.84), and for 40 years or older was 0.36 (95% CI 0.22-0.58). Age-adjusted hazard ratio for unexplained vs explained RPL was 1.39 (95% CI 1.12-1.72), for couple's pregnancy attempt at least 4 years vs less than 2 years was 0.50 (95% CI 0.33-0.76), for paternal body mass index at least 30 kg/m2 vs less than 25 kg/m2 was 0.67 (95% CI 0.46-0.98), and for maternal smoking was 0.71 (95% CI 0.51-0.99). Altogether, 96/135 (71.1%) couples with normal (<15%), 38/60 (63.3%) with intermediate (15-30%), and 11/16 (68.8%) with high sperm DNA fragmentation index achieved live birth (p = 0.56). CONCLUSIONS: In couples with RPL, prolonged pregnancy attempts, a cause found in RPL examinations, lifestyle factors, and maternal age are negatively associated with their prognosis of future live birth. Sperm DNA fragmentation was not associated, but the number of men with damaged spermatozoa was small. We suggest that clinicians include women and men in RPL counseling because couple's joint lifestyle seems to determine their later prognosis.

Top-quality embryo transfer is associated with lower odds of ectopic pregnancy.

INTRODUCTION: The incidence of ectopic pregnancy is up to four times higher after in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) than in spontaneous pregnancies, and the risk of ectopic pregnancy is increased by tubal factor infertility and the transfer of multiple embryos. However, the effect of embryo quality on the probability of ectopic pregnancy has not been investigated until now and it is not clear whether ovarian stimulation parameters affect the incidence of ectopic pregnancy. MATERIAL AND METHODS: An historical cohort study of 15 006 clinical pregnancies (diagnosed by ultrasound at 6-8 gestational weeks) after non-donor IVF/ICSI with fresh embryo transfer (n = 8952) or frozen-thawed embryo transfer (n = 6054). Treatments were performed during 2000-2017 in Finland. A total of 9207 (61.4%) single and 5799 (38.6%) double embryo transfers of no more than one top-quality embryo were evaluated. We analyzed the effects of multiple factors on ectopic pregnancy by logistic regression, including type of cycle (fresh vs frozen embryo transfer), female age, number and quality of embryos transferred, tubal factor infertility and factors of ovarian response to gonadotropin stimulation. RESULTS: Ectopic pregnancy was observed in 2.3% of cycles. There was no significant difference in ectopic pregnancy rate after fresh embryo transfer and frozen embryo transfer (2.2% vs 2.4%, p = 0.3). The ectopic pregnancy rate was lower in cycles with top-quality embryo transfer (1.9%) than of those where only non-top quality embryos were transferred (2.7%, p < 0.0001). Tubal factor infertility was diagnosed more often in ectopic pregnancy than in intrauterine pregnancies (21.2% vs 11.0%, p < 0.0001). Logistic regression revealed lower odds for ectopic pregnancy after a top-quality embryo transfer than after transfer of a non-top quality embryo (odds ratio [OR] 0.72, 95% confidence interval [CI] 0.56-0.92, p = 0.007). Transfer of two vs one embryo (OR 1.35, 95% CI 1.05-1.70, p = 0.02) and tubal factor infertility (OR 2.21, 95% CI 1.68-2.91, p < 0.0001) significantly increased the risk of ectopic pregnancy. CONCLUSIONS: Transfer of non-top quality embryos is associated with a higher rate of ectopic pregnancy. This is particularly important to keep in mind in treatments with only non-top embryos available even in the absence of tubal factor infertility. To minimize the risk of ectopic pregnancy, the number of embryos transferred should be as low as possible.

Separating parental and treatment contributions to perinatal health after fresh and frozen embryo transfer in assisted reproduction: A cohort study with within-sibship analysis.

BACKGROUND: Compared to naturally conceived children, adverse perinatal outcomes are more common among children born after assisted reproductive technology with fresh embryo transfer (fresh-ET) or frozen embryo transfer (frozen-ET). However, most previous studies could not adequately control for family confounding factors such as subfertility. We compared birth size and duration of pregnancy among infants born after fresh-ET or frozen-ET versus natural conception, using a within-sibship design to account for confounding by maternal factors. METHODS AND FINDINGS: This registry-based cohort study with nationwide data from Denmark (1994-2014), Norway (1988-2015), and Sweden (1988-2015) consisted of 4,510,790 live-born singletons, 4,414,703 from natural conception, 78,095 from fresh-ET, and 17,990 from frozen-ET. We identified 33,056 offspring sibling groups with the same mother, conceived by at least 2 different conception methods. Outcomes were mean birthweight, small and large for gestational age, mean gestational age, preterm (<37 weeks, versus ≥37), and very preterm birth (<32 weeks, versus ≥32). Singletons born after fresh-ET had lower mean birthweight (-51 g, 95% CI -58 to -45, p < 0.001) and increased odds of small for gestational age (odds ratio [OR] 1.20, 95% CI 1.08 to 1.34, p < 0.001), while those born after frozen-ET had higher mean birthweight (82 g, 95% CI 70 to 94, p < 0.001) and increased odds of large for gestational age (OR 1.84, 95% CI 1.56 to 2.17, p < 0.001), compared to naturally conceived siblings. Conventional population analyses gave similar results. Compared to naturally conceived siblings, mean gestational age was lower after fresh-ET (-1.0 days, 95% CI -1.2 to -0.8, p < 0.001), but not after frozen-ET (0.3 days, 95% CI 0.0 to 0.6, p = 0.028). There were increased odds of preterm birth after fresh-ET (OR 1.27, 95% CI 1.17 to 1.37, p < 0.001), and in most models after frozen-ET, versus naturally conceived siblings, with somewhat stronger associations in population analyses. For very preterm birth, population analyses showed increased odds for both fresh-ET (OR 2.03, 95% CI 1.90 to 2.12, p < 0.001) and frozen-ET (OR 1.66, 95% CI 1.42 to 1.94, p < 0.001) compared with natural conception, but results were notably attenuated within siblings (OR 1.18, 95% CI 1.0 to 1.41, p = 0.059, and OR 0.92, 95% CI 0.67 to 1.27, p = 0.6, for fresh-ET and frozen-ET, respectively). Sensitivity analyses in full siblings, in siblings born within 3-year interval, by birth order, and restricting to single embryo transfers and blastocyst transfers were consistent with the main analyses. Main limitations were high proportions of missing data on maternal body mass index and smoking. CONCLUSIONS: We found that infants conceived by fresh-ET had lower birthweight and increased odds of small for gestational age, and those conceived by frozen-ET had higher birthweight and increased odds of large for gestational age. Conception by either fresh-ET or frozen-ET was associated with increased odds of preterm birth. That these findings were observed within siblings, as well as in conventional multivariable population analyses, reduces the likelihood that they are explained by confounding or selection bias. TRIAL REGISTRATION: ClinicalTrials.gov ISRCTN11780826.

Cardiovascular disease, obesity, and type 2 diabetes in children born after assisted reproductive technology: A population-based cohort study.

BACKGROUND: Some earlier studies have found indications of significant changes in cardiometabolic risk factors in children born after assisted reproductive technology (ART). Most of these studies are based on small cohorts with high risk of selection bias. In this study, we compared the risk of cardiovascular disease, obesity, and type 2 diabetes between singleton children born after ART and singleton children born after spontaneous conception (SC). METHODS AND FINDINGS: This was a large population-based cohort study of individuals born in Norway, Sweden, Finland, and Denmark between 1984 and 2015. Data were obtained from national ART and medical birth registers and cross-linked with data from national patient registers and other population-based registers in the respective countries. In total, 122,429 children born after ART and 7,574,685 children born after SC were included. Mean (SD) maternal age was 33.9 (4.3) years for ART and 29.7 (5.2) for SC, 67.7% versus 41.8% were primiparous, and 45.2% versus 32.1% had more than 12 years of education. Preterm birth (<37 weeks 0 days) occurred in 7.9% of children born after ART and 4.8% in children born after SC, and 5.7% versus 3.3% had a low birth weight (<2,500 g). Mean (SD) follow-up time was 8.6 (6.2) years for children born after ART and 14.0 (8.6) years for children born after SC. In total, 135 (0.11%), 645 (0.65%), and 18 (0.01%) children born after ART were diagnosed with cardiovascular disease (ischemic heart disease, cardiomyopathy, heart failure, or cerebrovascular disease), obesity or type 2 diabetes, respectively. The corresponding values were 10,702 (0.14%), 30,308 (0.74%), and 2,919 (0.04%) for children born after SC. In the unadjusted analysis, children born after ART had a significantly higher risk of any cardiovascular disease (hazard ratio [HR] 1.24; 95% CI 1.04-1.48; p = 0.02), obesity (HR 1.13; 95% CI 1.05-1.23; p = 0.002), and type 2 diabetes (HR 1.71; 95% CI 1.08-2.73; p = 0.02). After adjustment, there was no significant difference between children born after ART and children born after SC for any cardiovascular disease (adjusted HR [aHR]1.02; 95% CI 0.86-1.22; p = 0.80) or type 2 diabetes (aHR 1.31; 95% CI 0.82-2.09; p = 0.25). For any cardiovascular disease, the 95% CI was reasonably narrow, excluding effects of a substantial magnitude, while the 95% CI for type 2 diabetes was wide, not excluding clinically meaningful effects. For obesity, there was a small but significant increased risk among children born after ART (aHR 1.14; 95% CI 1.06-1.23; p = 0.001). Important limitations of the study were the relatively short follow-up time, the limited number of events for some outcomes, and that the outcome obesity is often not considered as a disease and therefore not caught by registers, likely leading to an underestimation of obesity in both children born after ART and children born after SC. CONCLUSIONS: In this study, we observed no difference in the risk of cardiovascular disease or type 2 diabetes between children born after ART and children born after SC. For obesity, there was a small but significant increased risk for children born after ART. TRIAL REGISTRATION NUMBER: ISRCTN11780826.

Monitoring serum estradiol levels in breast cancer patients during extended adjuvant letrozole treatment after five years of tamoxifen: a prospective trial.

PURPOSE: To analyze whether monitoring serum estradiol (E2) levels using a highly sensitive and specific liquid chromatography tandem mass spectrometry (LC-MS/MS) method may identify patients with AI failure with E2 levels below the lower limit of quantification (LLOQ) after schwitching from tamoxifen to letrozole. METHODS: In a prospective study of breast cancer patients switching to letrozole treatment after previous tamoxifen, plasma estrogen levels were measured at baseline and after 3- and 12-months using LC-MS/MS. RESULTS: Forty-six patients were classified postmenopausal and entered into the final analysis. Thirty-nine (85%) patients had three- and 12-month E2 concentrations below the LLOQ (5 pmol/L). In the seven patients classified as AI-failures during letrozole treatment, serum E2-MS level rose above 5 pmol/L at 3 months with a mean E2-MS 77.5 pmol/L or 12 months with a mean E2-MS 21 pmol/L. None of the baseline variables i.e., age at diagnosis, age at study entry, age at menarche, BMI, endometrial thickness, total ovarian volume, baseline FSH, E2-IA, or E2-MS were significantly associated with the risk of AI failure in logistic regression. E2 levels at baseline measured by E2-IA did not significantly correlate to the levels measured by E2-MS. CONCLUSIONS: There is a relatively high risk of inadequate estrogen suppression in patients who switch from tamoxifen treatment to AIs. The use of sensitive and specific assays, such as LC-MS/MS methods, to monitor estrogen levels during AI treatment is essential to minimize the risk of a proceeding inefficient endocrine therapy.

Cerebral palsy in ART children has declined substantially over time: a Nordic study from the CoNARTaS group.

STUDY QUESTION: Are the decreasing multiple birth rates after ART associated with a simultaneous drop in the incidence of cerebral palsy (CP) in ART children over time? SUMMARY ANSWER: The relative odds of CP in ART children have declined in the Nordic countries over the past two decades concurrently with declining multiple birth rates. WHAT IS KNOWN ALREADY: In the Nordic countries, the rate of twin pregnancies after ART has decreased from 30% in the early 1990s to 4-13% in 2014, following the implementation of elective single embryo transfer (SET). Consequently, preterm birth rates have declined substantially in ART pregnancies. However, whether the risk of CP, a known consequence of preterm birth, has decreased correspondingly is still unknown. STUDY DESIGN, SIZE, DURATION: Retrospective register-based cohort study based on data on all singletons, twins, and higher-order multiples born in Denmark (birth year 1994-2010), Finland (1990-2010), and Sweden (1990-2014), corresponding to 111 844 ART children and 4 679 351 spontaneously conceived children. PARTICIPANTS/MATERIAL, SETTING, METHODS: Data were obtained from a large Nordic cohort of children born after ART and spontaneous conception initiated by the Committee of Nordic ART and Safety-CoNARTaS. The CoNARTaS cohort was established by cross-linking national register data using the unique personal identification number, allocated to every citizen in the Nordic countries. Data from the National Medical Birth Registers, where information on maternal, obstetric, and perinatal outcomes is recorded, were cross-linked to data from the National ART- and Patients Registers to obtain information on fertility treatments and CP diagnoses. Relative risks of CP for ART compared to spontaneous conception were estimated as odds ratios from multivariate logistic regression analyses across all birth years, as well as for the following birth year categories: 1990-1993, 1994-1998, 1999-2002, 2003-2006, 2007-2010, and 2011-2014. Analyses were made for all children and for singletons and twins, separately. MAIN RESULTS AND THE ROLE OF CHANCE: The main outcome measure was the relative odds of CP in different time periods for ART versus spontaneously conceived children. CP was diagnosed in 661 ART children and 16 478 spontaneously conceived children born between 1990 and 2014. In 1990-1993, the relative odds of CP were substantially higher in all ART children (adjusted odds ratio (aOR) 2.76 (95% CI 2.03-3.67)) compared with all spontaneously conceived children, while in 2011-2014, it was only moderately higher (aOR 1.39 (95% CI 1.01-1.87)). In singletons, the higher relative odds of CP in ART children diminished over time from 1990 to 1993 (aOR 2.02 (95% CI 1.22-3.14)) to 2003-2006 (aOR 1.18 (95% CI 0.91-1. 49)) and was not significantly increased for birth cohorts 2007-2010 and 2011-2014. For ART twins versus spontaneously conceived twins, the relative odds of CP was not statistically significantly increased throughout the study period. LIMITATIONS, REASONS FOR CAUTION: The main limitation of the study was a shorter follow-up time and younger age at first CP diagnosis for ART children compared with spontaneously conceived children. However, analyses ensuring a minimum of bias from differences in age at CP diagnosis and follow-up time confirmed the results, hence, we do not consider this to cause substantial bias. WIDER IMPLICATIONS OF THE FINDINGS: A SET policy in ART treatments has the potential to reduce the increased risk of cerebral palsy in the ART population due to lower rates of multiple deliveries. At a time with high survival rates of frozen/thawed embryos, this study provides a strong argument against the continued use of multiple embryo transfer in most ART settings. Larger cohort studies including also the number of gestational sacs in early pregnancy will be preferable to show an effect of vanishing twins on the risk of CP in the ART population. STUDY FUNDING/COMPETING INTEREST(S): The study was financed by grants from NordForsk (grant number 71450), Elsass Foundation (19-3-0444), the ALF-agreement (ALFGBG 70940), and The Research Fund of Rigshospitalet, Copenhagen University Hospital. There are no conflicts of interest to declare. TRIAL REGISTRATION NUMBER: ISRCTN11780826.

Childhood growth of term singletons born after frozen compared with fresh embryo transfer.

RESEARCH QUESTION: Is the growth of term singletons born after frozen embryo transfer (FET) comparable to those born after fresh embryo transfer and natural conception up to 5 years of age? DESIGN: Observational cohort study in an academic medical centre and municipal child health clinics with repeated measurements carried out by medical professionals. Term singletons born after FET (n = 110) and fresh embryo transfer (n = 181) and their matched natural conception controls (n = 543) born in Oulu, Northern Finland, were included. Mean weights, lengths, heights and head circumferences at the ages of 4, 8 and 18 months and 3 and 5 years were compared. At 3 and 5 years, body mass indices were compared. RESULTS: Childhood growth did not differ between term singletons born after FET, fresh embryo transfer and natural conception, correcting for exact age at measurement and adjusting for maternal body mass index and paternal height. CONCLUSIONS: Similar growth between children born after FET, fresh embryo transfer and natural conception offers reassurance of the safety and feasibility of the steadily increasing use of embryo cryopreservation in assisted reproduction.

Use of fertility drugs in early-onset female cancer survivors-A Finnish register-based study on 8,929 survivors.

Advances in multimodality cancer treatments have increased the risk of long-term complications in early-onset cancer survivors. For female cancer survivors, these include diminished reproductive function, often resulting in a narrowed fertile window. The aim of our study was to evaluate the use of fertility treatments in cancer survivors (aged 0-39 years at diagnosis) compared to siblings. Data from Finnish registers on cancer, birth and prescribed medications were merged to identify 8,929 survivors and 9,495 siblings without previous deliveries. Fertility drug purchases from 1993 to 2012 at the age of 16-41 years were included. A Poisson regression model was used to estimate incidence rate ratios (IRRs) for the use of fertility drugs, adjusting for age and calendar time at fertility drug purchase. Fertility treatments were more common in survivors compared to siblings, as 6.1% of survivors compared to 3.8% of siblings had bought fertility drugs (IRR 1.43, 95% confidence interval [CI] 1.25-1.65). A subclassification of fertility treatments into ovulation inductions and assisted reproductive technology (ART), showed increased use of ART (IRR 2.41, 95% CI 1.97-2.96), whereas the use of ovulation induction was similar in survivors and siblings. Analyses by calendar time periods showed the use of ART to be significantly higher in the most recent decade, from 2003 onwards. We conclude that cancer survivors have an increased risk for subfertility, which is why fertility counseling is important. However, our results mirror a more active approach among clinicians towards fertility treatments in cancer survivors during the most recent years.

Prevalence and persistence of Chlamydia trachomatis-specific antibodies after occasional and recurrent infections.

OBJECTIVES: Population-based Chlamydia trachomatis seroepidemiological studies help to identify trends in chlamydia infection. However, an improved understanding of the antibody response to infection is required when using serology to estimate cumulative incidence. Thus, the objectives of this longitudinal, retrospective, biobank-based study were to assess the appearance and persistence of C. trachomatis major outer membrane protein (MOMP)-specific serum IgG antibodies after infection and to evaluate the role of antibodies in providing protective immunity against recurrent infection. METHODS: Data of notified C. trachomatis infections in Finland were obtained from the National Infectious Diseases Register. Serum samples were acquired from the Finnish Maternity Cohort. 411 women with single chlamydia infection and 62 women with recurrent infections, and for whom suitable paired serum samples were available, were included in the study. Antibody appearance, persistence after infection and the impact of recurrent infections were evaluated. IgG antibodies specific for MOMP were measured from serum using an ELISA method. RESULTS: Anti-C. trachomatis MOMP-specific IgG antibodies were detected in 65.5% (269/411) of women within 3 months of notification of infection. In the absence of recurrent infection, seroprevalence declined to 34.5% (142/411) 3-10 years after the initial infection. The serum antibody levels at baseline correlated positively with seroprevalence at follow-up. Reinfection boosted the humoral immune response by increasing seroprevalence and the serum antibody levels. Seroprevalence within 3 months after first notification of infection was 65.5% (19/29) in women who were later diagnosed with recurrent infection, comparable with women with single notification of infection (65.5%, 269/411). CONCLUSIONS: Approximately one-third of women with single notification of chlamydia infection remain seropositive 3-10 years after the initial infection. The concentration of antibodies remained stable during the follow-up. Recurrent infection boosted the humoral immune response, but reinfection occurred despite the presence of pre-existing antibodies.

Time trends in placenta-mediated pregnancy complications after assisted reproductive technology in the Nordic countries.

BACKGROUND: The use of assisted reproductive technology is increasing worldwide and conception after assisted reproduction currently comprises 3%-6% of birth cohorts in the Nordic countries. The risk of placenta-mediated pregnancy complications is greater after assisted reproductive technology compared with spontaneously conceived pregnancies. Whether the excess risk of placenta-mediated pregnancy complications in pregnancies following assisted reproduction has changed over time, is unknown. OBJECTIVES: To investigate whether time trends in risk of pregnancy complications (hypertensive disorders in pregnancy, placental abruption and placenta previa) differ for pregnancies after assisted reproductive technology compared with spontaneously conceived pregnancies during 3 decades of assisted reproduction treatment in the Nordic countries. STUDY DESIGN: In a population-based cohort study, with data from national health registries in Denmark (1994-2014), Finland (1990-2014), Norway (1988-2015) and Sweden (1988-2015), we included 6,830,578 pregnancies resulting in delivery. Among these, 146,998 (2.2%) were pregnancies after assisted reproduction (125,708 singleton pregnancies, 20,668 twin pregnancies and 622 of higher order plurality) and 6,683,132 (97.8%) pregnancies were conceived spontaneously (6,595,185 singleton pregnancies, 87,106 twin pregnancies and 1,289 of higher order plurality). We used logistic regression with post-estimation to estimate absolute risks and risk differences for each complication. We repeated analyses for singleton and twin pregnancies, separately. In subsamples with available information, we also adjusted for maternal body mass index, smoking during pregnancy, previous cesarean delivery, culture duration, and cryopreservation. RESULTS: The risk of each placental complication was consistently greater in pregnancies following assisted reproductive technology compared with spontaneously conceived pregnancies across the study period, except for hypertensive disorders in twin pregnancies, where risks were similar. Risk of hypertensive disorders increased over time in twin pregnancies for both conception methods, but more strongly for pregnancies following assisted reproductive technology (risk difference, 1.73 percentage points per 5 years; 95% confidence interval, 1.35-2.11) than for spontaneously conceived twins (risk difference, 0.75 percentage points; 95% confidence interval, 0.61-0.89). No clear time trends were found for hypertensive disorders in singleton pregnancies. Risk of placental abruption decreased over time in all groups. Risk differences were -0.16 percentage points (95% confidence interval, -0.19 to -0.12) and -0.06 percentage points (95% confidence interval, -0.06 to -0.05) for pregnancies after assisted reproduction and spontaneously conceived pregnancies, respectively, for singletons and multiple pregnancies combined. Over time, the risk of placenta previa increased in pregnancies after assisted reproduction among both singletons (risk difference, 0.21 percentage points; 95% confidence interval, 0.14-0.27) and twins (risk difference, 0.30 percentage points; 95% confidence interval, 0.16-0.43), but remained stable in spontaneously conceived pregnancies. When adjusting for culture duration, the temporal increase in placenta previa became weaker in all groups of assisted reproductive technology pregnancies, whereas adjustment for cryopreservation moderately attenuated trends in assisted reproductive technology twin pregnancies. CONCLUSIONS: The risk of placenta-mediated pregnancy complications following assisted reproductive technology remains higher compared to spontaneously conceived pregnancies, despite declining rates of multiple pregnancies. For hypertensive disorders in pregnancy and placental abruption, pregnancies after assisted reproduction follow the same time trends as the background population, whereas for placenta previa, risk has increased over time in pregnancies after assisted reproductive technology.

Plasma pentraxin 3 is higher in early ovarian hyperstimulation syndrome than in uncomplicated in vitro fertilization cycle of high-risk women.

PURPOSE: Pentraxin 3 (PTX3) is a locally secreted, quicker responsive pro-inflammatory protein than C-reactive protein (CRP). We evaluated the value of PTX3 in the prediction of ovarian hyperstimulation syndrome (OHSS), a severe complication of in vitro fertilization (IVF). METHODS: This two-year prospective follow-up study included 27 women with uncomplicated IVF-cycles (IVF group) and 31 patients diagnosed with moderate or severe early OHSS (OHSS group). PTX3 was analysed from follicular fluid (FF) and serial blood samples with enzyme-linked immunoassay and CRP with particle-enhanced immunoturbidimetric assay. The value of PTX3 and CRP in detecting OHSS was examined with receiver operating characteristic (ROC) curve analysis and expressed as the area under the curve (AUC). RESULTS: The circulating PTX3 level peaked at two days after oocyte pick-up (OPU2), and in the OHSS group the level was 1.9 times higher (P = 0.006) than in the IVF group. However, in ROC curve analysis PTX3 (AUC 0.79, best cut off 1.1 µg/L) was not superior to CRP (AUC 0.87; best cut off 9.5 mg/L) in predicting early OHSS. In the IVF group, the FF-PTX3 concentration was 15-20 times higher than in the plasma. PTX3 level at OPU2 correlated with the number of punctured follicles (r = 0.56, n = 22, P = 0.006). Triggering with human chorionic gonadotrophin or early pregnancy had no effect on PTX3 level. CONCLUSION: The elevated PTX3 concentration in OHSS at OPU2, when freeze-all embryos strategy is still possible to consider, indicates that PTX3 level could provide additional benefit in the risk assessment for early OHSS.

Risk factors for preterm delivery among early onset cancer survivors: A Finnish register-based study.

Previous studies have shown an elevated risk for preterm delivery among early onset cancer survivors. Whether the preterm delivery starts spontaneously, due to possible uterine damage because of cancer treatment, or is induced due to maternal conditions is unclear. Our aim was to assess pregnancy related conditions in female cancer survivors possibly underlying the elevated risk for preterm labor. Nationwide cancer and birth registries were merged to identify 1,753 first deliveries of cancer survivors (diagnosed below 40 years of age) and 5,123 first deliveries of matched female comparison subjects between January 1991 and December 2013. Conditional logistic regression models were used to estimate the risk for pregnancy related conditions adjusting for maternal age, gestational age and smoking. We found an overall increased risk for hospitalization during pregnancy (OR 1.45, 95% CI 1.25-1.68), intrahepatic cholestasis (OR 2.86, 95% CI 1.09-7.49), fear of childbirth (OR 2.25, 95% CI 1.31-3.85) and mental disorders and diseases of the nervous system complicating pregnancy and labor (OR 5.89, 95% CI 2.31-15.00). Among survivors, 129 (7.4%) delivered preterm compared to 268 (5.2%) comparisons subjects (p = 0.004). We found a statistically significant increased risk for preterm delivery among cancer survivors with vaginal bleeding (OR 1.35, 95% CI 1.07-1.71) and pre-eclampsia (1.35, 95% CI 1.06-1.72) compared to comparison subjects with the same condition. Health professionals treating these women should be aware of these risks. In general, however, our results are reassuring when it comes to pregnancies among cancer survivors.

Perinatal and maternal outcome after vitrification of blastocysts: a Nordic study in singletons from the CoNARTaS group.

STUDY QUESTION: Is transfer of vitrified blastocysts associated with higher perinatal and maternal risks compared with slow-frozen cleavage stage embryos and fresh blastocysts? SUMMARY ANSWER: Transfer of vitrified blastocysts is associated with a higher risk of preterm birth (PTB) when compared with slow-frozen cleavage stage embryos and with a higher risk of a large baby, hypertensive disorders in pregnancy (HDPs) and postpartum hemorrhage (PPH) but a lower risk of placenta previa when compared with fresh blastocysts. WHAT IS KNOWN ALREADY: Transfer of frozen-thawed embryos (FETs) plays a central role in modern fertility treatment, limiting the risk of ovarian hyperstimulation syndrome and multiple pregnancies. Following FET, several studies report a lower risk of PTB, low birth weight (LBW) and small for gestational age (SGA) yet a higher risk of fetal macrosomia and large for gestational age (LGA) compared with fresh embryos. In recent years, the introduction of new freezing techniques has increased treatment success. The slow-freeze technique combined with cleavage stage transfer has been replaced by vitrification and blastocyst transfer. Only few studies have compared perinatal and maternal outcomes after vitrification and slow-freeze and mainly in cleavage stage embryos, with most studies indicating similar outcomes in the two groups. Studies on perinatal and maternal outcomes following vitrified blastocysts are limited. STUDY DESIGN, SIZE, DURATION: This registry-based cohort study includes singletons born after frozen-thawed and fresh transfers following the introduction of vitrification in Sweden and Denmark, in 2002 and 2009, respectively. The study includes 3650 children born after transfer of vitrified blastocysts, 8123 children born after transfer of slow-frozen cleavage stage embryos and 4469 children born after transfer of fresh blastocysts during 2002-2015. Perinatal and maternal outcomes in singletons born after vitrified blastocyst transfer were compared with singletons born after slow-frozen cleavage stage transfer and singletons born after fresh blastocyst transfer. Main outcomes included PTB, LBW, macrosomia, HDP and placenta previa. PARTICIPANTS/MATERIALS, SETTING, METHODS: Data were obtained from the CoNARTaS (Committee of Nordic ART and Safety) group. Based on national registries in Sweden, Finland, Denmark and Norway, the CoNARTaS cohort includes all children born after ART treatment in public and private clinics 1984-2015. Outcomes were assessed with logistic multivariable regression analysis, adjusting for the country and year of birth, maternal age, body mass index, parity, smoking, parental educational level, fertilisation method (IVF/ICSI), single embryo transfer, number of gestational sacs and the child's sex. MAIN RESULTS AND THE ROLE OF CHANCE: A higher risk of PTB (<37 weeks) was noted in the vitrified blastocyst group compared with the slow-frozen cleavage stage group (adjusted odds ratio, aOR [95% CI], 1.33 [1.09-1.62]). No significant differences were observed for LBW (<2500 g), SGA, macrosomia (≥4500 g) and LGA when comparing the vitrified blastocyst with the slow-frozen cleavage stage group. For maternal outcomes, no significant difference was seen in the risk of HDP, placenta previa, placental abruption and PPH in the vitrified blastocyst versus the slow frozen cleavage stage group, although the precision was limited.When comparing vitrified and fresh blastocysts, we found higher risks of macrosomia (≥4500 g) aOR 1.77 [1.35-2.31] and LGA aOR 1.48 [1.18-1.84]. Further, the risks of HDP aOR 1.47 [1.19-1.81] and PPH aOR 1.68 [1.39-2.03] were higher in singletons born after vitrified compared with fresh blastocyst transfer while the risks of SGA aOR 0.58 [0.44-0.78] and placenta previa aOR 0.35 [0.25-0.48] were lower. LIMITATIONS, REASONS FOR CAUTION: Since vitrification was introduced simultaneously with blastocyst transfer in Sweden and Denmark, it was not possible to explore the effect of vitrification per se in this study. WIDER IMPLICATIONS OF THE FINDINGS: The results from the change of strategy to vitrification of blastocysts are reassuring, indicating that the freezing technique per se has no major influence on the perinatal and maternal outcomes. The higher risk of PTB may be related to the extended embryo culture rather than vitrification. STUDY FUNDING/COMPETING INTEREST(S): The study is part of the ReproUnion Collaborative study, co-financed by the European Union, Interreg V ÖKS. The study was also financed by grants from the Swedish state under the agreement between the Swedish government and the county councils, the ALF agreement (LUA/ALF 70940), Hjalmar Svensson Research Foundation and NordForsk (project 71 450). There are no conflicts of interest to declare. TRIAL REGISTRATION NUMBER: ISRCTN11780826.

A cohort study of 49 933 women with surgically verified endometriosis: Increased incidence of breast cancer below the age of 40.

INTRODUCTION: The association between endometriosis and breast cancer is unclear. We assessed the risk of breast cancer in women with surgically verified endometriosis, with special focus on the age at cancer diagnosis, time from endometriosis diagnosis and breast cancer histology. MATERIAL AND METHODS: All women with first endometriosis-associated diagnoses occurring concomitantly with relevant surgical codes during 1987-2012 were retrieved from the Finnish Hospital Discharge Register in Finland. Breast cancers diagnosed after the endometriosis diagnosis were identified from the Finnish Cancer Registry. The Finnish female population served as the reference. The endometriosis cohort consisted of 49 933 women (23 210 cases of ovarian, 20 187 peritoneal and 2372 deep infiltrating endometriosis). The outcome measure was the standardized incidence ratio (SIR) with 95% confidence interval (95% CI) of breast cancer calculated for the whole cohort and for the subtypes of endometriosis, stratified by the age at breast cancer diagnosis, histology and time from endometriosis diagnosis. RESULTS: The overall risk of breast cancer (1555 cases) was similar to the reference population (SIR 0.99; 95% CI 0.94-1.03), did not differ in types of endometriosis, and was similar for ductal and lobular breast cancer. However, the SIR of breast cancer was increased in the age group of 20-29 years (SIR 4.44; 95% CI 2.22-7.94) and in the age group of 30-39 years (SIR 1.28; 95% CI 1.03-1.57). The risk of in situ breast cancer (170 cases) was increased in the entire endometriosis cohort (SIR 1.25; 95% CI 1.07-1.44). CONCLUSIONS: The overall risk of breast cancer in women with surgically verified endometriosis was similar to that of general population. However, the risk of breast cancer at young age was increased. Young women with surgically verified endometriosis represent highly symptomatic patients with more frequent surgeries and additional therapies that might also contribute to the risk of breast cancer.

Hormone profiling, including anti-Müllerian hormone (AMH), for the diagnosis of polycystic ovary syndrome (PCOS) and characterization of PCOS phenotypes.

Objective was to evaluate serum anti-Müllerian hormone (AMH) levels in polycystic ovary syndrome (PCOS) and in its different phenotypes in relation to clinical, endocrine and metabolic parameters using a new automated VIDAS® method and to compare it with the Gen II method. Study design was multi-center study including 319 PCOS women and 109 healthy controls. Serum AMH levels measured using VIDAS® were significantly higher in PCOS women than controls (p < .001), and they correlated with those measured using the AMH Gen II method. An AMH cutoff value of 42.1 pmol/L distinguished PCOS women from controls with 67% sensitivity and 83% specificity. The PCOS women with three Rotterdam criteria or hyperandrogenism displayed significantly higher AMH levels compared with those with two Rotterdam criteria or normoandrogenism. In PCOS, AMH levels correlated positively with luteinizing hormone (LH), androgen and sex hormone-binding globulin (SHBG) levels and negatively with BMI, abdominal obesity, follicle-stimulating hormone (FSH), fasting glucose and insulin, and insulin resistance. In conclusion, AMH evaluated using the VIDAS® method distinguished PCOS patients from healthy controls relatively well, especially in those with more severe phenotypes. Further studies are needed to establish whether AMH measurements can distinguish PCOS patients with different metabolic risk factors.