Higher risk of pre-eclampsia and other vascular disorders with artificial cycle for frozen-thawed embryo transfer compared to ovulatory cycle or to fresh embryo transfer following in vitro fertilization.

Background: Risks of maternal morbidity are known to be reduced in pregnancies resulting from frozen embryo transfer (FET) compared to fresh-embryo transfer (fresh-ET), except for the risk of pre-eclampsia, reported to be higher in FET pregnancies compared to fresh-ET or natural conception. Few studies have compared the risk of maternal vascular morbidities according to endometrial preparation for FET, either with ovulatory cycle (OC-FET) or artificial cycle (AC-FET). Furthermore, maternal pre-eclampsia could be associated with subsequent vascular disorders in the offspring. Methods: A 2013-2018 French nationwide cohort study comparing maternal vascular morbidities in 3 groups of single pregnancies was conducted: FET with either OC or AC preparation, and fresh-ET. Data were extracted from the French National Health System database. Results were adjusted for maternal characteristics and infertility (age, parity, smoking, obesity, history of diabetes or hypertension, endometriosis, polycystic ovary syndrome and premature ovarian insufficiency). Results: A total of 68025 single deliveries were included: fresh-ET (n=48152), OC-FET (n=9500), AC-FET (n=10373). The risk of pre-eclampsia was higher in AC-FET compared to OC-FET and fresh-ET groups in univariate analysis (5.3% vs. 2.3% and 2.4%, respectively, P<0.0001). In multivariate analysis the risk was significantly higher in AC-FET compared to fresh-ET: aOR=2.43 [2.18-2.70], P<0.0001). Similar results were observed for the risk of other vascular disorders in univariate analysis (4.7% vs. 3.4% and 3.3%, respectively, P=0.0002) and in multivariate analysis (AC-FET compared to fresh-ET: aOR=1.50 [1.36-1.67], P<0.0001). In multivariate analysis, the risk of pre-eclampsia and other vascular disorders were comparable in OC-FET and fresh-ET: aOR=1.01 [0.87-1.17, P= 0.91 and aOR=1.00 [0.89-1.13], P=0.97, respectively).Within the group of FET, the risks of pre-eclampsia and other vascular disorders in multivariate analysis were higher in AC-FET compared to OC-FET (aOR=2.43 [2.18-2.70], P<0.0001 and aOR=1.5 [1.36-1.67], P<0.0001, respectively). Conclusion: This nationwide register-based cohort study highlights the possibly deleterious role of prolonged doses of exogenous estrogen-progesterone supplementation on gestational vascular pathologies and the protective role of the corpus luteum present in OC-FET for their prevention. Since OC-FET has been demonstrated not to strain the chances of pregnancy, OC preparation should be advocated as first-line preparation in FET as often as possible in ovulatory women.

Risk factors associated with preterm birth in singletons born after IVF: a national cohort study.

RESEARCH QUESTION: What are the risk factors for prematurity other than intrauterine growth restriction in singletons after IVF? DESIGN: Data were collected from a national registry, based on an observational prospective cohort of 30,737 live births after assisted reproductive technology (fresh embryo transfers: n = 20,932 and frozen embryo transfer [FET] n = 9805) between 2014 and 2015. A population of not-small for gestational age singletons conceived after fresh embryo transfers and FET, and their parents, was selected. Data on a number of variables were collected, including type of infertility, number of oocytes retrieved and vanishing twins. RESULTS: Preterm birth occurred in 7.7% (n = 1607) of fresh embryo transfers and 6.2% (n = 611) of frozen-thawed embryo transfers (P < 0.0001; adjusted odds ratio [aOR] = 1.34 [1.21-1.49]). Endometriosis and vanishing twin increased the risk of preterm birth after fresh embryo transfer (P < 0.001; aOR 1.32 and 1.78, respectively). Polycystic ovaries or more than 20 oocytes retrieved also increased preterm birth risk (aOR 1.31 and 1.30; P = 0.003 and P = 0.02, respectively); large oocyte cohort (>20) was no longer associated with the risk of prematurity in FET. CONCLUSION: Endometriosis remains a risk for prematurity even in the absence of intrauterine growth retardation, which suggests a dysimmune effect. Large oocyte cohorts obtained by stimulation, without clinical polycystic ovary syndrome diagnosed before attempts, do not affect FET outcomes, reinforcing the idea of a phenotypic difference in the clinical presentation of polycystic ovary syndrome.

Obstetrical outcomes and maternal morbidities associated with COVID-19 in pregnant women in France: A national retrospective cohort study.

BACKGROUND: To the best of our knowledge, no study has exhaustively evaluated the association between maternal morbidities and Coronavirus Disease 2019 (COVID-19) during the first wave of the pandemic in pregnant women. We investigated, in natural conceptions and assisted reproductive technique (ART) pregnancies, whether maternal morbidities were more frequent in pregnant women with COVID-19 diagnosis compared to pregnant women without COVID-19 diagnosis during the first wave of the COVID-19 pandemic. METHODS AND FINDINGS: We conducted a retrospective analysis of prospectively collected data in a national cohort of all hospitalizations for births ≥22 weeks of gestation in France from January to June 2020 using the French national hospitalization database (PMSI). Pregnant women with COVID-19 were identified if they had been recorded in the database using the ICD-10 (International Classification of Disease) code for presence of a hospitalization for COVID-19. A total of 244,645 births were included, of which 874 (0.36%) in the COVID-19 group. Maternal morbidities and adverse obstetrical outcomes among those with or without COVID-19 were analyzed with a multivariable logistic regression model adjusted on patient characteristics. Among pregnant women, older age (31.1 (±5.9) years old versus 30.5 (±5.4) years old, respectively, p < 0.001), obesity (0.7% versus 0.3%, respectively, p < 0.001), multiple pregnancy (0.7% versus 0.4%, respectively, p < 0.001), and history of hypertension (0.9% versus 0.3%, respectively, p < 0.001) were more frequent with COVID-19 diagnosis. Active smoking (0.2% versus 0.4%, respectively, p < 0.001) and primiparity (0.3% versus 0.4%, respectively, p < 0.03) were less frequent with COVID-19 diagnosis. Frequency of ART conception was not different between those with and without COVID-19 diagnosis (p = 0.28). When compared to the non-COVID-19 group, women in the COVID-19 group had a higher frequency of admission to ICU (5.9% versus 0.1%, p < 0.001), mortality (0.2% versus 0.005%, p < 0.001), preeclampsia/eclampsia (4.8% versus 2.2%, p < 0.001), gestational hypertension (2.3% versus 1.3%, p < 0.03), postpartum hemorrhage (10.0% versus 5.7%, p < 0.001), preterm birth at <37 weeks of gestation (16.7% versus 7.1%, p < 0.001), <32 weeks of gestation (2.2% versus 0.8%, p < 0.001), <28 weeks of gestation (2.4% versus 0.8%, p < 0.001), induced preterm birth (5.4% versus 1.4%, p < 0.001), spontaneous preterm birth (11.3% versus 5.7%, p < 0.001), fetal distress (33.0% versus 26.0%, p < 0.001), and cesarean section (33.0% versus 20.2%, p < 0.001). Rates of pregnancy terminations ≥22 weeks of gestation, stillbirths, gestational diabetes, placenta praevia, and placenta abruption were not significantly different between the COVID-19 and non-COVID-19 groups. The number of venous thromboembolic events was too low to perform statistical analysis. A limitation of this study relies in the possibility that asymptomatic infected women were not systematically detected. CONCLUSIONS: We observed an increased frequency of pregnant women with maternal morbidities and diagnosis of COVID-19 compared to pregnant women without COVID-19. It appears essential to be aware of this, notably in populations at known risk of developing a more severe form of infection or obstetrical morbidities and in order for obstetrical units to better inform pregnant women and provide the best care. Although causality cannot be determined from these associations, these results may be in line with recent recommendations in favor of vaccination for pregnant women.

Do in vitro fertilization, intrauterine insemination or female infertility impact the risk of congenital anomalies in singletons? A longitudinal national French study.

STUDY QUESTION: Do IVF, IUI or female infertility (i.e. endometriosis, polycystic ovary syndrome [PCOS] and primary ovarian insufficiency [POI]) lead to an increased risk of congenital anomalies in singletons? SUMMARY ANSWER: After multivariable adjustments, the increased risks of congenital defects associated with IUI were no longer significant, but the underlying maternal infertility presented a potential emental risk, in addition to the risk associated with IVF. WHAT IS KNOWN ALREADY: Most epidemiological studies suggest that singletons born from ART have a higher risk of birth defects, specifically musculoskeletal, cardiovascular and urogenital disorders. However, most of these studies were established on data obtained at birth or in the neonatal period and from relatively small populations or several registries. Moreover, to our knowledge, female infertility, which is a potential confounder, has never been included in the risk assessment. STUDY DESIGN, SIZE, DURATION: Using data from the French National Health System database, we conducted a comparative analysis of all singleton births (deliveries ≥22 weeks of gestation and/or >500 g of birthweight) in France over a 5-year period (2013-2017) resulting from fresh embryo or frozen embryo transfer (fresh-ET or FET from IVF/ICSI cycles), IUI and natural conception (NC). Data were available for this cohort of children at least up to early childhood (2.5 years old). PARTICIPANTS/MATERIALS, SETTING, METHODS: A total of 3 501 495 singleton births were included (3 417 089 from NC, 20 218 from IUI, 45 303 from fresh-ET and 18 885 from FET). Data were extracted from national health databases and used to identify major birth defects. Malformations were classified according to the 10th revision of the International Classification of Disease. To analyse the effect of mode of conception, multivariable analyses were performed with multiple logistic regression models adjusted for maternal age, primiparity, obesity, smoking, history of high blood pressure or diabetes and female infertility. MAIN RESULTS AND THE ROLE OF CHANCE: In our cohort of children, the overall prevalence of congenital malformations was 3.78% after NC, 4.53% after fresh-ET, 4.39% after FET and 3.91% after IUI (132 646 children with major malformations). Compared with infants conceived naturally, children born after fresh-ET and after FET had a significantly higher prevalence of malformations, with an adjusted odds ratio (aOR) of 1.15 [95% CI 1.10-1.20, P < 0.0001] and aOR of 1.13 [95% CI 1.05-1.21, P = 0.001], respectively. Among the 15 relevant subgroups of malformations studied, we observed a significantly increased risk of eight malformations in the fresh-ET group compared with the NC group (i.e. musculoskeletal, cardiac, urinary, digestive, neurological, cleft lip and/or palate and respiratory). In the FET group, this increased risk was observed for digestive and facial malformations. The overall risk of congenital malformations, and the risk by subtype, was similar in the IUI group and the NC group (overall risk: aOR of 1.01 [95% CI 0.94-1.08, P = 0.81]). In addition, there was an overall independent increase in the risk of congenital defects when the mothers were diagnosed with endometriosis (1.16 aOR [95% CI 1.10-1.22], P < 0.0001), PCOS (1.20 aOR [95% CI 1.08-1.34], P = 0.001) or POI (1.52 aOR [95% CI 1.23-1.88], P = 0.0001). Chromosomal, cardiac and neurological anomalies were more common in the three maternal infertility groups. LIMITATIONS, REASONS FOR CAUTION: Male infertility, the in vitro fertilization method (i.e. in vitro fertilization without or with sperm injection: conventional IVF vs ICSI) and embryo stage at transfer could not be taken into account. Furthermore, residual confounding cannot be excluded as well as uncertainties regarding the diagnostic criteria used for the three female infertilities. Findings for specific malformations should be interpreted with caution because the number of cases was small in some sub-groups (potentially due to the Type I error or multiple testing). WIDER IMPLICATIONS OF THE FINDINGS: In this large study, after multivariable maternal adjustments, a moderately increased risk of defects subsisted after IVF, while those associated with IUI were no longer significant. In addition, our results showed that underlying maternal infertility could contribute to the increased risk of defects associated with IVF. These novel findings highlight the importance of taking into account the ART treatment methods and the type of infertility. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by the National Agency of Biomedicine. The authors have no competing interests to disclose. TRIAL REGISTRATION NUMBER: NA.

Reproductive technologies, female infertility, and the risk of imprinting-related disorders.

BACKGROUND: Epidemiological studies suggest that singletons born from assisted reproductive technologies (ART) have a high risk of adverse perinatal outcomes, specifically for imprinting disorders. Because ART processes take place at times when epigenetic reprogramming/imprinting are occurring, there is concern that ART can affect genomic imprints. However, little is currently known about the risk of imprinting defects according to the type of ART or the type of underlying female infertility. From the French national health database, a cohort of 3,501,495 singletons born over a 5-year period (2013-2017) following fresh embryo or frozen embryo transfers (fresh-ET or FET from in vitro fertilization), intrauterine insemination, or natural conception was followed up to early childhood. Based on clinical features, several syndromes/diseases involving imprinted genes were monitored. The effects of ART conception and the underlying cause of female infertility were assessed. RESULTS: Compared with infants conceived naturally, children born after fresh-ET had a higher prevalence of imprinting-related diseases, with an aOR of 1.43 [95% CI 1.13-1.81, p = 0.003]. Namely, we observed an increased risk of neonatal diabetes mellitus (1.96 aOR [95% CI 1.43-2.70], p < 0.001). There was an overall independent increase in risk of imprinting diseases for children with mothers diagnosed with endometriosis (1.38 aOR [95% CI 1.06-1.80], p = 0.02). Young and advanced maternal age, primiparity, obesity, smoking, and history of high blood pressure or diabetes were also associated with high global risk. CONCLUSIONS: This prospective epidemiological study showed that the risk of clinically diagnosed imprinting-related diseases is increased in children conceived after fresh embryo transfers or from mothers with endometriosis. The increased perturbations in genomic imprinting could be caused by controlled ovarian hyperstimulation and potentially endometriosis through the impairment of endometrial receptivity and placentation, leading to epigenetic feto-placental changes. Further studies are now needed to improve understanding of the underlying molecular mechanisms (i.e. genetic or epigenetic causes).

Prolonged estrogen (E2) treatment prior to frozen-blastocyst transfer decreases the live birth rate.

STUDY QUESTION: How does the duration of estrogen (E2) treatment prior to frozen-blastocyst transfers affect the live birth rate (LBR)? SUMMARY ANSWER: Prolonged E2 exposure as part of artificial endometrial preparation (AEP) significantly decreases the LBR after autologous frozen-thawed blastocyst transfer. WHAT IS KNOWN ALREADY: One effective method for endometrial preparation prior to frozen embryo transfer is AEP, a sequential regimen with E2 and progesterone, which aims to mimic the endocrine exposure of the endometrium in a normal cycle. Nevertheless, the optimal duration of E2 administration prior to transfer remains unknown. STUDY DESIGN, SIZE, DURATION: An observational cohort study was conducted in a tertiary care university hospital between 01/07/2012 and 31/12/2015. The main inclusion criteria was having a single frozen-thawed blastocyst transfer with an AEP using exogenous E2. PARTICIPANTS/MATERIALS, SETTING, METHODS: A total of 1377 frozen-thawed blastocyst transfers were assigned to four groups according to the duration of the E2 administration prior to the embryo transfers. These comprised a '≤21 days' group (n = 330), a '22-28 days' group (n = 665), a '29-35 days' group (n = 289) and a '36-48 days' group (n = 93). The '≤21 days' group' was taken as the reference group. The main measured outcome was the LBR following frozen-thawed blastocyst transfers. Statistical analysis was conducted using univariate and multivariate logistic regression models. MAIN RESULTS AND THE ROLE OF CHANCE: LBR significantly decreased when the E2 exposure prior to the frozen-thawed blastocyst transfer exceeded 28 days: OR = 0.66; 95% CI [0.46-0.95]; P = 0.026 and OR = 0.49 [0.27-0.89]; P = 0.018, respectively, for the '29 to 35 days' group and for the '36 to 48 days' group compared to the reference group. Early pregnancy loss rates significantly increased when the E2 exposure lasted more than 35 days prior to the frozen-thawed blastocyst transfer (OR = 2.37 [1.12-5.05]; P = 0.025 vs. the reference group). After multivariate logistic regression, E2 exposure lasting more than 28 days prior to the frozen-thawed blastocyst transfer was associated with a decrease in the LBR, for the '29-35 days' group (OR = 0.65; [0.45-0.95]; P = 0.044) as for the '36-48 days' group (OR = 0.49; [0.26-0.92]; P = 0.035), vs. the reference group. LIMITATIONS, REASONS FOR CAUTION: One limitation is linked to the observational design of this study. WIDER IMPLICATIONS OF THE FINDINGS: In order to give patients the best chance to obtain a live birth after frozen-thawed blastocyst transfer, the length of E2 exposure prior to the frozen-blastocyst transfer should not exceed 28 days. This study provides new insight in regard to endometrial preparation using AEP prior to frozen-blastocyst transfer. STUDY FUNDING/COMPETING INTEREST(S): No funding and no competing interest.

In women with endometriosis anti-Müllerian hormone levels are decreased only in those with previous endometrioma surgery.

STUDY QUESTION: Are anti-Müllerian hormone (AMH) levels lower in women with endometriosis, notably those with endometriomas (OMAs) and deep infiltrating lesions, compared with controls without endometriosis? SUMMARY ANSWER: Endometriosis and OMAs per se do not result in lower AMH levels. AMH levels are decreased in women with previous OMA surgery independently of the presence of current OMAs. WHAT IS KNOWN ALREADY: The impact of endometriosis and OMAs per se on the ovarian reserve is controversial. Most previous studies have been conducted in infertile women. The strength of our study lies in the following points: (i) the selection of women undergoing surgery and not only according to the presence of infertility, (ii) the classification of women with endometriosis and controls based on strict surgical and histological criteria. STUDY DESIGN, SIZE, DURATION: Cross-sectional study using data prospectively collected in all non-pregnant <42-year-old patients, who were surgically explored for a benign gynaecological condition at a university tertiary referral centre between 2004 and 2008. For each patient, a structured questionnaire was completed during a face-to-face interview conducted by the surgeon during the month preceding surgery. AMH levels were measured in serum samples drawn in the month preceding surgery, without regard to menstrual phase or hormonal therapy. PARTICIPANTS/MATERIALS, SETTING, METHODS: Operations were done on 1262 women between 2004 and 2008, of which 1133 signed the informed consent. Of the 566 women with a visual diagnosis of endometriosis, 411 had histologically proven endometriosis. Frozen serum samples for the AMH measurement were available in 313 of them. Out of the 554 women without visual endometriosis and without past endometriosis surgery, 413 had a frozen serum sample for the AMH measurement. Univariate analysis examined AMH levels according to baseline patient characteristics, the presence and type of endometriosis (superficial lesion, OMA, deep infiltrating lesion) and previous OMA surgery. Analysis of variance-covariance then examined the effects of co-variables on AMH levels. Finally, logistic regressions were conducted to examine the odds ratio (OR) of having AMH levels <1 ng/ml according to the same co-variables. MAIN RESULTS AND THE ROLE OF CHANCE: The difference in AMH levels between women with endometriosis and controls did not reach significance (3.6 ± 3.1 versus 4.1 ± 3.4 ng/ml, P = 0.06). Analysis of variance-covariance demonstrated that AMH levels significantly decreased with age (P < 0.001) and in women with prior OMA surgery irrespective of whether OMAs were present or not at the time of study (P < 0.05). Logistic regression revealed that two major factors were related to AMH levels <1 ng/ml: (i) age (compared with <29 years; 30-34 years OR = 3.1, 95% CI: 1.5-6.4, P = 0.01; 35-39 years OR = 7.0, 95% CI: 3.5-14.1, P = 0.001; ≥40 years OR = 20.8, 95% CI: 9.1-47.4, P = 0.001) and (ii) prior OMA surgery (OR = 3.0, 95% CI: 1.4-6.41, P = 0.01). LIMITATIONS, REASONS FOR CAUTION: The selection of our study population was based on a surgical diagnosis. Women with an asymptomatic form of endometriosis are therefore not included in our study. We cannot exclude that infertile women with OMAs associated with a diminished ovarian reserve, as assessed during their infertility work-up, were less likely to be referred for surgery and might therefore be underrepresented. WIDER IMPLICATIONS OF THE FINDINGS: Our findings suggest that OMAs per se do not diminish the ovarian reserve reflected by AMH levels but that alterations seen in women with endometriosis are a deleterious consequence of OMA surgery. These findings should be taken into account in the decision to operate OMAs in women with a desire for future pregnancy. STUDY FUNDING: none. Potential competing interests: none.

Use of oral contraceptives in women with endometriosis before assisted reproduction treatment improves outcomes.

In women with endometriosis, including those with endometriomas, 6 to 8 weeks of continuous use of oral contraception (OC) before assisted reproduction treatment (ART) maintains ART outcomes comparable with the outcomes of age-matched controls without endometriosis. In contrast, ART outcomes are markedly compromised in endometriosis patients who are not pretreated with OC. Ovarian responsiveness to stimulation was not altered by 6 to 8 weeks' use of pre-ART OC, including in poor responders with endometriomas.