Birthweight difference of singletons conceived through in vitro fertilization with frozen versus fresh embryo transfer: An analysis of 5406 embryo transfers in a retrospective study 2013-2018

International audienceINTRODUCTION: Perinatal risks after frozen embro transfer (FET) have been reassuring but some authors suggest that birthweights are higher after FET than after fresh embryo transfer (ET). The primary objective of this retrospective study, conducted in Clinique de la Sagesse, Rennes (France) from December 2013 to March 2017, was to determine whether a difference in birthweight exists between children conceived through in vitro fertilization (IVF) with frozen versus fresh ET. The secondary objective was to compare live birth rates after frozen versus fresh cycles.MATERIAL AND METHODS: All couples undergoing IVF were included. Cycles with gamete donation and twin pregnancies were excluded. Hormone therapy was used in all embryo transfers. The main outcome measures were the child's birthweight, mode of delivery, gestation length and sex, maternal characteristics, and IVF characteristics. The primary endpoint was birthweight.RESULTS: We studied 5406 embryo transfers and the 708 resulting singleton live births on which birthweight data were available. Mean birthweight was 3357g after frozen embryo transfer versus 3183g after fresh embryo transfer (p<0.001). After adjusting for confounding factors, the children born after frozen embryo transfer were 165.2g heavier (95%CI [92.96-237.51]). No difference was found in gestation length. Live birth was obtained after the 1.6th IVF attempt. Live birth rate was higher for fresh cycles (19% versus 12%, p<0.001), and the caesarean rate lower (16% versus 21%).DISCUSSION: Birthweight was higher after frozen embryo transfer for a similar gestational age. Further research is needed to elucidate the mechanisms responsible for this difference

Heavy metals and diminished ovarian reserve: single-exposure and mixture analyses amongst women consulting in French fertility centres

International audienceRESEARCH QUESTION: Do heavy metals affect the risk of diminished ovarian reserve (DOR) in women of reproductive age? DESIGN: A total of 139 cases and 153 controls were included between 2016 and 2020. The participants were aged between 18 and 40 years and attended consultations for couple infertility in one of four fertility centres in western France. Cases of DOR were defined as women with an antral follicle count less than 7, anti-Müllerian hormone levels 1.1 ng/ml or less, or both. Controls were frequency matched on age groups and centres, and were women with normal ovarian reserve evaluations, no malformations and menstrual cycles between 26 and 35 days. Heavy metals (lead, mercury, cadmium and chromium) were measured in whole blood at inclusion. Single-exposure associations were examined with multivariable logistic regressions adjusted on potential confounders. Mixture effects were investigated with quantile g-computation and Bayesian kernel machine regression (BKMR). RESULTS: Chromium as a continuous exposure was significantly associated with DOR in unadjusted models (OR 2.07, 95% CI 1.04 to 4.13) but the association was no longer significant when confounders were controlled for (adjusted OR 2.75, 95% CI 0.88 to 8.60). Similarly, a statistically significant association was observed for the unadjusted second tercile of cadmium exposure (OR 1.87, 95% CI 1.06 to 3.30); however, this association was no longer statistically significant after adjustment. None of the other associations tested were statistically significant. Quantile g-computation and BKMR both yielded no significant change of risk of DOR for the mixture of metals, with no evidence of interaction. CONCLUSIONS: Weak signals that some heavy metals could be associated with DOR were detected. These findings should be replicated in other studies

Prospective multicenter observational real-world study to assess the use, efficacy and safety profile of follitropin delta during IVF/ICSI procedures (DELTA Study)

International audienceObjective: To describe the use, efficacy and safety profile of follitropin delta in women undergoing IVF/ICSI in routine clinical practice after one treatment cycle.Study design: This was a French multicenter, prospective, observational study conducted in 14 fertility centers between June 2020 and June 2021. During this period, 248 women undergoing IVF or ICSI were treated with follitropin delta for the first time. Women were followed up to 10-11 weeks after the first fresh or frozen embryo transfer. The main outcomes were use of dosing algorithm, follitropin delta dosing patterns, ovarian response, pregnancy, and adverse drug reactions in routine clinical practice.Results: The analyzable population consisted of 223 patients with mean ± SD age of 33.0 ± 4.4 years, body weight of 65.7 ± 11.8 kg, and the median (IQR) AMH level was 2.6 (1.5-4.0) ng/mL. For 193 patients (86.5 %) it was the first IVF/ICSI cycle and for 30 (13.5 %) the second. The algorithm was used for the calculation of the starting dose for 88.3 % of the patients. The mean daily starting dose of follitropin delta was 11.4 ± 4.1mcg for the whole analyzable population and 14.4 ± 5.2 mcg for the sub-group of 26 patients dosed without the algorithm. The mean duration of stimulation with follitropin delta was 10.8 ± 5.2 days. The mean total dose of follitropin delta administered was 122.2 ± 80.0 mcg. An antagonist protocol was used in 90.3 % of patients. The mean ± SD number of oocytes retrieved among patients that started stimulation was 11.3 ± 6.8 and 46.1 % of patients achieved the targeted response of the algorithm of 8-14 oocytes retrieved. A fresh transfer was performed for 77.6 % of patients; the mean ± SD number of embryos transferred was 1.3 ± 0.5. The implantation rate was 36.0 %. Per started cycle, clinical pregnancy was reported in 35.0 % of the patients and ongoing pregnancy in 29.6 %. In total, 5 patients (2.2 %) reported an event of OHSS.Conclusion: Clinical results as collected in routine clinical practice are promising, showing a favorable effectiveness-safety profile of follitropin delta for a very varied patient population (including anovulatory PCOS, very poor responders, or non-IVF naïve patients). These real-world data complement results from clinical trials and provide useful information for usual clinical practice within a heterogeneous population group