(2016) A modified natural cycle results in higher live birth rate in vitrified-thawed embryo transfer for women with regular menstruation, Systems Biology in Reproductive Medicine, 62:5, 335-342, DOI: 10.1080/19396368.2016 To link to this article: https://doi.org/10. 1080/19396368.2016 There is no consensus regimen for the optimal endometrial preparation for cryopreservation and vitrified-thawed embryo transfer cycles. This is largely caused by the lack of sufficient investigation and analyses on the respective pregnancy and perinatal outcomes by different regimens. This study aimed to compare both pregnancy and perinatal outcomes between the modified natural and artificial cycles in vitrified-thawed day three embryo transfer for women with regular menstruation. A total of 1,482 vitrified-thawed day three embryo transfer cycles were reviewed including 427 modified natural cycles (NC), 132 ovulation induction cycles (OC), 794 artificial cycles (AC), and 129 GnRH agonist artificial cycles (GAC). The primary outcome that was evaluated was live birth rate. The NC regimen demonstrated a higher rate of ongoing pregnancy (43.8% vs. 30.2%, P = 0.002) and a lower rate of late abortion (2.8% vs. 14.0%, P = 0.003) than the GAC regimen as well as a higher implantation rate (31.9% vs. 27.1%, P = 0.008) and live birth rate (43.1% vs. 34.1%, P = 0.002) than the AC regimen. A significantly higher peak endometrial thickness before transfer was observed in patients using the NC and GAC regimens (10.0 ± 1.7, 9.9 ± 2.4) compared to the AC regimens (9.2 ± 1.5, P = 0.000). Multivariate logistic regression showed that the NC protocol was associated with a higher live birth rate. There were no significant differences in rates of pregnancy complications, neonatal mortality, birth defects, mean birth weight, and other perinatal outcomes among the regimens. Modified natural cycle endometrial preparation regimen for vitrified-thawed day three embryo transfer is associated with superior live birth pregnancy outcomes compared to artificial cycles. Future studies are warranted to investigate the underlying biologic mechanisms of these findings.Abbreviations ART: assisted reproductive technology; BMI: body mass index; FET: frozen-thawed embryo transfer; HCG: human chorionic gonadotropin; IVF: in-vitro fertilization; IVF-ET: in-vitro fertilization and embryo transfer; OHSS: ovarian hyperstimulation syndrome; RCTs: randomized controlled trials ARTICLE HISTORY

ObjectiveTo compare the cumulative live birth rate (CLBR) of the progestin-primed ovarian stimulation (PPOS) protocol with that of the flexible GnRH antagonist protocol in patients with poor prognosis diagnosed per the POSEIDON criteria.MethodsThis was a retrospective cohort study. Low-prognosis women who underwent IVF/ICSI at the Reproductive Center of Third Affiliated Hospital of Zhengzhou University between January 2016 and January 2019 were included according to the POSEIDON criteria. The CLBR was the primary outcome of interest. The secondary outcome measures were the numbers of oocytes retrieved, 2PN embryos, available embryos and time to live birth.ResultsA total of 1329 women met the POSEIDON criteria for analysis. For POSEIDON group 1, the dosage of gonadotropin (Gn) was higher in the PPOS group than in the GnRH antagonist group (2757.3 ± 863.1 vs 2419.2 ± 853.1, P=0.01). The CLBR of the PPOS protocols was 54.4%, which was similar to the rate of 53.8% in the GnRH antagonist group. For POSEIDON group 2, the number of available embryos was higher in the PPOS group (2.0 ± 1.7 vs 1.6 ± 1.4, P=0.02) than in the GnRH antagonist group. However, the CLBRs of the two groups were similar (18.1% vs 24.3%, P=0.09). For POSEIDON groups 3 and 4, there were no statistically significant differences in the number of oocytes retrieved, 2PN, available embryos or CLBR between the two protocols. After adjustments for confounding factors, the CLBR remained consistent with the unadjusted rates. In the POSEIDON group 1 population, the GnRH antagonist protocols had a shorter time to live birth (P=0.04).ConclusionFor low-prognosis patients diagnosed per the POSEIDON criteria, the CLBR of PPOS protocols is comparable to that of GnRH antagonist protocols. In the POSEIDON group 1 population, the GnRH antagonist protocols resulted in a shorter time to live birth.

Introduction: To evaluate the effectiveness and safety of long-acting GnRH agonist follicular and GnRH antagonist protocols among women undergoing in vitro fertilization (IVF) using data published in both English-language and Chinese studies. Methods: We systematically searched the PubMed, Embase, Cochrane, CNKI, and Wanfang databases up to March 2019 for studies comparing long-acting GnRH agonist follicular and GnRH antagonist protocols in women undergoing IVF. The primary outcome was live

ObjectiveTo compare the clinical outcomes of dydrogesterone (DYG) and medroxyprogesterone (MPA) in the progestin-primed ovarian stimulation (PPOS) protocol for patients with poor ovarian response (POR).Patients and MethodsThis was a retrospective cohort study. Women with POR who underwent IVF/ICSI at the Reproductive Center of Third Affiliated Hospital of Zhengzhou University between January 2020 and January 2021 were included. The primary outcome measure of our study was the number of oocytes retrieved. The secondary outcome measures in the present study were the number of 2PN, number of available embryos, oocyte retrieval rate, fertilization rate, viable embryo rate per oocyte retrieved, cancellation rate and pregnancy outcomes of the first embryo transfer cycle, including the biochemical pregnancy, clinical pregnancy and miscarriage rates.ResultsIn total, 118 women underwent hMG +DYG protocols, and 692 women who underwent hMG +MPA met the Bologna criteria for POR. After baseline characteristics were balanced using the PSM model, 118 hMG +DYG protocols were matched to 118 hMG +MPA protocols, and the baseline characteristics were comparable between the two groups. The numbers of oocytes retrieved, 2PN, and available embryos and the oocyte retrieval rate, fertilization rate, viable embryo rate per oocyte retrieved and cancellation rate of the hMG+DYG and hMG+MPA protocols were comparable. Altogether, 66 women in the hMG+DYG group and 87 women in the hMG+MPA group underwent first embryo transfers. In the hMG+DYG group, 81.8% (54/66) of the patients underwent cleavage embryo transfers; similarly, 79.3% (69/87) of patients in the hMG+MPA group had cleavage embryo transfers (P=0.70).The biochemical pregnancy rate of the hMG+DYG group was 42.4%, and this was comparable to the rate in the hMG+DYG group, at 34.5% (P=0.32). The clinical pregnancy rates were similar between the two groups (36.4% vs. 31.0%, P=0.49), and there was no significant difference in the rate of miscarriage between the two groups (12.5% vs. 29.6%, P=0.14).ConclusionFor women with POR, the clinical outcome of the hMG + DYG group was similar to that of the hMG + MPA group, indicating that both combinations can be useful options for PPOS protocols.

Background: Successful implantation and delivery require both the functional embryo and receptive endometrium in assisted reproductive technology (ART) cycles. However, little is known about embryo-endometrial interaction on live-birth. We aimed to investigate the independent effect and interaction of endometrial thickness (EMT) and embryo quality on live-birth in fresh embryo transfer (ET) cycles. Methods: We conducted a retrospective cohort study including 15,012 ART cycles between 2013 and 2016 in three centers in China. Poisson regression with generalized estimating equations was employed to calculate relative risks (RRs) and 95% confidence intervals (CIs). We estimated the interaction of embryo quality and EMT on live-birth rate (LBR). Results: The LBR per cycle was 42.8% overall. LBR increased with increasing EMT and reached a plateau (50.6 to 54.2%) when EMT was 11 mm or thicker. Embryo quality represented by cumulative score was associated with LBR independently of number of embryos transferred and EMT. LBR was not increased with thicker EMT when only Q1 cleavage-stage embryo transferred (aRR 0.95, 95%CI 0.61-1.46). LBR was not increased significantly with thicker EMT with transfer of two good-quality cleavage-stage embryos and any blastocyst combination except Q1 group. There was significant interaction between EMT and embryo quality on LBR for cleavage-stage ETs (P=0.023). Conclusions: This study demonstrated the nonlinear EMT-LBR association and the EMT cutoff value of 11 mm which may be of more clinical significance for predicting live-birth. Embryo quality is an independent prognostic tool for LBR. Our finding of significant embryo-endometrial interaction indicates combination of EMT and embryos quality might improve the prognostic value in clinical practice for live-birth in patients undergoing transfer of 1-2 fresh cleavage-stage embryos.