Objective: To investigate the effects of body mass index (BMI) on assisted reproductive outcomes with the freeze-all strategy for patients with polycystic ovary syndrome (PCOS). Design: Retrospective cohort study. Setting: Tertiary care academic medical center. Patient(s): A total of 3,079 women with PCOS across different BMIs at our institution from January 2015 to May 2017 were stratified into cohorts. Intervention(s): None. Main Outcome Measure(s): Implantation rate, clinical pregnancy rate, early miscarriage rate, and live birth rate. Result(s): The live birth rate was most favorable in underweight (BMI < 18.5 kg/m 2 ) and normal weight cohorts (18.5 % BMI < 25 kg/ m 2 ) and progressively decreased as BMI increased. Moreover, the obese cohort (BMI R 30 kg/m 2 ) of patients with PCOS who had frozen ET cycles had a relatively high early miscarriage rate. Conclusion(s):The live birth rates are highest in underweight and normal weight patients with PCOS undergoing IVF with the freeze-all strategy. Furthermore, there is a progressive and statistically significant decrease in the live birth rate and an increase in the miscarriage rate in obese patients with PCOS. (Fertil Steril Ò 2019;112:1172-9. Ó2019 by American Society for Reproductive Medicine.) El resumen está disponible en Español al final del artículo.

Purpose: To investigate whether progestin-primed ovarian stimulation (PPOS) can be an alternative as gonadotrophin-releasing hormone agonist (GnRHa) long protocol for infertile women with normal ovarian reserve during IVF/ICSI. Methods: A prospective randomized controlled trial (RCT) including 257 patients was conducted between 1 August 2017 to 1 January 2018. Computerized randomization was performed to assign participants into two treatment groups at a 1:1 ratio: PPOS (130 patients) or GnRHa long protocol (127 patients) followed by their first IVF/ICSI with fresh/frozen embryo transfer. The primary outcome was the number of oocytes retrieved. Patients with normal ovarian reserve undergoing their first IVF/ICSI procedure were included. The embryological and clinical outcomes were measured. Only the first embryo transfer cycle was followed-up. Results: Basic characteristics such as infertility duration, age, and body mass index (BMI) were comparable in both groups. No significant difference was found in the number (mean ± SD) oocytes retrieved [11.8 ± 6.5 for PPOS vs 11.3 ± 5.6 for GnRHa long protocol] or viable embryos [4.5 ± 3.0 for PPOS vs 4.2 ± 2.9 for GnRHa long protocol] between the groups. No patient from either group experienced a premature LH surge during the whole process of ovarian stimulation. Besides, there was no moderate or severe ovarian hyperstimulation syndrome during the ovarian stimulation in PPOS group while three patients suffered it in the GnRHa long protocol group. There was no significant difference in the clinical pregnancy rate of the first embryos transfer cycle between the two groups. Conclusion: PPOS in combination with embryo cryopreservation as an ovarian stimulation regimen was as effective as GnRHa long protocol during controlled ovarian stimulation (COH) under different endocrinal mechanisms. It can also achieve comparable embryological and clinical outcomes while reducing the incidence of moderate and severe ovarian hyperstimulation syndrome (OHSS) and HMG dosage. It can be an alternative of the treatments for infertile patients with normal ovarian reserve undergoing IVF as well as traditional protocols.

Background: Endometrial preparation is essential in frozen-thawed embryo transfer (FET) cycles. Recent studies suggested that different endometrial preparation methods may influence obstetrical complications. However, the association between hormone replacement therapy (HRT) and ovarian stimulation (OS) FET endometrial preparation and obstetrical complications remains unknown.Methods: This retrospective cohort study included a total of 79,662 confirmed embryo transfer cycles during the period from January 2003 to December 2019. After exclusion, the remaining cases were categorized into an ovarian stimulation FET group (OS FET group, n = 29,121) and a hormone replacement therapy FET group (HRT FET group, n = 26,776) and subjected to the analyses. The primary outcome was the rate of obstetrical complications included placenta previa, placenta abruption, hypertensive disorders of pregnancy (HDP), placenta accreta, gestational diabetes mellitus (GDM), preterm premature rupture of the membrane (pPROM). The secondary outcome was pregnancy outcomes such as live birth rate, birth weight, pre-term and post-term delivery and cesarean sections. In order to minimize the bias, 10 pregnancy-related factors were adjusted in multiple logistic regression analysis.Results: Placenta previa (0.6 vs. 1.2%, P &lt; 0.001) and HDP (3.5 vs. 5.3%, P &lt; 0.001) were found lower in the OS FET than HRT FET group. Cesarean section was observed lower in the OS than HRT group (76.3 vs. 84.3%, P &lt; 0.001). After adjustment for 10 important pregnancy-related confounding factors, we found that the risk of placenta previa (aOR 0.54, 95% CI 0.39–0.73) and HDP (aOR 0.65, 95% CI 0.57–0.75) and cesarean section (aOR 0.61, 95% CI 0.57–0.66) were still significantly reduced in the OS than HRT group. Furthermore, live birth rates were higher (80.0 vs. 76.0%, P &lt; 0.001), and the miscarriage rate was lower (17.7 vs. 21.3%, P &lt; 0.001) for pregnancies conceived with OS FET than with HRT FET. And the average birth weight was lower in the OS group compared to HRT group (2982.3 ± 636.4 vs. 3025.0 ± 659.0, P &lt; 0.001), as well as the small-for-gestational age (SGA) was higher (8.7 vs. 7.2%, P &lt; 0.001) and the large-for-gestational age (LGA) was lower (7.2 vs. 8.6%, P &lt; 0.001) in the OS group than in the HRT group.Conclusions: The risks of placenta previa and HDP were lower in patients conceiving after OS FET than in those after HRT FET. Further prospective studies are required to further clarify the mechanism underlying the association between endometrium preparation and obstetrical complications.