What is the chance of having a child following one complete IVF cycle for patients using a freeze-all strategy? The chance of having a child after the first complete IVF cycle was 50.74% with the freeze-all strategy. Several studies have reported on live birth rates (LBRs) based on only the fresh embryo transfer cycle or fresh and frozen–thawed embryo transfer cycles. However, the LBR using a freeze-all strategy in IVF is unknown. This retrospective cohort study included 20 687 women who started their first IVF cycles using a freeze-all strategy during the period from 1 January 2007, through 31 March 2016, in China. Data on 20 687 women undergoing their first complete cycles using a freeze-all strategy from 2007 to 2016 were analyzed to estimate LBRs. The LBR in a complete cycle was defined as the chance of a live birth from an ovarian stimulation cycle including all subsequent frozen embryo transfers from this stimulation. The relationship between LBR and number of oocyte was explored. The LBR for the first complete cycle was 50.74% for patients using a freeze-all strategy. By age group, the LBR declined from 63.81% for women under 31 years old to 4.71% for women over 40 years old after the first complete cycle. The LBRs improved as the number of oocytes retrieved increased up to 25 in the freeze-all strategy. This was a retrospective study without a control group. Data on BMI and smoking status were not collected in this database. Our results showed that 50.74% of patients could achieve a live birth after the first complete cycle via a freeze-all strategy. In addition, the LBRs were positively correlated with the number of oocytes retrieved via the freeze-all strategy. These findings are critical for patients and clinicians in making an informed decision to embark on IVF treatment. This work was supported by grants from the National Natural Science Foundation of China (NSFC) (31770989 to Y.W.) and the Shanghai Ninth People’s Hospital Foundation of China (JYLJ030 to Y.W.). None of the authors have any conflicts of interest to declare.

Objective: Progestin was recently used as an alternative of gonadotropin-releasing hormone (GnRH) analog for preventing premature luteinizing hormone (LH) surge with the aid of vitrification techniques, however, limited data were available about the potential of progestin in poor responders undergoing in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) treatment. We performed a randomized parallel controlled trial to investigate the difference of progestin and GnRH antagonist in poor responders. Methods: A total of 340 poor responders who met with Bologna criteria were randomly allocated into the progestin-primed ovarian stimulation (PPOS) group and GnRH antagonist group. Fresh embryo transfer was preferred in the GnRH antagonist group and freeze-all was performed in the PPOS group. The primary outcome was the incidence of premature LH surge, secondary outcomes were the number of retrieved oocytes, the number of viable embryos and the pregnancy outcomes. Results: The results showed that the incidence of premature LH surge in PPOS group was lower than that in antagonist group (0 vs. 5.88%, P < 0.05). In PPOS group, the average numbers of oocytes and viable embryos were comparable to those in GnRH antagonist group (3.7 ± 2.6 vs. 3.4 ± 2.4; 1.6 ± 1.7 vs. 1.4 ± 1.3, P > 0.05), the live birth rate was similar between the two groups (21.8 vs. 18.2%, RR 1.25 (95% confidence interval 0.73, 2.13), P > 0.05). Conclusions: The study demonstrated that PPOS had a more robust control for preventing premature LH rise than GnRH antagonist in poor responders, but PPOS in combination with freeze-all did not significantly increase the probability of pregnancy than GnRH antagonist protocol for poor responders.

The use of progestin (P) during ovarian stimulation is effective in blocking the luteinizing hormone (LH) surge in women with normal ovarian reserve, however, its effects have not been determined in poor responders. This study aimed to explore the follicular dynamics in P-primed minimal stimulation in poor responders. A total of 204 infertile women with diminished ovarian reserve were allocated into the medroxyprogesterone acetate (MPA) group or the natural-cycle control group in an alternating order. MPA (10 mg) was administered daily beginning from the early follicular phase and a low dose of hMG was added in the late follicular phase if the serum FSH level was lower than 8.0mIU/ml. When a dominant follicle reached maturity, triptorelin 100 μg and hCG 1000 IU were used for trigger, and oocytes were retrieved 34-36 h later.All viable embryos were cryopreserved for subsequent frozen embryo transfer. Natural cycle IVF was used as controls. Compared with the natural cycle group, the MPA group exhibited a larger pre-ovulatory follicle (18.7 ± 1.8 mm vs 17.2 ± 2.2 mm), a longer follicular phase (13.6 ± 3.6 days vs 12.3 ± 3.2 days), and higher peak oestradiol values (403.88 ± 167.16 vs 265.26 ± 122.16 pg/ml), while maintaining lower LH values (P < 0.05). The incidences of spontaneous LH surge and premature ovulation decreased significantly (1.0% vs 50%; 2% vs. 10.8%, respectively; P < 0.05). A greater number of oocytes and viable embryos were harvested from the MPA group than from the natural cycle group (P < 0.05). Moreover,the clinical pregnancy rate was slightly higher in the MPA group than in the natural cycle controls, but the difference was not significant (11.8% vs 5.9%, P > 0.05). This study supported the hypothesis that P-primed minimal stimulation achieved ovulation control of the dominant follicle and did not adversely affect the quality of oocytes in poor responders. Therefore, P-priming is a promising approach to overcome premature ovulation in minimal stimulation for poor responders. ChiCTR-OCH-14004176 . Registered on January 8, 2014.

Is transferring embryos that achieve blastulation on Day 7 effective and safe? Embryos that achieve blastulation on Day 7 resulted in clinically relevant rates of clinical pregnancy (32.5%) and live birth (25.2%), and newborns have a similar risk of low birth weight, congenital malformations or early neonatal death compared with those derived from Days 5 and 6 blastocysts. Potential advantages of blastocyst transfer over cleavage embryo transfer have led to a shift toward the former in IVF practice. However, published data about the fertility outcomes of transferring embryos with a delayed blastulation on Day 7 are scarce and controversial. Moreover, there are few data available on the neonatal outcomes of Day 7 blastocysts. As a result, the clinical value of Day 7 blastocysts is uncertain. This was a retrospective cohort study that included 2908 women undergoing frozen–thawed embryo transfer cycles of IVF/ICSI from January 2006 to May 2015, and reported on the 1518 live born infants from those cycles. We used propensity score matching to compare the fertility outcomes of women undergoing Day-5, Day-6 and Day-7 vitrified embryo transfers in three matched comparisons (Day 5 vs Day 6, Day 5 vs Day 7 and Day 6 vs Day 7). We also compared neonatal outcomes among babies derived from Day-5, Day-6 and Day-7 vitrified embryo transfers. We studied 922 Day-5, 1752 Day-6 and 234 Day-7 vitrified embryo transfers. Day-7 vitrified embryo transfers had significantly lower implantation, clinical pregnancy and live birth rates than both Day-5 (23.9 vs 49.9%, 31.7 vs 58.1% and 25.1 vs 46.5%, all P < 0.001, respectively) and Day-6 (24.7 vs 42.3%, 33.0 vs 53.2% and 25.6 vs 41.4%, all P < 0.001, respectively) vitrified embryo transfers. Assessment of babies showed no statistically significant difference in the rates of low birth weight, congenital malformations and early neonatal death among the 585, 869 and 64 babies born from Day-5, Day-6 and Day-7 vitrified embryo transfer groups, respectively. This was a single center retrospective study, and most of the neonatal data were extracted from parental questionnaires. Besides, the number of Day-7 vitrified embryo transfer cycles and babies born from these cycles was still limited, thus reducing the power of our study in assessing neonatal outcomes. In addition, only the morphologically poorer Day 3 embryos were extendedly cultured, and poorer blastocysts were qualified for vitrification on Day 7 than on Day 5 or 6, both of which might bias clinical pregnancy rates. Transfer of embryos that reach the blastocyst stage on Day 7 results in lower but still acceptable live birth rate, and seems to be safe for the offspring. Extension of the culture time in embryos that do not reach blastocyst stage by Day 6 should be assessed in randomized clinical trials. This work was supported by the National Nature Science Foundation of China (Grant nos. 81771533, 81571397, 81571486, 31770989 and 81501319), the Nature Science Foundation of Shanghai (Grant nos. 15ZR1424900 and 1441196300), and the Foundation of Health and Family Planning Commission of Shanghai (Grant no. 201540237). B.W.M is supported by the National Health and Medical Research Council (NHMRC) Practitioner Fellowship (GNT1082548), B.W.M reports consultancy for ObsEva, Merck and Guerbet. Not applicable.

Polycystic ovary syndrome (PCOS) is an endocrinopathy with complex pathophysiology that is a common cause of anovulatory infertility in women. Although the disruption of circadian rhythms is indicated in PCOS, the role of the clock in the etiology of these pathologies has yet to be appreciated. The nuclear receptors REV-ERBα and REV-ERBβ are core modulators of the circadian clock and participate in the regulation of a diverse set of biological functions. However, in PCOS, the expression of REV-ERBs and their effects remain unclear. Here, we demonstrate that the levels of REV-ERBα and REV-ERBβ expression were lower in the granulosa cells of PCOS patients than in control subjects. In vitro, we found that the overexpression of REV-ERBα and REV-ERBβ, and their agonist SR9009, promoted the expression of mitochondrial biosynthesis genes PGC-1α, NRF1, and TFAM and inhibited autophagy in KGN cells. Our results also indicate that REV-ERBα and REV-ERBβ can inhibit apoptosis in granulosa cells and promote proliferation. Importantly, the REV-ERB agonist SR9009 ameliorates abnormal follicular development by promoting mitochondrial biosynthesis and inhibiting autophagy in a mouse PCOS model. This allows us to speculate that SR9009 has potential as a therapeutic agent for the treatment of PCOS.