Rescue in vitro maturation may increase the pregnancy outcomes among women undergoing intracytoplasmic sperm injection.

Introduction: To investigate whether rescue in vitro maturation (R-IVM) improves the reproductive outcomes among women undergoing intracytoplasmic sperm injection (ICSI) after one oocyte retrieved cycle. Methods: Between January 2019 and December 2020, 2602 women who underwent ICSI in the Reproductive Medicine Center of Tongji Hospital, Wuhan, China, were included in our retrospective cohort study. There were 2112 women undergoing only ICSI and 490 women with R-IVM followed by ICSI. The intermediate reproductive outcomes and pregnancy outcomes were assessed, including the number of normally fertilized embryos, number of cleaved embryos, number of good-quality embryos, number of day-3 available embryos, number of embryos cultured past day-3, number of blastocysts, number of available blastocysts, biochemical pregnancy, miscarriage, clinical pregnancy and live birth. The perinatal outcomes were also assessed, including preterm birth and birth weight. The abovementioned outcomes were also calculated for in vivo matured and R-IVM oocytes separately in women undergoing ICSI with R-IVM group. Results: Compared with the women who underwent only ICSI, those who underwent ICSI with R-IVM had higher numbers of MII oocytes, normally fertilized embryos, cleaved embryos, day-3 available embryos, embryos cultured past day-3, and higher oocyte maturation rate, available embryo rate than women undergoing only ICSI. Additionally, we found that women undergoing ICSI with R-IVM had an increased chance of clinical pregnancy (adjusted OR=1.50, 95% CI: 1.17-1.93) and cumulative live birth (adjusted OR=1.35, 95% CI: 1.07-1.71). After propensity score matching (PSM), the cumulative live birth rate was 60.1% for women undergoing ICSI with R-IVM versus 54.9% for women undergoing only ICSI (OR=1.24, 95% CI: 0.94-1.63). The reproductive outcomes were also significantly different when calculated for in vivo matured and R-IVM oocytes separately in women undergoing ICSI with R-IVM group. All live births from R-IVM embryos were healthy and without malformations or complications. Conclusion: R-IVM may improve the reproductive outcomes of women undergoing ICSI. It may also provide a reference for the safety of R-IVM. This study maybe support a routine application of R-IVM among patients who intend to undergo ICSI.

Associations of sleep characteristics with outcomes of IVF/ICSI treatment: a prospective cohort study.

STUDY QUESTION: Are sleep characteristics associated with outcomes of IVF/ICSI treatment? SUMMARY ANSWER: Nocturnal sleep <7 h/night and disturbed sleep are related to impaired oocyte and embryo yield, while longer nocturnal sleep might reduce the chance of a successful pregnancy, and the associations between nocturnal sleep duration and IVF/ICSI outcomes are modified by maternal age and subjective sleep quality. WHAT IS KNOWN ALREADY: Disturbed sleep and circadian rhythm contribute to impaired fecundity in the general population, but the effects of sleep characteristics on IVF/ICSI outcomes are largely unknown. STUDY DESIGN, SIZE, DURATION: This study was conducted among 1276 women undergoing IVF/ICSI treatment between December 2018 and September 2019 based on the Tongji Reproductive and Environmental cohort. Owing to the limited number of multiple cycles, we included only the outcomes of their first IVF/ICSI cycle in the current analysis. PARTICIPANTS/MATERIALS, SETTING, METHODS: Data on sleep characteristics were collected via questionnaires on the day of oocyte retrieval. IVF/ICSI outcomes were abstracted from medical records. Quasi-Poisson, quasi-binomial or logistic regression models were used to assess the relations between sleep characteristics and reproductive outcomes after adjusting for relevant confounders. We also performed stratified analyses by subjective sleep quality (good versus poor) and maternal age (≤30 versus >30 years). MAIN RESULTS AND THE ROLE OF CHANCE: Compared with women who slept 7 to <8 h/night, those who slept <7 h/night exhibited decreases in the number of retrieved and mature oocytes of 11.5% (95% CI: -21.3%, -0.48%) and 11.9% (95% CI: -22.4%, -0.03%), respectively. A mid-sleep time (MST) earlier than 2:21 a.m. (<2:21 a.m.) or later than 3:00 a.m. (≥3:00 a.m.) and poor subjective sleep quality were inversely associated with the fertilization rate. Women who had trouble falling asleep more than three times per week had a lower number of mature oocytes (-10.5%, 95% CI: -18.6%, -1.6%), normal fertilized oocytes (-14.8%, 95% CI: -23.7%, -4.8%) and good-quality embryos (-15.1%, 95% CI: -25.4%, -3.5%) than those who had no such trouble. In addition, women who slept 9 to <10 h/night had a lower chance of clinical pregnancy compared to women who slept 7 to <8 h/night (odds ratio = 0.65, 95% CI: 0.44, 0.98). In the stratified analyses, the positive associations of nocturnal sleep duration with the number of good-quality embryos and fertilization rate existed only among the women with poor subjective sleep quality (P for interaction = 0.02 and 0.03, respectively). Additionally, we found that the positive associations of nocturnal sleep duration with implantation or clinical pregnancy only existed among women aged over 30 years (P for interaction = 0.04 and 0.01, respectively). LIMITATIONS, REASONS FOR CAUTION: Sleep characteristics are self-reported, which may lead to misclassification. MST serves as a proxy of chronotype and may be non-differentially misclassified resulting in an underestimate of the association of interest. Measuring sleep characteristics on the day of oocyte retrieval may lead to bias. Chance findings cannot be excluded because of the limited number of women with <7 h or ≥10 h nocturnal sleep and multiple testing. Our results may be biased by other confounders and may not be generalizable to women of other ethnicities. WIDER IMPLICATIONS OF THE FINDINGS: Unhealthy sleep characteristics, including short nocturnal sleep, inappropriate sleep time, poor subjective sleep quality and having trouble falling asleep, may impair oocyte quantity and its potential to mature or be fertilized. Long nocturnal sleep might reduce the chance of clinical pregnancy among infertile females, especially women younger than 30 years old. Prolonged nocturnal sleep duration may be a potential beneficial behavior for improving IVF/ICSI outcomes for women aged over 30 years and women with poor subjective sleep quality, which requires further investigation. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by the National Natural Science Foundation of China (81771654) and the National Key R&D Program of China (No. 2018YFC1004201). There are no conflicts of interest to declare. TRIAL REGISTRATION NUMBER: N/A.

Associations between drinking water disinfection byproducts and menstrual cycle characteristics: A cross-sectional study among women attending an infertility clinic.

Disinfection byproducts (DBPs) have been shown to alter ovarian steroidogenesis and cause estrous cyclicity disturbance and prolongation in experimental studies, however human studies are lacking. We aimed to evaluate the cross-sectional associations between drinking water DBPs and menstrual cycle characteristics. A total of 1078 women attending an infertility clinic in Wuhan, China were included between December 2018 and January 2020. Characteristics of menstrual cycle were collected by questionnaires. Concentrations of dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA) were measured in urine as biomarkers of drinking water DBPs. Multivariate logistic and linear regression models were used to evaluate the associations between urinary DCAA and TCAA concentrations and menstrual cycle characteristics. Higher urinary DCAA concentrations were associated with increased odds ratios (ORs) of irregular menstrual cycle (OR = 1.80; 95% CI: 0.97, 3.33 for the highest vs. lowest quartile; P for trend = 0.05) and long menstrual cycle (OR = 1.62; 95% CI: 0.97, 2.70 for the highest vs. lowest quartile; P for trend = 0.06), as well as prolonged variation in cycle length (ß = 1.27 days; 95% CI: -0.11, 2.66 for the highest vs. lowest quartile; P for trend = 0.04). Higher urinary TCAA concentrations were associated with prolonged bleeding duration (ß = 0.23 days; 95% CI: -0.06, 0.51 for the highest vs. lowest quartile; P for trend = 0.07). These results suggest that exposure to drinking water DBPs is associated with menstrual cycle disturbances. These findings are warranted to confirm in other studies.

Ovarian Toxicity and Epigenetic Mechanisms of Phthalates and Their Metabolites.

Ovary plays an important role in the female reproductive system. The maintenance and regulation of ovarian function are affected by various physical and chemical factors. With the development of industrialization, environmental pollutants have caused great harm to public health. Phthalates, as a class of endocrine-disrupting chemicals (EDCs), are synthesized and used in large quantities as plasticizers due to their chemical properties. They are easily released into environment because of their noncovalent interactions with substances, causing human exposure and possibly impairing ovary. In recent years, more and more attention has been paid to the role of epigenetics in the occurrence and development of diseases. And it is urgent to study the role of methylation, gene imprinting, miRNA, and other epigenetic mechanisms in reproductive toxicology.