Unfavourable intrauterine environment contributes to abnormal gut microbiome and metabolome in twins.

OBJECTIVE: Fetal growth restriction (FGR) is a devastating pregnancy complication that increases the risk of perinatal mortality and morbidity. This study aims to determine the combined and relative effects of genetic and intrauterine environments on neonatal microbial communities and to explore selective FGR-induced gut microbiota disruption, metabolic profile disturbances and possible outcomes. DESIGN: We profiled and compared the gut microbial colonisation of 150 pairs of twin neonates who were classified into four groups based on their chorionicity and discordance of fetal birth weight. Gut microbiota dysbiosis and faecal metabolic alterations were determined by 16S ribosomal RNA and metagenomic sequencing and metabolomics, and the long-term effects were explored by surveys of physical and neurocognitive development conducted after 2~3 years of follow-up. RESULTS: Adverse intrauterine environmental factors related to selective FGR dominate genetics in their effects of elevating bacterial diversity and altering the composition of early-life gut microbiota, and this effect is positively related to the severity of selective FGR in twins. The influence of genetic factors on gut microbes diminishes in the context of selective FGR. Gut microbiota dysbiosis in twin neonates with selective FGR and faecal metabolic alterations features decreased abundances of Enterococcus and Acinetobacter and downregulated methionine and cysteine levels. Correlation analysis indicates that the faecal cysteine level in early life is positively correlated with the physical and neurocognitive development of infants. CONCLUSION: Dysbiotic microbiota profiles and pronounced metabolic alterations are associated with selective FGR affected by adverse intrauterine environments, emphasising the possible effects of dysbiosis on long-term neurobehavioural development.

Body mass index and basal androstenedione are independent risk factors for miscarriage in polycystic ovary syndrome.

BACKGROUND: There is limited literature investigating the effects of body mass index (BMI) and androgen level on in vitro fertilization (IVF) outcomes with a gonadotropin-releasing hormone (GnRH)-antagonist protocol in polycystic ovary syndrome (PCOS). Androgen-related variation in the effect of body mass index (BMI) on IVF outcomes remains unknown. METHODS: In this retrospective study, 583 infertile women with PCOS who underwent IVF using the conventional GnRH-antagonist protocol were included. Patients were divided into four groups according to BMI and androgen level: overweight- hyperandrogenism(HA) group, n = 96, overweight-non-HA group, n = 117, non-overweight-HA group, n = 152, and non-overweight-non-HA group, n = 218. RESULTS: A significantly higher number of oocytes were retrieved, and the total Gn consumption as well Gn consumption per day was significantly lower, in the non-overweight groups than in the overweight groups. The number of available embryos was significantly higher in the HA groups than in the non-HA groups. Clinical pregnancy rate was of no significant difference among four groups. Live-birth rates in the overweight groups were significantly lower than those in non-overweight-non-HA group (23.9, 28.4% vs. 42.5%, P<0.05). The miscarriage rate in overweight-HA group was significantly higher than that in non-overweight-non-HA group (45.2% vs. 14.5%, P<0.05). Multivariate logistic regression analysis revealed that BMI and basal androstenedione (AND) both acted as significantly influent factors on miscarriage rate. The area under the curve (AUC) in receiver operating characteristic (ROC) analysis for BMI and basal AND on miscarriage rate were 0.607 (P = 0.029) and 0.657 (P = 0.001), respectively, and the cut-off values of BMI and basal AND were 25.335 kg/m2 and 10.95 nmol/L, respectively. CONCLUSIONS: In IVF cycles with GnRH-antagonist protocol, economic benefits were seen in non-overweight patients with PCOS, with less Gn cost and more retrieved oocytes. BMI and basal AND were both significantly influential factors with moderate predictive ability on the miscarriage rate. The predictive value of basal AND on miscarriage was slightly stronger than BMI.

Low aneuploidy rate in early pregnancy loss abortuses from patients with polycystic ovary syndrome.

A prospective cohort study was conducted to determine whether chromosome aneuploidy increases the risk of early spontaneous abortions in patients with polycystic ovary syndrome (PCOS). A total of 1461 patients who conceived after IVF and embryo transfer were followed; 100 patients who had experienced clinical spontaneous abortion were recruited, 32 with PCOS and 68 without PCOS. Before 2013, genetic analysis comprised conventional cultured villus chromosome karyotyping and a multiplex ligation-dependent probe amplification subtelomere assay combined with fluorescence in-situ hybridization; since 2013, array-based comparative genomic hybridization technique combined with chromosome karyotyping has been used. Age, BMI, pregnancy history, gestational age and total gonadotrophin dosage did not differ significantly between the PCOS and non-PCOS groups. In the PCOS group, 28.1% of abortuses demonstrated aneuploidy, which was significantly lower (P = 0.001) than in the non-PCOS group (72.1%). Further statistical analyses controlling for maternal age demonstrated that abortuses of women with PCOS were significantly less (P = 0.001) likely to have chromosome aneuploidy. Embryonic aneuploidy does not play a vital role in early spontaneous abortion in women with PCOS. Maternal factors resulting in endometrial disorders are more likely to be responsible for the increased risk of early spontaneous abortion in patients with PCOS.