The association between COVID-19 and infertility: Mendelian randomization analysis.

Since December 2019, COVID-19 has triggered a global pandemic. The association of COVID-19 with the long-term reproductive situation of women and males is not clear. Thus, our aim was to assess the causal association between COVID-19 and infertility using Mendelian randomization (MR) analysis based on the OpenGWAS database. Two-sample MR analysis was conducted using one genome-wide association study (GWAS) on COVID-19 and infertility in individuals of European ancestry. The summary data of genetic variation come from the GWAS in European populations. We applied several MR methods, including MR Egger, weighted median, inverse variance weighted, simple mode, weighted mode, to test causal relationships. After observing the statistical analysis results of MR, we conducted sensitivity analysis to test robustness. After gene prediction, it was found that there was no clear causal relationship between COVID-19 and male infertility in MR analysis [OR 0.4702 (95% CI, 0.1569-1.4093), P = .178]. Moreover, COVID-19 was not associated with female infertility [OR 0.9981 (95% CI, 0.763-1.544), P = .646]. Sensitivity analysis showed that the MR results were robust [level pleiotropy, male: (MR-Egger, intercept = 0.1967434; se = 0.1186876; P = .2392406); female: (MR-Egger, intercept = -0.05902506; se = 0.05362049; P = .3211367)]. To further validate the impact of COVID-19 on infertility, we added a covariate (sex hormone binding global levels, abortion) to the MR analysis, which is a multivariate MR analysis. According to univariate and multivariate MR analyses, the evidence does not support that COVID-19 is a causal risk factor for infertility in European population. This information can provide information for doctors in reproductive centers when managing infertility patients.

Inadequate gestational weight gain and adverse pregnancy outcomes among normal weight women in China.

OBJECTIVE: The objective of the paper is to find the association between inadequate gestational weight gain and pregnancy outcomes in normal weight women in China. METHOD: A retrospective study was conducted among 13,776 normal weight pregnant women who received antenatal care and delivered singleton infants at the participating hospital during August, 2009 to July, 2013. Adverse pregnancy outcomes like low birth weight (LBW), preterm birth, birth asphyxia, neonatal intensive care unit (NICU) admission and length of hospital stay were compared and analyzed between two groups with inadequate and adequate gestational weight gain. RESULTS: According to the IOM recommendations, inadequate gestational weight gain was found to be 14.7% in this study. Women with inadequate gestational weight gain (GWG) were found to be at a higher risk for LBW (aOR = 2.13, 95% CI: 1.75, 2.86) and preterm birth (aOR = 1.44, 95% CI: 1.21, 1.67) than those in the adequate gestational weight gain group, after adjusting for monthly family income, maternal education, occupation, and whether they received any advice regarding benefits of gestational weight gain and residential area. However, inadequate GWG was not associated with longer hospital stay (aOR = 1.13, 95% CI: 0.91-1.43) in adjusted model. In addition, the rate of birth asphyxia and NICU admission were similar in both groups (P > 0.05). CONCLUSIONS: Normal weight pregnant women with GWG below the recommended AIOM 2009 guidelines were found to be at an increased risk of low birth weight and preterm birth.