A pre-conception cohort study of fertility and its related factors among couples with the intention of conception / 中华预防医学杂志

Objective: To describe fertility and explore factors associated with it among pre-conception couples of childbearing age. Methods: Based on the pre-conceptional offspring trajectory study of the School of Public Health of Fudan University, couples of childbearing age who participated in the pre-conception physical examination in Shanghai Jiading District from 2016 to 2021 were recruited and followed up. Couples' time to pregnancy (TTP) was analyzed and Cox proportional hazards regression model was used to explore the factors associated with TTP. Kaplan-Meier was used to calculate each menstrual cycle's cumulative pregnancy rate. Results: A total of 1 095 preconception couples were included in the analysis, the M(Q1,Q3)of TTP was 4.33 (2.41, 9.78) menstrual cycles. Age of women (FR=0.90, 95%CI: 0.85-0.95, P<0.001), women who were overweight or obese before pregnancy (FR=0.36, 95%CI: 0.24-0.55, P<0.001), women who were exposed to second-hand smoking (FR=0.63, 95%CI: 0.44-0.92, P=0.016), women whose home or office had been renovated in the past 2 years and had a particular smell (FR=0.46, 95%CI: 0.26-0.81, P=0.008) were risk factors for impaired fertility. Regular menstrual cycles (FR=1.64, 95%CI: 1.16-2.31, P=0.005), females who often drank tea/coffee (FR=1.55, 95%CI: 1.11-2.17, P=0.011) and males who took folic acid before conception (FR=2.35, 95%CI: 1.38-4.23, P=0.002) were associated with better fertility. The cumulative pregnancy rate of 3, 6, and 12 menstrual cycles was 37.6%, 64.4%, and 78.4%, respectively. Conclusion: Older couples, overweight or obesity before pregnancy, irregular menstruation, exposure to secondhand smoke and decoration pollutants in females are associated with impaired fertility. Frequent tea/coffee drinking before pregnancy in females and taking folic acid before pregnancy in males are associated with shortened conception time.

Study on the levels and risk factors of Vitamin D from preconception to pregnancy / 中华疾病控制杂志

Objective To investigate the levels of serum Vitamin D(VD) from preconception to pregnancy in Jiading district of Shanghai, and explore the risk factors of VD concentration deficiency in the second and third trimester of pregnancy. Methods A total of 94 women who planned to have antenatal care and delivery in Maternal and Child Health Hospital of Jiading district of Shanghai from September 2016 to December 2018 were recruited as the study participants. Chemiluminescent immunoassay (CLIA) was used to examine the concentration of women’s serum VD from preconception to pregnancy. A total of 282 serum samples were detected. Results The prevalence of VD deficiency among 94 women from preconception to pregnancy were 40.4%,57.4% and 48.9% respectively. Results of the mixed linear model showed that women who had dyed or permed hair within the past 1 year had significantly lower serum VD levels during pregnancy (P<0.05), and women who often drank milk and ate deep-sea fish during pregnancy had higher VD levels during pregnancy (P<0.05). Conclusions VD deficiency was common among women in Jiading district of Shanghai, and it should be emphasized to supplement VD before and during pregnancy.