Preconception alcohol consumption and risk of miscarriage in over 4.5 million Chinese women aged 20-49 years.

OBJECTIVE

To assess the impact of preconception alcohol consumption on risk of miscarriage incidence, and further evaluate the association between maternal periconception drinking abstinence and miscarriage.

METHODS

We performed a population-based, retrospective cohort study in China between 1 January 2013 and 31 December 2016. Alcohol intake and potential confounding factors were reported in standard questionnaires. Participants who became pregnant were recontacted for pregnancy outcome information within 1 year. A total 4 531 680 women with available data on preconception alcohol intake and miscarriage were included in the final analyses. Multivariable logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (95% CIs).

RESULTS

The prevalence of miscarriage was 2.70% among 4 531 680 women. Compared with non-drinkers, the adjusted OR of miscarriage was 1.06 (95% CI 1.02 to 1.10) and 1.59 (95% CI 1.15 to 2.20) in maternal occasional drinkers and regular drinkers, respectively. Compared with couples in which neither the male nor the female consumed alcohol, the adjusted OR for miscarriage among women was 1.09 (95% CI 1.07 to 1.10), 1.13 (95% CI 1.06 to 1.21) and 1.12 (95% CI 1.07 to 1.17) in the couples in which only the female drank alcohol, only the male drank alcohol, and both drank alcohol, respectively. The adjusted OR was 0.58 (95% CI 0.51 to 0.65) in women with alcohol abstinence compared with alcohol drinkers.

CONCLUSIONS

Preconception alcohol consumption was associated with higher odds of miscarriage, and an increasing risk was found with paternal and maternal alcohol drinking. Periconception alcohol abstinence was inversely associated with miscarriage.