Preconception alcohol consumption in both partners and risk of miscarriage.

RESEARCH QUESTION: Is preconception maternal or paternal alcohol intake associated with risk of miscarriage?

DESIGN

Pregnancy Study Online (PRESTO) is an ongoing web-based prospective cohort study of couples trying to conceive. All primary data collection occurred via self-administered questionnaires. Baseline questionnaires in both partners collected data on sociodemographics, medical history, anthropometrics and lifestyle factors, including preconception alcohol consumption. Female participants reported data on pregnancy outcomes on follow-up questionnaires. Cox proportional hazards regression models were used to estimate hazard ratios and 95% confidence intervals (95% CI) for the association between preconception alcohol consumption in both partners and miscarriage rate.

RESULTS

The study included 9414 female (mean age 30 years) and 2613 male (mean age 32 years) participants. About 27% of the female participants reported no preconception alcohol use, compared with 20% of males. Approximately 20% of pregnancies ended in miscarriage. After adjustment for demographic, lifestyle and reproductive variables, no appreciable association was observed between preconception alcohol intake and miscarriage. In the couples-based analysis of the association of miscarriage with preconception alcohol use, compared with female participants who reported no alcohol intake, the hazard ratios for those reporting 0.1-6.9, 7-13.9 and ≥14 drinks per week were 0.91 (95% CI 0.74-1.13), 1.06 (95% CI 0.77-1.46) and 0.80 (95% CI 0.43-1.52), respectively; for male the hazard ratios were 0.94 (95% CI 0.74-1.19), 0.93 (95% CI 0.70-1.25) and 0.84 (95% CI 0.59-1.19), respectively. Results were consistent across alcohol types (wine, liquor, beer) and within strata of age, history of miscarriage and gestational age.

CONCLUSIONS

Preconception alcohol use in either partner was not associated with higher miscarriage risk.