Smoking, alcohol and coffee consumption and pregnancy loss

A mendelian randomization study was conducted to determine the associations of smoking and alcohol and coffee consumption with pregnancy loss.
Data was based on a total of 60,565 cases with pregnancy loss and 130,687 non cases from UK Biobank study and 3,312 cases with pregnancy loss and 64,578 non cases from FinnGen consortium.
The study found that genetic predisposition to smoking initiation was associated with an increased risk of pregnancy loss in both UK Biobank and FinnGen. The combined odds ratio (OR) was 1.31 (95% confidence interval [CI], 1.25-1.37) for one standard deviation increase in the prevalence of smoking initiation. There were no significant associations of genetically predicted consumption of alcohol (OR, 1.09; 95% CI, 0.93-1.27) or coffee (OR, 0.96; 95% CI, 0.87-1.06) with pregnancy loss.
This study on the basis of genetic data suggests the causal potential of the association of smoking but not moderate alcohol and coffee consumption with pregnancy.
Source: Yuan S, Liu J, Larsson SC. Smoking, alcohol and coffee consumption and pregnancy loss: a Mendelian randomization investigation. Fertil Steril. 2021 Oct;116(4):1061-1067.