Abstract
INTRODUCTION: The objective of this study was to evaluate the association between caffeine and alcohol consumption and in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) outcomes. MATERIAL AND METHODS: The protocol was registered in the PROSPERO database on May 23, 2021 (registration number: CRD42021256649), and updated on August 4, 2022. Two researchers performed a literature search in the PubMed, Embase, and MEDLINE databases for articles published before July 15, 2022 independently. Studies investigating the association between caffeine and alcohol consumption and IVF/ICSI outcomes were included, and studies reporting the consumption amount were analyzed using a one-stage robust error meta-regression-based method to explore potential dose-response relation. Funnel plot was used to assess publication bias if more than 10 studies were included. RESULTS: Twelve studies on caffeine consumption and 14 studies on alcohol consumption were included in the systematic review, of which seven and nine were eligible for the meta-analysis. These studies included 26 922 women and/or their spouses who underwent IVF/ICSI treatment. Women's and men's caffeine consumption was not significantly associated with the pregnancy rate (odds ratio [OR] 0.97, 95% confidence interval [CI] 0.85-1.12; OR 0.93, 95% CI 0.75-1.14; respectively) and the live birth rate (OR 0.98, 95% CI 0.89-1.08; OR 0.98, 95% CI 0.86-1.12; respectively) of IVF/ICSI. Maternal alcohol consumption was negatively associated with pregnancy after IVF/ICSI treatment (OR 0.83, 95% CI 0.69-1.01). Paternal alcohol consumption was negatively associated with partner's live birth after IVF/ICSI treatment (OR 0.88, 95% CI 0.79-0.99). Compared with abstainers, the chance of achieving a pregnancy after IVF/ICSI treatment decreased by 7% for women who consumed 84 g alcohol per week (OR 0.93, 95% CI 0.90-0.98), and the chance of partners achieving a live birth decreased by 9% for men who consumed 84 g alcohol per week (OR 0.91, 95% CI 0.88-0.94). CONCLUSIONS: There was no association between caffeine consumption and pregnancy or live birth rate of IVF/ICSI. Women's alcohol consumption was associated with decreased pregnancy rate after IVF/ICSI treatment when weekly consumption was greater than 84 g. Men's alcohol consumption was associated with decreased live birth rate after IVF/ICSI treatment when weekly consumption was greater than 84 g.