Maternal coffee consumption during pregnancy and risk of childhood acute leukemia: a metaanalysis.

OBJECTIVE: This study was undertaken to explore the association between maternal coffee consumption during pregnancy and childhood acute leukemia (AL). STUDY DESIGN: The PubMed database was used to search studies up to May 5, 2013, and the lists of references of retrieved articles were also screened to identify additional relevant studies. Studies were included if they reported the odds ratio and corresponding 95% confidence interval (CI) of childhood AL, including childhood acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML), with respect to maternal coffee consumption during pregnancy. RESULTS: Compared with non/lowest drinkers, the combined odds ratio regarding the relationship of maternal coffee consumption during pregnancy and childhood AL was 1.22 (95% CI, 1.04-1.43) for ever drinkers, 1.16 (95% CI, 1.00-1.34) for low to moderate-level drinkers, and 1.72 (95% CI, 1.37-2.16) for high-level drinkers. When analysis was conducted by subtypes of childhood AL, maternal coffee consumption (high-level drinkers vs non/lowest drinkers) was statistically significantly associated with childhood ALL (1.65; 95% CI, 1.28-2.12) and childhood AML (1.58; 95% CI, 1.20-2.08). We observed the linear dose-response relationship of coffee consumption and childhood AL (P for nonlinearity = .68), including childhood ALL and childhood AML; with increased coffee consumption, the risk of childhood AL increased. CONCLUSION: The findings of the metaanalysis suggest that maternal coffee consumption during pregnancy may increase the risk of childhood AL. Because of limited studies, further prospective studies are urgently needed to explore the adverse effect of coffee consumption on childhood AL.