Caffeine and miscarriage risk.
BACKGROUND
Coffee and caffeine have been inconsistently found to be associated with increased risk of clinical miscarriage-a potentially important association given the high prevalence of exposure.


METHODS
Women were recruited before or early in pregnancy and interviewed regarding sources of caffeine, including assessment of changes over the perinatal period. We identified 2407 clinically-recognized pregnancies resulting in 258 pregnancy losses. We examined the relationship of coffee and caffeine intake with clinically-recognized pregnancy loss prior to 20 weeks' completed gestation, using a discrete-time continuation ratio logistic survival model.


RESULTS
Coffee and caffeine consumption at all 3 time points were unrelated to total miscarriage risk and the risk of loss after the interview. Reported exposure at the time of the interview was associated with increased risk among those with losses before the interview.


CONCLUSIONS
There is little indication of possible harmful effects of caffeine on miscarriage risk within the range of coffee and caffeine consumption reported, with a suggested reporting bias among women with losses before the interview. The results may reflect exposure misclassification and unmeasured heterogeneity of pregnancy losses.
Savitz
David A
DA
Department of Community and Preventive Medicine, Mount Sinai School of Medicine, New York, New York 10029, USA. david.savitz@mssm.edu
Chan
Ronna L
RL
Herring
Amy H
AH
Howards
Penelope P
PP
Hartmann
Katherine E
KE
D000022:Abortion, Spontaneous / Q000453:epidemiology*; D000293:Adolescent; D000328:Adult; D002110:Caffeine / Q000009:adverse effects*; D003069:Coffee / Q000009:adverse effects*; D005260:Female; D006801:Humans; D007407:Interviews as Topic; D008875:Middle Aged; D009657:North Carolina / Q000453:epidemiology; D009749:Nutrition Surveys; D016017:Odds Ratio; D011247:Pregnancy; D012307:Risk Factors; D013714:Tennessee / Q000453:epidemiology; D013781:Texas / Q000453:epidemiology
D003069:Coffee; D002110:Caffeine