Abstract
OBJECTIVE: To estimate pregnancy loss incidence in a contemporary cohort of couples whose lifestyles were measured during sensitive windows of reproduction to identify factors associated with pregnancy loss for the continual refinement of preconception guidance. DESIGN: Prospective cohort with preconception enrollment. SETTING: Sixteen counties in Michigan and Texas. PATIENT(S): Three hundred forty-four couples with a singleton pregnancy followed daily through 7 postconception weeks of gestation. INTERVENTION(S): None. Couples daily recorded use of cigarettes, caffeinated and alcoholic beverages, and multivitamins. Women used fertility monitors for ovulation detection and digital pregnancy tests. Pregnancy loss was denoted by conversion to a negative pregnancy test, onset of menses, or clinical confirmation depending upon gestation. Using proportional hazards regression and accounting for right censoring, we estimated adjusted hazard ratios and 95% confidence intervals (aHR, 95% CI) for couples' lifestyles (cigarette smoking, alcoholic and caffeinated drinks, multivitamins) during three sensitive windows: preconception, early pregnancy, and periconception. MAIN OUTCOME MEASURE(S): Incidence and risk factors for pregnancy loss. RESULT(S): Ninety-eight of 344 (28%) women with a singleton pregnancy experienced an observed pregnancy loss. In the preconception window, loss was associated with female age ≥35 years (1.96, 1.13-3.38) accounting for couples' ages, women's and men's consumption of >2 daily caffeinated beverages (1.74, 1.07-2.81; and 1.73, 1.10-2.72, respectively), and women's vitamin adherence (0.45, 0.25-0.80). The findings were similar for lifestyle during the early pregnancy and periconception windows. CONCLUSION(S): Couples' preconception lifestyle factors were associated with pregnancy loss, although women's multivitamin adherence dramatically reduced risk. The findings support continual refinement and implementation of preconception guidance.