Objective: The present study evaluated the association between fruit and vegetable intake and the incidence of upper respiratory tract infection (URTI) during pregnancy.
Design: In a cohort of 1034 North American women, each subject was asked retrospectively about their fruit and vegetable intake during the six months before the pregnancy and their occurrences of URTI during the first half of pregnancy. Multivariable-adjusted hazard ratios (HR) were calculated with Cox proportional hazards models.
Results: The adjusted HR of URTI for women in the highest quartile (median 8.54 servings/d) v. the lowest quartile (median 1.91 servings/d) of total fruit and vegetable intake was 0.74 (95 % CI 0.53, 1.05) for the 5-month follow-up period and 0.61 (95 % CI 0.39, 0.97) for the 3-month follow-up period, respectively. A dose-related reduction of URTI risk according to quartile of intake was found in the 3-month (P for trend = 0.03) but not the 5-month follow-up. No association was found between either fruit or vegetable intake alone in relation to the 5-month or the 3-month risk of URTI.
Conclusions: Women who consume more fruits and vegetables have a moderate reduction in risk of URTI during pregnancy, and this benefit appears to be derived from both fruits and vegetables instead of either alone.