Intake of probiotic food and risk of spontaneous preterm delivery.

BACKGROUND Preterm delivery represents a substantial problem in perinatal medicine worldwide. Current knowledge on potential influences of probiotics in food on pregnancy complications caused by microbes is limited. OBJECTIVE We hypothesized that intake of food with probiotics might reduce pregnancy complications caused by pathogenic microorganisms and, through this, reduce the risk of spontaneous preterm delivery. DESIGN This study was performed in the Norwegian Mother and Child Cohort on the basis of answers to a food-frequency questionnaire. We studied intake of milk-based products containing probiotic lactobacilli and spontaneous preterm delivery by using a prospective cohort study design (n = 950 cases and 17,938 controls) for the pregnancy outcome of spontaneous preterm delivery (< 37 gestational weeks). Analyses were adjusted for the covariates of parity, maternal educational level, and physical activity. RESULTS Pregnancies that resulted in spontaneous preterm delivery were associated with any intake of milk-based probiotic products in an adjusted model [odds ratio (OR): 0.857; 95% CI: 0.741, 0.992]. By categorizing intake into none, low, and high intakes of the milk-based probiotic products, a significant association was observed for high intake (OR: 0.820; 95% CI: 0.681, 0.986). CONCLUSION Women who reported habitual intake of probiotic dairy products had a reduced risk of spontaneous preterm delivery.