Maternal overweight and obesity during pregnancy associated with increased risk of preterm delivery
In a study that included more than 1.5 million deliveries in Sweden, maternal overweight and obesity during pregnancy were associated with increased risk for preterm delivery, with the highest risks observed for extremely preterm deliveries, according to a study in the June 12 issue of JAMA.
"Maternal overweight and obesity has, due to the high prevalence and associated risks, replaced smoking as the most important preventable risk factor for adverse pregnancy outcomes in many countries. Preterm birth, defined as a delivery of a liveborn infant before 37 gestational weeks, is the leading cause of infant mortality, neonatal morbidity, and long-term disability among non-malformed infants, and these risks increase with decreasing gestational age," according to background information in the article.
Sven Cnattingius, M.D., Ph.D., of the Karolinska Institutet, Stockholm, Sweden, and colleagues conducted a study to examine the associations between early pregnancy body mass index (BMI) and risk of preterm delivery by gestational age and by precursors of preterm delivery. The study included women with live single births in Sweden from 1992 through 2010. Maternal and pregnancy characteristics were obtained from the nationwide Swedish Medical Birth Register. The primary measured outcomes for the study were the risks of preterm deliveries (extremely, 22-27 weeks; very, 28-31 weeks; and moderately, 32-36 weeks). These outcomes were further characterized as spontaneous (related to preterm contractions or preterm premature rupture of membranes) and medically indicated preterm delivery (cesarean delivery before onset of labor or induced onset of labor).
BMI was calculated from information on height and weight at the first prenatal visit. BMI was used to characterize the women as underweight (BMI END
"Maternal overweight and obesity has, due to the high prevalence and associated risks, replaced smoking as the most important preventable risk factor for adverse pregnancy outcomes in many countries. Preterm birth, defined as a delivery of a liveborn infant before 37 gestational weeks, is the leading cause of infant mortality, neonatal morbidity, and long-term disability among non-malformed infants, and these risks increase with decreasing gestational age," according to background information in the article.
Sven Cnattingius, M.D., Ph.D., of the Karolinska Institutet, Stockholm, Sweden, and colleagues conducted a study to examine the associations between early pregnancy body mass index (BMI) and risk of preterm delivery by gestational age and by precursors of preterm delivery. The study included women with live single births in Sweden from 1992 through 2010. Maternal and pregnancy characteristics were obtained from the nationwide Swedish Medical Birth Register. The primary measured outcomes for the study were the risks of preterm deliveries (extremely, 22-27 weeks; very, 28-31 weeks; and moderately, 32-36 weeks). These outcomes were further characterized as spontaneous (related to preterm contractions or preterm premature rupture of membranes) and medically indicated preterm delivery (cesarean delivery before onset of labor or induced onset of labor).
BMI was calculated from information on height and weight at the first prenatal visit. BMI was used to characterize the women as underweight (BMI END