Gestational Weight Gain and Perinatal Outcomes in Adolescent Mothers: A Retrospective Cohort Study

Optimal gestational weight gain (GWG) may differ for adolescents since they themselves may continue to grow throughout pregnancy. We examined the associations between GWG and perinatal outcomes among adolescents aged < 20 years and determined whether they differed from the associations among adult women aged 20 to 35 years.

We conducted a retrospective cohort study of live born, singleton deliveries to 3725 adolescents and 50 400 adult women in Nova Scotia between 2003 and 2014. GWG was categorized as below, within, or above the 2009 Institute of Medicine recommendations. Primary outcomes were preterm birth (< 37 weeks), small for gestational age (SGA; < 10(th) percentile), large for gestational age (LGA; > 90th percentile), and delivery by Caesarean section. Adjusted odds ratios (OR) with 95% confidence intervals (CI) were estimated from logistic regression models.

Adolescent mothers with GWG above the recommendations (relative to mothers who gained within the recommendations) had higher odds of having an LGA neonate (OR 2.20; 95% CI 1.62 to 2.99) and having a Caesarean section (OR 1.33; 95% CI 1.07 to 1.64), but lower odds of having an SGA neonate (OR 0.65; 95% CI 0.51 to 0.84). Adolescent mothers with low GWG had decreased odds of having an LGA neonate (OR 0.58; 95% CI 0.34 to 0.98) and increased odds of having an SGA neonate (OR 1.72; 95% CI 1.30 to 2.27).

Among adolescents, GWG was significantly associated with several perinatal outcomes. More research considering other outcomes is needed to determine the optimal GWG for adolescent women.