Early growth is associated with childhood adiposity, but the influence of lifestyle remains unknown. This work aimed to investigate the association of growth profiles from high-risk pregnancies with adiposity at age 5 years, taking into account lifestyle and several antenatal/postnatal exposures. This prospective cohort study. 609 children born during the Finnish Gestational Diabetes Prevention Study (RADIEL), recruiting women with body mass index (BMI) greater than or equal to 30 and/or prior gestational diabetes mellitus (GDM) (2008-2013). Altogether 332 children attended the 5-year follow-up (2014-2017). Main outcome measures included growth profiles based on ponderal index (PI = weight/height3), investigated using latent class mixed models. Adiposity was assessed with anthropometrics and body composition (InBody720). We identified 3 growth profiles: ascending (n = 82), intermediate (n = 351), and descending (n = 149). Children with ascending growth had a higher body fat percentage, ISO-BMI, and waist circumference (P < .05) at age 5 years. Ascending (β 4.09; CI, 1.60-6.58) and intermediate (β 2.27; CI, 0.50-4.03) profiles were associated with higher fat percentage, even after adjustment for age, sex, gestational age, diet, physical activity, education, and prepregnancy BMI. Similar associations existed with ISO-BMI. After adjusting for age and education, ascending growth was associated with prepregnancy BMI (odds ratio [OR] 1.06; CI, 1.01-1.12), primiparity (OR 3.07; CI, 1.68-5.62), cesarean delivery (OR 2.23; CI, 1.18-4.21), and lifestyle intervention (OR 2.56; CI, 1.44-4.57). However, meeting the intervention goals and exclusive breastfeeding for 3 months or more were associated with lower odds of ascending growth. Accelerated early growth was associated with higher adiposity in 5-year-old children from high-risk pregnancies, even when adjusted for lifestyle. Reducing cesarean deliveries and promoting breastfeeding may be beneficial for postnatal growth.