Objectives: To evaluate the feasibility and effectiveness of a postpartum lifestyle intervention after pregnancies complicated by preeclampsia, fetal growth restriction (FGR) and/or gestational diabetes mellitus (GDM) to improve maternal risk factors for future cardiometabolic disease. Methods: Women following a complicated pregnancy were included six months postpartum in this specific pre-post controlled designed study. It has been conducted in one tertiary and three secondary care hospitals (intervention group) and one secondary care hospital (control group). The program consisted of a computer-tailored health education program combined with three individual counselling sessions during seven months. Primary outcome measures were the proportion of eligible women and weight change during the intervention. Results: Two hundred and six women were willing to participate. The proportion of eligible women who complied with the intervention was 23%. Major barrier was lack of time. Adjusted weight change attributed to lifestyle intervention was −1.9 kg (95%-CI −4.3 to −0.3). Further changes were BMI (-0.9 kg/m 2 (95%-CI −1.4 to −0.3)), waist-to-hip ratio (−0.04 cm/cm (95%-CI −0.06 to −0.03)), blood pressure medication use (19% (95%-CI 9% to 28%)), HOMA2-score (59 %S (95%-CI 18 to 99)) and total fat intake (−2.9 gr (95%-CI −4.6 to −1.2)). Conclusions: The results support feasibility and effectiveness of a lifestyle intervention after complicated pregnancies to improve maternal cardiometabolic risk factors. Further randomized controlled studies are needed with longer follow-up to evaluate durability. In the meantime, we suggest health care professionals to offer lifestyle interventions to women after complicated pregnancies.