Body composition changes in the postpartum: a systematic review on measurements and predictors

Introduction This systematic review investigated changes in maternal body composition and specific anthropometric indices during the postpartum period, and the factors influencing these changes. Methods Longitudinal observational studies with at least two measurements of postpartum maternal body composition and anthropometry were included. Studies that assessed only BMI or included a single postpartum measurement without a corresponding preconception measure were excluded. Medline/PubMed, Scopus, EMBASE, CINAHL, Web of Science, and ProQuest databases were searched for studies published up to 30th September 2025. Conference proceedings or studies not published in English were excluded. The risk of bias was assessed using the Assessing risk of bias and confounding in observational studies of interventions or exposures tool from the Agency for Healthcare Research and Quality. Data on the changes in body composition and associated factors were summarised and presented in graphical and tabular formats. The review was reported according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. Results Of 1,273 abstracts screened, 86 studies were retained for data extraction. Sixty-one studies assessed changes in body composition and anthropometry, while 44 studies examined the association between various factors and body composition outcomes. Overall, 73 body composition and anthropometric indices were reported, with fat mass ratio/percentage being the most frequently used measure. Waist circumference showed a substantial reduction during the first month of the postpartum. The timing of initial measurements, length of follow-up, and techniques varied widely; 59% of studies concluded follow-up at or before 9 months postpartum. Techniques used to assess body composition ranged from skinfold thickness and circumference measurements to bioelectrical impedance analysis and dual-energy X-ray absorptiometry. Conclusions This systematic review underscores the complexity and variability of postpartum body composition changes. Given the association between postpartum adiposity and adverse long-term maternal health outcomes, integrating body composition and anthropometric assessments alongside BMI is essential. Extending follow-up beyond one year postpartum may further improve understanding and management of postpartum adiposity in clinical practice.