Objective: To assess birthweight in relation to gestationalweight gain (GWG) among womenwho were andwere
not obese before pregnancy.Methods: For a retrospective cohort study, datawere obtained forwomenwith a prepregnancy
body mass index (BMI, calculated as weight in kilograms divided by the square of height in meters)
of at least 30 who had a singleton delivery at a center in Denmark in 2010–2011. Data were also obtained for
455 non-obesewomen (BMI 20.0–24.9).GWGwas expressed in absolute terms and relative to published recommendations
(11–16 kg in non-obesewomen; 5–9 kg in obese women). Results: A total of 231 obesewomenwere
included in analyses. In non-obese and obesewomen, fetalweightwas highestwhenGWGwas above the recommended
amount. Among women who had a GWG in line with the recommendations, mean birth weight was
higher among those with a pre-pregnancy BMI of 35.0–39.9 (3758 ± 410 g) or at least 40 (3671 ± 374 g)
than among non-obesewomen (3394±453 g; P=0.0058). Conclusion: Birthweight is related to both maternal
BMI and GWG. In obese women, adherence to GWG recommendations does not seem to prevent increased
birth weights.