Background: To calculate an adjusted maternal weight gain during pregnancy including infant and placental weights to the actual weight gain and secondarily examine its influence on the occurrence of fetal macrosomia.
Methods: The corrected weight gain was calculated as follows: maternal body weight at the last prenatal visit - (pregravid body weight + birth weight + placental weight) in 259 women (65 with type 1 diabetes, 69 with gestational diabetes mellitus, and 125 controls).
Results: Although weight gain was greater in non obese normal glucose tolerant and type 1 diabetic mothers of macrosomic infants, the difference was no longer significant when using corrected maternal weight gain. The correlation between birth weight and maternal weight gain decreased when using this index.
Conclusion: The corrected weight gain is a better estimate of true accretion of maternal weight. Our results suggest that recommendations for weight gain during pregnancy should take this index into account.