Interpregnancy BMI change and subsequent pregnancy outcomes
Table 2 shows the adjusted associations of interpregnancy BMI
change status with maternal and neonatal outcomes in the second
pregnancy. Compared to women with a stable BMI from the first to the
second pregnancy, those with BMI loss had a higher risk of low
birthweight delivery (RR 1.36; 95% CI 1.02, 1.80). Women with moderate
BMI gain had higher risks of LGA birth (1.16; 1.03, 1.31), GDM (1.25;
1.06, 1.49) and emergency caesarean delivery (1.16; 1.03, 1.31) in the
second pregnancy; these risks were higher in those with excess BMI gain.
Similar findings were obtained in a sensitivity analysis using crude
interpregnancy BMI change (Table S3 ).
Table 3 shows the adjusted associations of interpregnancy BMI
change status with maternal and neonatal outcomes in the second
pregnancy, stratified by weight status in the first pregnancy. In women
with BMI ≥23 kg/m2, BMI loss was associated with
increased risk of low birthweight (1.64; 1.09, 2.47) and SGA deliveries
(1.54; 1.02, 2.34). In women with BMI <23
kg/m2, moderate (1.31; 1.07, 1.59) and excess BMI
gains (1.35; 1.04, 1.77) were associated with an increased risk of
emergency caesarean.