The rate of delivery at o32 weeks in women with inadequate
gestational weight gain at 20 to 28 weeks was 37.6% (35/93) as compared with
15.2% (60/396) in the group with adequate gestational weight gain (Po0.001).
When analyzed in BMI group, normal weight, overweight and
obese women with inadequate gestational weight gain at 20 to 28 weeks all had
higher rates of preterm delivery at o32 weeks than those with
adequate gestational weight gain (Table 4). The mean gestational age at delivery
for women with adequate gestational weight gain at 20 to 28 weeks was
35.0 ± 3.2 weeks compared with 32.9 ± 4.9 weeks for those with
inadequate gestational weight gain at 20 to 28 weeks (Pฒ0.001). Inadequate gestational weight gain
at 20 to 28 weeks was associated with higher rate of spontaneous
preterm birth at o32 weeks (25.8% (24/93) vs 6.8% (27/396); Po0.001), but
no differences in indicated preterm birth (11.8% (11/93) vs 8.3% (33/396);
P = 0.29).