Relation of body mass index to frequency of recurrent preterm birth in women treated with 17-alpha hydroxyprogesterone caproate

Among pregnant women receiving 17OHP-C prophylaxis for a prior preterm birth, recurrent preterm birth before 32 weeks was significantly more common in those women whose prepregnancy BMI was 25 kg/m2 or greater than in women with BMI less than 25 kg/m2. This observation is consistent with pharmacological studies suggesting that dosing regimens of 17OHP-C may affect efficacy.