TY - JOUR
T1 - Prepregnancy body mass index and risk of preterm birth
T2 - Association heterogeneity by preterm subgroups
AU - Parker, Margaret G.
AU - Ouyang, Fengxiu
AU - Pearson, Colleen
AU - Gillman, Matthew W.
AU - Belfort, Mandy B.
AU - Hong, Xiumei
AU - Wang, Guoying
AU - Heffner, Linda
AU - Zuckerman, Barry
AU - Wang, Xiaobin
N1 - Funding Information:
The study is supported in part by the March of Dimes PERI grants (PI: Wang, 20-FY02-56), the NIEHS (PI: Wang, R21 ES011666), and the NICHD (PI: Wang, R01 HD041702, R21HD066471). Dr. Fengxiu Ouyang is also supported by grant No. 81102139 from National Natural Science Foundation of China and by the Shanghai Pujiang Program.
PY - 2014/4/30
Y1 - 2014/4/30
N2 - Background: To evaluate the association between prepregnancy body mass index (BMI) is associated with early vs. late and medically-induced vs. spontaneous preterm birth (PTB) subtypes.Methods: Using data from the Boston Birth Cohort, we examined associations of prepregnancy BMI with 189 early (<34 completed weeks) and 277 late (34-36 completed weeks) medically-induced PTBs and 320 early and 610 late spontaneous PTBs vs. 3281 term births (37-44 weeks) in multinomial regression. To assess for mediation by important pregnancy complications, we performed sequential models with and without hypertensive disorders of pregnancy, chorioamnionitis, and gestational diabetes.Results: Prevalence of prepregnancy obesity (BMI ≥ 30.0 kg/m2) was 28% among mothers with medically-induced PTBs, 18% among mothers with spontaneous PTBs, and 18% among mothers with term births (p = <0.001). After adjustment for demographic and known risk factors for PTB, prepregnancy obesity was associated with higher odds of both early [OR 1.78 (1.19, 2.66)] and late [OR 1.49 (1.09, 2.04)] medically-induced PTB. These effect estimates were attenuated with inclusion of hypertensive disorders of pregnancy and gestational diabetes. For spontaneous deliveries, prepregnancy obesity was associated with decreased odds of PTB (0.76 [0.58, 0.98]) and underweight was nearly associated with increased odds of PTB (1.46 [0.99, 2.16]).Conclusion: Prepregnancy obesity is associated with higher risk of medically-induced, but not spontaneous PTB. Hypertensive disorders of pregnancy and gestational diabetes appear to partially explain the association between prepregnancy obesity and early and late medically-induced PTB.
AB - Background: To evaluate the association between prepregnancy body mass index (BMI) is associated with early vs. late and medically-induced vs. spontaneous preterm birth (PTB) subtypes.Methods: Using data from the Boston Birth Cohort, we examined associations of prepregnancy BMI with 189 early (<34 completed weeks) and 277 late (34-36 completed weeks) medically-induced PTBs and 320 early and 610 late spontaneous PTBs vs. 3281 term births (37-44 weeks) in multinomial regression. To assess for mediation by important pregnancy complications, we performed sequential models with and without hypertensive disorders of pregnancy, chorioamnionitis, and gestational diabetes.Results: Prevalence of prepregnancy obesity (BMI ≥ 30.0 kg/m2) was 28% among mothers with medically-induced PTBs, 18% among mothers with spontaneous PTBs, and 18% among mothers with term births (p = <0.001). After adjustment for demographic and known risk factors for PTB, prepregnancy obesity was associated with higher odds of both early [OR 1.78 (1.19, 2.66)] and late [OR 1.49 (1.09, 2.04)] medically-induced PTB. These effect estimates were attenuated with inclusion of hypertensive disorders of pregnancy and gestational diabetes. For spontaneous deliveries, prepregnancy obesity was associated with decreased odds of PTB (0.76 [0.58, 0.98]) and underweight was nearly associated with increased odds of PTB (1.46 [0.99, 2.16]).Conclusion: Prepregnancy obesity is associated with higher risk of medically-induced, but not spontaneous PTB. Hypertensive disorders of pregnancy and gestational diabetes appear to partially explain the association between prepregnancy obesity and early and late medically-induced PTB.
KW - Late preterm birth
KW - Maternal obesity
KW - Medically-induced preterm birth
KW - Prepregnancy BMI
KW - Spontaneous preterm birth
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U2 - 10.1186/1471-2393-14-153
DO - 10.1186/1471-2393-14-153
M3 - Article
C2 - 24779674
AN - SCOPUS:84900499625
SN - 1471-2393
VL - 14
JO - BMC pregnancy and childbirth
JF - BMC pregnancy and childbirth
IS - 1
M1 - 153
ER -