To study the association of prepregnancy body mass index (BMI) and gestational weight gain with child neurodevelopmental outcomes.
We performed a secondary analysis of data from two parallel, multicenter, randomized, double-blind, placebo-controlled thyroxine replacement trials in pregnant women with either hypothyroxinemia or subclinical hypothyroidism who delivered at term. Body mass index was categorized as normal (18.5–24.9), overweight (25.0–29.9), or obese (30 or greater). We also evaluated early (20 weeks of gestation or less), late (greater than 20 weeks of gestation), and total gestational weight gain and categorized gestational weight gain as inadequate, adequate, and excessive per 2009 Institute of Medicine guidelines. Neurodevelopmental outcomes included 5-year Wechsler Preschool and Primary Scale of Intelligence and 3-year Differential Ability Scales-II. Linear and logistic regression analyses were performed and adjusted for maternal age, race–ethnicity, education, insurance status, parity, smoking and alcohol use, thyroid status (subclinical hypothyroidism or hypothyroxinemia), treatment group, gestational age at delivery, and neonatal sex.
Of the 948 women included, 380 (40%), 305 (32%), and 263 (28%) had normal, overweight, and obese prepregnancy BMI, respectively. A total of 106 (11%), 212 (22%), and 630 (66%) of women had inadequate, adequate, and excessive total rates of gestational weight gain, respectively. Maternal differences among the BMI categories included race–ethnicity, education, insurance type, parity, and thyroid status (all P<.01), whereas the gestational weight gain groups only differed by parity (P<.001). In unadjusted analysis, children of obese (93.2±12.8; 88.5±13.3) and overweight (94.1±15.6; 89.6±16.0) women had lower Wechsler Preschool and Primary Scale of Intelligence and Differential Ability Scales-II scores, respectively, than normal-weight women (97.4±15.4; 93.9±16.0; P<.001 for all comparisons); however, in adjusted analysis, there were no differences in neurodevelopmental outcomes by maternal BMI. The association was primarily accounted for by race–ethnicity and education. In unadjusted and adjusted analyses, there were no differences in neurodevelopmental outcomes by adequacy of early, late, or total gestational weight gain.
In women with either subclinical hypothyroidism or hypothyroxinemia, neither prepregnancy BMI nor gestational weight gain was associated with neurodevelopmental outcomes among children born at term in adjusted analyses.
Departments of Obstetrics and Gynecology, Northwestern University, Chicago, Illinois, University of Utah Health Sciences Center, Salt Lake City, Utah, University of Texas–Southwestern, Dallas, Texas, Wayne State University, Detroit, Michigan, Columbia University, New York, New York, University of North Carolina, Chapel Hill, North Carolina, University of Texas Medical Branch, Galveston, Texas, University of Alabama at Birmingham, Birmingham, Alabama, Brown University, Providence, Rhode Island, University of Texas–Houston, Houston, Texas, The Ohio State University, Columbus, Ohio, Case Western Reserve University, Cleveland, Ohio, Oregon Health Sciences University, Portland, Oregon, and University of Pittsburgh, Pittsburgh, Pennsylvania; the George Washington University Biostatistics Coordinating Center, Washington, DC; and the Eunice Kennedy Shriver National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network, Bethesda, Maryland.
Corresponding author: Michelle A. Kominiarek, MD, MS, Northwestern University, 250 East Superior Street, Suite 05-2175, Chicago, IL 60611; email: firstname.lastname@example.org.
Supported by grants (HD34116, HD40512, HD27917, HD34208, HD40485, HD40560, HD53097, HD27869, HD40500, HD40545, HD27915, HD40544, HD53118, HD21410, and HD36801) from the Eunice Kennedy Shriver National Institute of Child Health and Human Development and the National Institute of Neurological Disorders and Stroke and the National Center for Advancing Translational Sciences (UL1TR001070). The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.
Financial Disclosure Dr. Wapner serves as Principal Investigator for several studies for which CUMC receives grants. Current funding from commercial entities includes support from Natera Inc, Sequenom, and Illumina, Inc. All funds go directly to CUMC. Dr. Wapner does not receive compensation from any of these grants. He has also received consulting fees from Bioreference, Illumina Inc, and Natera Inc. The other authors did not report any potential conflicts of interest.
* Other members of the NICHD MFMU are listed in Appendix 1, available online at http://links.lww.com/AOG/B199.
The authors thank Lisa Moseley, RN, BSN, and Gail Mallet, RN, BSN, CCRC, for protocol development and coordination between clinical research centers; Barbara Jones-Binns, JD, MPH, for protocol and data management, overall coordination, and quality control; and Elizabeth A. Thom, PhD, Alan M. Peaceman, MD, Michael W. Varner, MD, Deborah G. Hirtz, MD, and Catherine Y. Spong, MD, for protocol development and oversight.
Dr. Rouse, Associate Editor of Obstetrics & Gynecology, was not involved in the review or decision to publish this article.
Each author has indicated that he or she has met the journal's requirements for authorship.
Peer review history is available at http://links.lww.com/AOG/B200.
Presented as a poster at the 2018 Society for Maternal-Fetal Medicine's Annual Pregnancy Meeting, January 29–February 3, 2018, Dallas, Texas.
Received July 18, 2018
Received in revised form September 06, 2018
Accepted September 17, 2018