title: Associations of Gestational Weight Gain with Preterm Birth among Underweight and Normal Weight Women.
abstract: Studies report increased risk of preterm birth (PTB) among underweight and normal weight women with low gestational weight gain (GWG). However, most studies examined GWG over gestational periods that differ by term and preterm which may have biased associations because GWG rate changes over the course of pregnancy. Furthermore, few studies have specifically examined the amount and pattern of GWG early in pregnancy as a predictor of PTB. Within one integrated health care delivery system, we examined 12,526 singleton pregnancies between 2000 and 2008 among women with a body mass index <25 kg/m(2), who began prenatal care in the first trimester and delivered a live-birth >28 weeks gestation. Using self-reported pregravid weight and serial measured antenatal weights, we estimated GWG and the area under the GWG curve (AUC; an index of pattern of GWG) during the first and second trimesters of pregnancy (≤28 weeks). Using logistic regression adjusted for covariates, we examined associations between each GWG measure, categorized into quartiles, and PTB (<37 weeks gestation). We additionally examined associations according to the reason for PTB by developing a novel algorithm using diagnoses and procedure codes. Low GWG in the first and second trimesters was not associated with PTB [aOR 1.11, (95% CI 0.90, 1.38) with GWG <8.2 kg by 28 weeks compared to pregnancies with GWG >12.9]. Similarly, pattern of GWG was not associated with PTB. Our findings do not support an association between GWG in the first and second trimester and PTB among underweight and normal weight women.
authors: Division of Reproductive Health, National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention, 4770 Buford Hwy NE, MS F-74, Atlanta, GA, 30341, USA, AJSharma@cdc.gov.
authors: Andrea J
authors: AJ
authors: Sharma
authors: Kimberly K
authors: KK
authors: Vesco
authors: Joanna
authors: J
authors: Bulkley
authors: William M
authors: WM
authors: Callaghan
authors: F Carol
authors: FC
authors: Bruce
authors: Jenny
authors: J
authors: Staab
authors: Mark C
authors: MC
authors: Hornbrook
authors: Cynthia J
authors: CJ
authors: Berg
mesh_terms: D000293:Adolescent; D000328:Adult; D015992:Body Mass Index; D001835:Body Weight; D015331:Cohort Studies; D005260:Female; D006801:Humans; D011247:Pregnancy; D047928:Premature Birth; D012189:Retrospective Studies; D012307:Risk Factors; D013851:Thinness / Q000150:complications*; D015430:Weight Gain
references: BMJ. 1990 Jan 27;300(6719):230-5
references: 2106931
references: Obstet Gynecol. 1995 Jun;85(6):909-14
references: 7770259
references: J Nutr. 1996 Jan;126(1):146-53
references: 8558295
references: Paediatr Perinat Epidemiol. 1997 Oct;11(4):392-406
references: 9373862
references: Health Serv Res. 2007 Apr;42(2):908-27
references: 17362224
references: Obstet Gynecol. 2000 Aug;96(2):194-200
references: 10908762
references: Acta Obstet Gynecol Scand. 2008;87(5):510-7
references: 18446533
references: Evid Rep Technol Assess (Full Rep). 2008 May;(168):1-223
references: 18620471
references: Acta Obstet Gynecol Scand. 2011 Sep;90(9):935-54
references: 21623738
references: Paediatr Perinat Epidemiol. 2012 Mar;26(2):109-16
references: 22324496
references: Psychosom Med. 2007 Sep-Oct;69(7):651-9
references: 17766693