Association among Maternal Obesity, Cervical Length, and Preterm Birth. Am J Perinatol 2017 Apr;34(5):471-479
Date
10/06/2016Pubmed ID
27704492Pubmed Central ID
PMC7189342DOI
10.1055/s-0036-1593350Scopus ID
2-s2.0-84990203091 (requires institutional sign-in at Scopus site) 18 CitationsAbstract
Objective The objective of this study was to determine if mid-trimester cervical length is associated with the inverse relationship between maternal body mass index (BMI) at delivery and spontaneous preterm birth (SPTB). Materials and Methods This was a retrospective cohort of women with a singleton pregnancy without prior SPTB who underwent routine transvaginal cervical length assessment between 18 and 24 weeks. Women were categorized into four BMI groups: (1) 18.5 to 24.9, (2) 25 to 29.9, (3) 30 to 34.9, and (4) ≥ 35 kg/m2. Univariable and multivariable analyses were conducted to determine whether BMI group was associated with SPTB at < 37, 34, or 32 weeks independent of the cervical length. Results Of the 18,100 women in this analysis, 43.5% had a BMI ≥ 30. In univariable analysis, increasing BMI group was associated with longer cervical length but not with cervical length < 10th percentile. SPTB at < 37, 35, and 32 weeks was less common among women with higher BMI. In multivariable regression, a higher BMI group was associated with a lower frequency of SPTB at 37 weeks (adjusted odds ratios [aORs] of 0.64, 0.68, and 0.51), at 34 weeks (aORs of 0.53, 0.54, and 0.31) and at 32 weeks (aORs of 0.47, 0.60, and 0.27) for BMI groups 2 to 4, respectively. This association persisted even when cervical length was entered into the model as a covariate. Conclusion Women with a higher BMI group had longer mid-trimester cervical length, and correspondingly reduced SPTB. However, the decreased risk of SPTB was not associated with cervical length. The reason for the potential protective effect from prematurity is unknown and its mechanisms require further investigation.
Author List
Palatnik A, Miller ES, Son M, Kominiarek MAAuthor
Anna Palatnik MD Associate Professor in the Obstetrics and Gynecology department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AdultBody Mass Index
Cervical Length Measurement
Female
Gestational Age
Humans
Incidence
Obesity
Pregnancy
Pregnancy Trimester, Second
Premature Birth
Retrospective Studies
Young Adult
