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Am J Perinatol 2017; 34(05): 471-479
DOI: 10.1055/s-0036-1593350
Original Article
Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Association among Maternal Obesity, Cervical Length, and Preterm Birth

Anna Palatnik
1   Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
,
Emily S. Miller
1   Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
,
Moeun Son
1   Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
,
Michelle A. Kominiarek
1   Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
› Author Affiliations
Further Information

Publication History

01 March 2016

12 August 2016

Publication Date:
23 September 2016 (online)

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Abstract

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.

Keywords

cervical length - body mass index - preterm birth - spontaneous preterm birth

Note

This study was presented in the poster format at the 36th annual meeting of the Society for Maternal-Fetal Medicine, Atlanta, GA, February 1–6, 2016.


 

  • References

  • 1 Hamilton BE, Martin JA, Osterman MJ, Curtin SC, Matthews TJ. Births: Final Data for 2014. Natl Vital Stat Rep 2015; 64 (12) 1-64
    PubMedGoogle Scholar
  • 2 Goldenberg RL, Culhane JF, Iams JD, Romero R. Epidemiology and causes of preterm birth. Lancet 2008; 371 (9606): 75-84
    CrossrefPubMedGoogle Scholar
  • 3 Behrman RE, Butler AS , eds. Preterm Birth: Causes, Consequences, and Prevention. Institute of Medicine (US) Committee on Understanding Premature Birth and Assuring Healthy Outcomes. Washington (DC): National Academies Press (US); 2007
    Google Scholar
  • 4 Russell RB, Green NS, Steiner CA , et al. Cost of hospitalization for preterm and low birth weight infants in the United States. Pediatrics 2007; 120 (1) e1-e9
    CrossrefPubMedGoogle Scholar
  • 5 Committee on Practice Bulletins—Obstetrics, The American College of Obstetricians and Gynecologists. Practice bulletin no. 130: prediction and prevention of preterm birth. Obstet Gynecol 2012; 120 (4) 964-973
    CrossrefPubMedGoogle Scholar
  • 6 Han Z, Mulla S, Beyene J, Liao G, McDonald SD ; Knowledge Synthesis Group. Maternal underweight and the risk of preterm birth and low birth weight: a systematic review and meta-analyses. Int J Epidemiol 2011; 40 (1) 65-101
    CrossrefPubMedGoogle Scholar
  • 7 Sebire NJ, Jolly M, Harris JP , et al. Maternal obesity and pregnancy outcome: a study of 287,213 pregnancies in London. Int J Obes Relat Metab Disord 2001; 25 (8) 1175-1182
    CrossrefPubMedGoogle Scholar
  • 8 Nohr EA, Bech BH, Vaeth M, Rasmussen KM, Henriksen TB, Olsen J. Obesity, gestational weight gain and preterm birth: a study within the Danish National Birth Cohort. Paediatr Perinat Epidemiol 2007; 21 (1) 5-14
    CrossrefPubMedGoogle Scholar
  • 9 Smith GC, Shah I, Pell JP, Crossley JA, Dobbie R. Maternal obesity in early pregnancy and risk of spontaneous and elective preterm deliveries: a retrospective cohort study. Am J Public Health 2007; 97 (1) 157-162
    CrossrefPubMedGoogle Scholar
  • 10 Torloni MR, Betrán AP, Daher S , et al. Maternal BMI and preterm birth: a systematic review of the literature with meta-analysis. J Matern Fetal Neonatal Med 2009; 22 (11) 957-970
    CrossrefPubMedGoogle Scholar
  • 11 McDonald SD, Han Z, Mulla S, Beyene J ; Knowledge Synthesis Group. Overweight and obesity in mothers and risk of preterm birth and low birth weight infants: systematic review and meta-analyses. BMJ 2010; 341: c3428 DOI: 10.1136/bmj.c3428.
    CrossrefPubMedGoogle Scholar
  • 12 Khatibi A, Brantsaeter AL, Sengpiel V , et al. Prepregnancy maternal body mass index and preterm delivery. Am J Obstet Gynecol 2012; 207 (3) 212.e1-212.e7 DOI: 10.1016/j.ajog.2012.06.002.
    CrossrefPubMedGoogle Scholar
  • 13 Cnattingius S, Villamor E, Johansson S , et al. Maternal obesity and risk of preterm delivery. JAMA 2013; 309 (22) 2362-2370
    CrossrefPubMedGoogle Scholar
  • 14 Iams JD, Goldenberg RL, Meis PJ , et al; National Institute of Child Health and Human Development Maternal Fetal Medicine Unit Network. The length of the cervix and the risk of spontaneous premature delivery. N Engl J Med 1996; 334 (9) 567-572
    CrossrefPubMedGoogle Scholar
  • 15 van der Ven AJ, van Os MA, Kleinrouweler CE , et al. Is cervical length associated with maternal characteristics?. Eur J Obstet Gynecol Reprod Biol 2015; 188: 12-16
    CrossrefPubMedGoogle Scholar
  • 16 Hendler I, Goldenberg RL, Mercer BM , et al. The preterm prediction study: association between maternal body mass index and spontaneous and indicated preterm birth. Am J Obstet Gynecol 2005; 192 (3) 882-886
    CrossrefPubMedGoogle Scholar
  • 17 Liabsuetrakul T, Suntharasaj T, Suwanrath C, Leetanaporn R, Rattanaprueksachart R, Tuntiseranee P. Serial translabial sonographic measurement of cervical dimensions between 24 and 34 weeks' gestation in pregnant Thai women. Ultrasound Obstet Gynecol 2002; 20 (2) 168-173
    CrossrefPubMedGoogle Scholar
  • 18 Centers for disease control and prevention. About adult BMI. Available at: https://www.cdc.gov/healthyweight/assessing/bmi/adult_bmi/ . Retrieved July 7, 2016
    PubMedGoogle Scholar
  • 19 Grobman WA, Thom EA, Spong CY , et al; Eunice Kennedy Shriver National Institute of Child Health and Human Development Maternal-Fetal Medicine Units (MFMU) Network. 17 alpha-hydroxyprogesterone caproate to prevent prematurity in nulliparas with cervical length less than 30 mm. Am J Obstet Gynecol 2012; 207 (5) 390.e1-390.e8
    CrossrefPubMedGoogle Scholar
  • 20 Centers for disease control and prevention. Obesity and overweight. Available at: http://www.cdc.gov/nchs/fastats/obesity-overweight.htm . Retrieved July 1, 2015
    PubMedGoogle Scholar
  • 21 ACOG practice bulletin no. 156: obesity and pregnancy. Obstet Gynecol 2015; 126 (6) e112-e126
    CrossrefPubMedGoogle Scholar
  • 22 Ehrenberg HM, Iams JD, Goldenberg RL , et al; Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) Maternal-Fetal Medicine Units Network (MFMU). Maternal obesity, uterine activity, and the risk of spontaneous preterm birth. Obstet Gynecol 2009; 113 (1) 48-52
    CrossrefPubMedGoogle Scholar
  • 23 Stotland NE, Washington AE, Caughey AB. Prepregnancy body mass index and the length of gestation at term. Am J Obstet Gynecol 2007; 197 (4) 378.e1-378.e5
    CrossrefPubMedGoogle Scholar
  • 24 Denison FC, Price J, Graham C, Wild S, Liston WA. Maternal obesity, length of gestation, risk of postdates pregnancy and spontaneous onset of labour at term. BJOG 2008; 115 (6) 720-725
    CrossrefPubMedGoogle Scholar
  • 25 Halloran DR, Cheng YW, Wall TC, Macones GA, Caughey AB. Effect of maternal weight on postterm delivery. J Perinatol 2012; 32 (2) 85-90
    CrossrefPubMedGoogle Scholar
  • 26 Mercer BM, Goldenberg RL, Das A , et al. The preterm prediction study: a clinical risk assessment system. Am J Obstet Gynecol 1996; 174 (6) 1885-1893 , discussion 1893–1895
    CrossrefPubMedGoogle Scholar
  • 27 Smith R, Mesiano S, McGrath S. Hormone trajectories leading to human birth. Regul Pept 2002; 108 (2–3) 159-164
    CrossrefPubMedGoogle Scholar
  • 28 Campbell EA, Linton EA, Wolfe CD, Scraggs PR, Jones MT, Lowry PJ. Plasma corticotropin-releasing hormone concentrations during pregnancy and parturition. J Clin Endocrinol Metab 1987; 64 (5) 1054-1059
    CrossrefPubMedGoogle Scholar
  • 29 Sasaki A, Shinkawa O, Margioris AN , et al. Immunoreactive corticotropin-releasing hormone in human plasma during pregnancy, labor, and delivery. J Clin Endocrinol Metab 1987; 64 (2) 224-229
    CrossrefPubMedGoogle Scholar
  • 30 Strain GW, Zumoff B, Kream J, Strain JJ, Levin J, Fukushima D. Sex difference in the influence of obesity on the 24 hr mean plasma concentration of cortisol. Metabolism 1982; 31 (3) 209-212
    CrossrefPubMedGoogle Scholar
  • 31 Jessop DS, Dallman MF, Fleming D, Lightman SL. Resistance to glucocorticoid feedback in obesity. J Clin Endocrinol Metab 2001; 86 (9) 4109-4114
    CrossrefPubMedGoogle Scholar
  • 32 Li N, Liu E, Guo J , et al. Maternal prepregnancy body mass index and gestational weight gain on offspring overweight in early infancy. PLoS ONE 2013; 8 (10) e77809 DOI: 10.1371/journal.pone.0077809.
    CrossrefPubMedGoogle Scholar
  • 33 Rudra CB, Frederick IO, Williams MA. Pre-pregnancy body mass index and weight gain during pregnancy in relation to preterm delivery subtypes. Acta Obstet Gynecol Scand 2008; 87 (5) 510-517
    CrossrefPubMedGoogle Scholar
  • 34 Dietz PM, Callaghan WM, Cogswell ME, Morrow B, Ferre C, Schieve LA. Combined effects of prepregnancy body mass index and weight gain during pregnancy on the risk of preterm delivery. Epidemiology 2006; 17 (2) 170-177
    CrossrefPubMedGoogle Scholar
  • 35 Masho SW, Bishop DL, Munn M. Pre-pregnancy BMI and weight gain: where is the tipping point for preterm birth?. BMC Pregnancy Childbirth 2013; 13: 120 DOI: 1186/1471-2393-13-120.
    CrossrefPubMedGoogle Scholar