Association of early-preterm birth with abnormal levels of routinely collected first- and second-trimester biomarkers

Am J Obstet Gynecol. 2013 Jun;208(6):492.e1-11. doi: 10.1016/j.ajog.2013.02.012. Epub 2013 Feb 24.

Abstract

Objective: The purpose of this study was to examine the relationship between typically measured prenatal screening biomarkers and early-preterm birth in euploid pregnancies.

Study design: The study included 345 early-preterm cases (<30 weeks of gestation) and 1725 control subjects who were drawn from a population-based sample of California pregnancies who had both first- and second-trimester screening results. Logistic regression analyses were used to compare patterns of biomarkers in cases and control subjects and to develop predictive models. Replicability of the biomarker early-preterm relationships that was revealed by the models was evaluated by examination of the frequency and associated adjusted relative risks (RRs) for early-preterm birth and for preterm birth in general (<37 weeks of gestation) in pregnancies with identified abnormal markers compared with pregnancies without these markers in a subsequent independent California cohort of screened pregnancies (n = 76,588).

Results: The final model for early-preterm birth included first-trimester pregnancy-associated plasma protein A in the ≤5th percentile, second-trimester alpha-fetoprotein in the ≥95th percentile, and second-trimester inhibin in the ≥95th percentile (odds ratios, 2.3-3.6). In general, pregnancies in the subsequent cohort with a biomarker pattern that were found to be associated with early-preterm delivery in the first sample were at an increased risk for early-preterm birth and preterm birth in general (<37 weeks of gestation; adjusted RR, 1.6-27.4). Pregnancies with ≥2 biomarker abnormalities were at particularly increased risk (adjusted RR, 3.6-27.4).

Conclusion: When considered across cohorts and in combination, abnormalities in routinely collected biomarkers reveal predictable risks for early-preterm birth.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Biomarkers / blood
  • California
  • Case-Control Studies
  • Cohort Studies
  • Female
  • Humans
  • Logistic Models
  • Pregnancy
  • Pregnancy Trimester, First*
  • Pregnancy Trimester, Second*
  • Pregnancy-Associated Plasma Protein-A / metabolism*
  • Premature Birth / blood*
  • Prenatal Diagnosis
  • Risk
  • Young Adult
  • alpha-Fetoproteins / metabolism*

Substances

  • Biomarkers
  • alpha-Fetoproteins
  • Pregnancy-Associated Plasma Protein-A