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

• Published in: American journal of obstetrics and gynecology Vol. 208; no. 6; pp. 492.e1 - 492.e11
• Main Authors: Jelliffe-Pawlowski, Laura L., Shaw, Gary M., Currier, Robert J., Stevenson, David K., Baer, Rebecca J., O'Brodovich, Hugh M., Gould, Jeffrey B.
• Format: Journal Article
• Language: English
• Published: United States Mosby, Inc 01.06.2013
• Subjects: Adolescent; Adult; alpha-Fetoproteins - metabolism; biomarker; Biomarkers - blood; California; Case-Control Studies; Cohort Studies; Female; Humans; Logistic Models; Obstetrics and Gynecology; Pregnancy; Pregnancy Trimester, First; Pregnancy Trimester, Second; Pregnancy-Associated Plasma Protein-A - metabolism; Premature Birth - blood; Prenatal Diagnosis; prenatal screening; preterm birth; Risk; Young Adult; California; preterm birth; biomarker; prenatal screening
• ISSN: 0002-9378; 1097-6868; 1097-6868
• DOI: 10.1016/j.ajog.2013.02.012

The purpose of this study was to examine the relationship between typically measured prenatal screening biomarkers and early-preterm birth in euploid pregnancies. 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). 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). When considered across cohorts and in combination, abnormalities in routinely collected biomarkers reveal predictable risks for early-preterm birth.