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Published on: August 2, 2017
Correlation between spontaneous preterm birth and mid-trimester maternal serum estriol
Richelle N Olsen1, Rebecca Dunsmoor-Su, Daniel Capurro
1Department of Obstetrics and Gynecology, University of Washington , Seattle , USA .
Summary
Elevated second trimester maternal serum estriol is linked to spontaneous preterm birth. Higher estriol levels correlate with earlier delivery, indicating a potential early warning sign for pregnancy complications.
Area of Science:
- Reproductive Endocrinology
- Maternal-Fetal Medicine
- Obstetrics
Background:
- Third trimester salivary estriol is a known predictor of preterm birth.
- The utility of second trimester serum estriol as a predictive marker remains less understood.
Purpose of the Study:
- To investigate the association between second trimester maternal serum estriol concentrations and the risk of preterm delivery.
- To determine if early estriol levels can predict spontaneous preterm birth.
Main Methods:
- Retrospective cohort study of 7767 patients undergoing second trimester aneuploidy screening.
- Measurement of unconjugated serum estriol using immunoassay, reported as multiples of the median (MoM).
- Statistical analysis to evaluate the correlation between estriol MoM and preterm birth (<37 weeks gestation).
Main Results:
- Elevated second trimester estriol (1.15 MoM) was significantly associated with preterm birth compared to term delivery (1.03 MoM), with an odds ratio of 1.69.
- A higher proportion of patients delivering spontaneously before 34 weeks had estriol MoM > 2 (9.95%) versus those delivering after 34 weeks (6.23%).
- A direct correlation was observed between estriol concentration levels and earlier gestational age at delivery.
Conclusions:
- Elevated second trimester maternal serum unconjugated estriol is an independent predictor of spontaneous preterm birth.
- Second trimester estriol levels may serve as an early biomarker for identifying pregnancies at risk for preterm delivery.
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