Women with greater preeclampsia risk also have higher preterm spontaneous birth risk

Key takeaways:

• Pregnancy duration decreased with climbing preeclampsia risk in the first trimester.
• Women at high vs. low preeclampsia risk had a 41% increased risk for spontaneous birth throughout pregnancy.

Spontaneous preterm birth risk throughout pregnancy is higher for women with greater risk for preeclampsia in the first trimester, according to study results published in the American Journal of Obstetrics and Gynecology.

“Prediction of gestational age at spontaneous birth is challenging, particularly when attempted in the first trimester,” Paolo I. Cavoretto, MD, an OB/GYN in the department of obstetrics and gynecology at IRCC San Raffaele Scientific Institute and the Vita-Salute San Raffaele University, Milan, and colleagues wrote. “Moreover, optimal or expected timing of delivery according to the risk of preeclampsia and placental dysfunction was not explored before extensively, and individualization of optimal time for delivery is one of the targets to address with future research to improve maternal-fetal outcomes.”

Cavoretto and colleagues conducted a secondary analysis of data from SPREE, a multicenter cohort investigation that assessed the effectiveness of preterm preeclampsia screening using the Fetal Medicine Foundation model compared with risk scoring recommended by the National Institute for Health and Care Excellence (NICE). This analysis used data from 10,820 cases from SPREE with delivery after spontaneous labor onset. Researchers compared the performance of first-trimester preterm preeclampsia screening by the Fetal Medicine Foundation model with a traditional history-based risk scoring system. All women were categorized into groups based on their risk for preterm preeclampsia at 11 to 13 weeks gestation with 9,795 women in the low-risk group, 1,583 in the intermediate-risk group and 442 in the high-risk group.

In the low-, intermediate- and high-risk groups, 0.29%, 0.69% and 0.45% of women gave birth at less than 28 weeks gestation; 0.64%, 1.71% and 1.81% gave birth at less than 32 weeks; 1.68%, 3.26% and 5.66% gave birth at less than 35 weeks; 4.52%, 7.72% and 13.8% gave birth at less than 37 weeks; and 44.97%, 55.23% and 63.12% gave birth at less than 40 weeks, respectively.

The curve profile for gestational age at spontaneous birth was different overall and in pairwise comparisons for all risk groups (P < .001), the researchers wrote.

Compared with women at low risk for preeclampsia, women at intermediate and high risk had an 18% and 41% increased risk for spontaneous birth, respectively (P < .001 for both).

“Future large-scale studies for big data mining would untangle the controversies on this research area, if centers involved adopt the rigorous research and clinical standard promoted by the Fetal Medicine Foundation,” the researchers wrote. “Research tailored to specific clinical phenotypes of preterm birth related to clinical or subclinical placental dysfunction, may deliver specific interventions fitting with preterm birth etiology.”