CV events during pregnancy up risk of preterm birth, SGA

Cardiovascular (CV) events during pregnancy appear to moderately increase the risk of adverse pregnancy outcomes (APOs), such as preterm birth, small for gestational age (SGA), or both, reports a recent study.

A California population-based birth cohort (2005‒2010) was used to identify women with CV events, autoimmune rheumatic diseases (ARDs), and primary antiphospholipid syndrome (APS) using the International Classification of Diseases, 9th and 10th revisions, Clinical Modification codes in maternal discharge records.

The authors identified selected APOs from birth certificates, namely preterm birth (<37 weeks’ gestation), SGA infants (birth weight <10th percentile for age and sex), and a composite of either outcome. They then calculated the adjusted risk ratios (ARRs) with 95 percent confidence intervals (CIs) for adverse outcomes.

CV events were more frequent among women with ARDs (265 of 19,340, 1.4 percent) and primary APS (428 of 7,758, 5.5 percent) than those without (17,130 of 7,004,334, 0.3 percent).

Compared with absence, the presence of CV events significantly correlated with a higher incidence of adverse outcomes in ARD (53.2 percent vs 26.6 percent), APS (30.6 percent vs 20.7 percent), and non-ARD/APS pregnancies (28.2 percent vs 15.2 percent).

Moreover, CV events appeared to elevate the risks of SGA in all groups (aRRs, 1.2‒1.5) and preterm birth in ARD (aRR, 1.6, 95 percent CI, 1.3‒2.0) and non-ARD/APS (aRR, 1.7, 95 percent CI, 1.7‒1.8) pregnancies.

“Notably, >50 percent of ARD pregnancies with CV events experienced APOs,” the authors said. “Given that ARD and APS pregnancies have higher (although still low) rates of CVEs and have higher baseline risks of APOs than the general population, the additional burden conferred by CVEs is clinically important.”