Quantifying the Burden of Congenital Cytomegalovirus Infection With Long-term Sequelae in Subsequent Pregnancies of Women Seronegative at Their First Pregnancy.

BACKGROUND

In women seronegative before pregnancy, congenital cytomegalovirus (cCMV)-related sequelae are exclusively seen in those infected in the first trimester of pregnancy. Following a maternal primary infection in the first trimester, up to 30% of infected neonates suffer long-term sequelae. Maternal parity is an established risk factor of cCMV in previously seronegative women. Our objective was to quantify, in a population of women seronegative at their first pregnancy, the risk of cCMV and related sequelae following primary infections in the first trimester in subsequent pregnancies.

METHODS

There were 739 women seronegative at their first pregnancy who had at least 1 of 971 subsequent pregnancies and deliveries managed at our institution. All women had CMV immunoglobin (Ig) G and IgM testing at 11-14 weeks of each pregnancy.

RESULTS

Between 2 consecutive pregnancies, 15.6% (115/739) of women seroconverted. Of these seroconversions, 29% (33/115) occurred in the periconceptional period or in the first trimester. The risks for cCMV and related sequelae (neurologic and/or hearing loss) following a maternal infection in the first trimester were, respectively, 24- and 6-fold higher (risk ratios, 24 [95% confidence interval {CI}, 10.8-62.3] and 6 [95% CI 1.5-24], respectively) than in the general pregnant population. Of all primary maternal infections and fetal infections in the first trimester, 88% (29/33) and 92% (11/12), respectively, occurred when the inter-pregnancy interval was ≤2 years.

CONCLUSIONS

Women seronegative at their first pregnancy with a subsequent pregnancy within 2 years have the highest risk of delivering a child with cCMV-related sequelae. These women should be made aware of the risk and given the opportunity of serology screening in the first trimester.