2: The effect of treatment of maternal CMV infection on the development of placental syndrome

Abstract

Cytomegalovirus (CMV) is known to infect trophoblasts and result in placental dysfunction. Our objective was to evaluate whether treatment of maternal CMV infection prevents “placental syndrome”, a composite of adverse pregnancy outcomes that involve placental dysfunction. Secondary analysis of a multicenter randomized placebo-controlled trial of CMV hyperimmune globulin (HIG) to prevent congenital CMV infection. Women were eligible for the trial if they had primary CMV infection—positive IgM antibody and positive low avidity (< 50%) IgG antibody before 24 weeks, or IgG seroconversion before 28 weeks—as analyzed in a single reference laboratory, and were carrying a singleton fetus without ultrasound abnormalities suspicious for congenital CMV infection. Trained research nurses abstracted the outcomes which were prespecified according to standard criteria. Placental syndrome was defined as any preeclampsia, gestational hypertension (GHTN), small for gestational age (SGA; birthweight < 10%ile), placental abruption, preterm delivery (PTD before 37 weeks), or perinatal death. We also evaluated the effect of treatment on severe placental syndrome defined as any of the following: preeclampsia or GHTN requiring delivery < 37 weeks, birthweight < 5%ile, PTD < 34 weeks, or perinatal death. P < 0.05 was used to denote statistical significance. The primary analysis showed that HIG did not prevent congenital infection. Of 399 women randomized, 390 had informative data for this analysis. Baseline characteristics were balanced between the treatment groups. Placental syndrome was significantly more common in the HIG group (Table). Each of the individual components of the placental syndrome, as well as severe placental syndrome and its components, occurred more often in the HIG group, but the differences were not statistically significance (Table). In this largest randomized trial to date, treatment of maternal CMV with hyperimmune globulin not only did not prevent congenital infection, but also increased the frequency of placental syndrome.