The association between polyhydramnios and CMV infection–retrospective cohort study

Objective: Polyhydramnios was suggested to be associated with CMV infection, resulting in polyhydramnios being common indication for CMV testing. However, the literature does not provide a robust evidence to support this management. We aimed to examine the association between congenital CMV infection and polyhydramnios. Methods: A retrospective cohort study was conducted. The rate of polyhydramnios was analyzed in 63 neonates/fetuses with CMV between 2013 and 2017 and compared to 351 neonates without CMV using PCR targeted to the viral DNA. The rate of oligohydramnios and small for gestational age was also evaluated. Results: All cases of polyhydramnios were of isolated polyhydramnios without malformations. The rate of polyhydramnios was six (9.5%) and 23 (6.6%) pregnancies with and without congenital CMV, respectively (p =.42). Persistent polyhydramnios (more than one documented event) was evident in one (1.6%) and 13 (3.7%) pregnancies in the positive and negative CMV groups, respectively (p =.36). The rate of congenital CMV was similar with and without oligohydramnios (6, 9.5% versus 17, 4.8%, respectively; p =.14) and with or without small for gestational age neonate (7, 11% versus 63, 18%, respectively; p =.18). Conclusion: The results of this study do not support an association between CMV infection and polyhydramnios. The need for CMV testing in isolated polyhydramnios should be reevaluated.