Cytomegalovirus in HIV-Positive Pregnant Women Increases Risk of Mother-to-Child Transmission

HIV-positive pregnant women with detectable cytomegalovirus (CMV) are more than 5 times more likely to transmit the virus to their infant, a new study found.

In a study published in Clinical Infectious Diseases, investigators sought to determine whether CMV urinary shedding increases the risk for congenital cytomegalovirus infection (cCMV) in pregnant women with HIV.

The perinatal NICHD HPTN 040 study included a subset of mother-infant pairs, untreated with antiretrovirals before labor. The investigators collected urine from the mothers and infants to test for CMV DNA using qualitative real-time polymerase chain reaction (RT-PCR).

Urine specimens were available for 260 women, of whom, 24 had detectable CMV viruria by qualitative PCR. No association was found between maternal CMV viruria and mean CD4 cell counts or HIV viral load. However, an association was observed with younger maternal age.

Of the 250 infants, 10 had cCMV. Women with detectable peripartum CMV viruria were more likely to have infants with cCMV compared with those without it (20.8% versus 2.1%, respectively).

The study also showed that women with CMV viruria had significantly higher rates of HIV perinatal transmission, with 29.2% versus 8.1%, respectively.

Women with CMV viruria were 5 times more likely to transmit HIV to their infants and nearly 30 times more likely to transmit CMV. Additional findings showed that maternal gonorrhea and higher maternal HIV log10 viral loads were a significant risk factor for cCMV.

Approximately 1 of every 200 babies are born with cCMV, but only about 1 of 5 with the infection will become sick from the virus or have long-term health problems, according to the CDC. Long-term health problems include: hearing and vision loss, intellectual disability, small head size, lack of coordination, muscle weakness, and seizures.

“In this cohort of HIV-infected pregnant women not on antiretrovirals, urinary CMV shedding was a significant risk factor for CMV and HIV transmission to infants,” the authors concluded.

Study limitations included a sample size that was determined by the availability of urine samples from the women. Additionally, the data used from the overall study included women who were diagnosed with HIV at the time of labor and delivery, meaning the UCLA-led research was not applicable to HIV-positive pregnant women on antiretroviral therapy during pregnancy, according to the authors.