HAART and adverse events during pregnancy explored in European study

Taking HAART during pregnancy is associated with premature delivery, according to European data published in the November 18^th edition of AIDS. The investigators also found that the initiation of HAART before pregnancy was particularly associated with premature delivery and that infants born prematurely had a high mortality rate.

These findings echo those of a UK study presented to the Seventh International Congress on Drug Therapy in HIV Infection in Glasgow last month.

Increasing numbers of HIV-positive women are taking HAART during pregnancy both to protect their own health and to prevent mother-to-baby transmission of HIV. Investigators from the European Collaborative Study noted a “worrying” increase in severe pregnancy-related adverse events in HIV-positive women taking HAART, including the death of their babies during the early weeks of life and described adverse outcomes during pregnancy amongst women taking HAART.

Since 1986 investigators from the European Collaborative Study have been collecting data on the outcome of pregnancy in HIV-positive women, including premature birth, severe premature birth, and neonatal death. Premature delivery was defined as birth before 37 weeks of gestation and severe premature delivery as birth before 34 weeks of gestation. Neonatal death was defined as the death of an infant with 28 days of birth.

From 1986 to the end of April 2004, a total of 4372 live births were recorded by the investigators. Overall, 19% of births were premature, but the investigators noted that the percentage of premature births increased significantly with the use of HAART during pregnancy (from 16% in the period of analysis ending in 1989 to 25% in 2004, trend p

A total of 66% of deliveries were by elective caesarean section at week 38 of pregnancy. However, the investigators noted that there was a trend for more emergency caesarean or vaginal deliveries to be performed since HAART became available during pregnancy (p

Women taking HAART were significantly more likely to give birth prematurely than women taking AZT monotherapy (26% versus 17%, p

When the investigators looked at severe premature delivery, they found an even stronger association with the use of HAART during pregnancy (p = 0.01 when HAART initiated during pregnancy, p

The investigators then looked at the clinical significance of premature and severely premature delivery. A total of 28 neonatal deaths were recorded between 1986 and 2004, the infants having a median gestation of 31 weeks and a median birthweight of 1213g. The neonatal mortality rate was 74 per 1000 for infants born before 34 weeks of gestation, compared to 2 per 1000 for infants born full-term.

Investigators were unable to perform multivariate analysis due to the small number of neonatal deaths, but noted a strong relationship between the length of gestation and death: 71% of infants who died were premature.

“Our findings of a substantially increased risk of severely curtailed pregnancy duration among women taking HAART antenatally, particularly when initiated pre-pregnancy, coupled with very high neonatal mortality rate associated delivery at these early gestations, are very concerning”, write the investigators.

The investigators note that HAART is effective at preventing mother-to-baby transmission of HIV but suggest “that these data are taken into consideration when making therapeutic decisions for HIV-positive women of childbearing ages whose clinical, immunological and virological status does not indicate a need for early initiation of HAART.”