Temporary cessation of antiretroviral treatment (ART) during pregnancy in women infected with HIV is an additional major risk factor for mother-to-child transmission of the virus, Italian researchers report in the May 1st issue of Clinical Infectious Diseases.

HIV

“Our study,” lead investigator Dr. Luisa Galli told Reuters Health, “provides evidence that interruption of ART during pregnancy increases HIV-1 mother-to-child transmission, either when ART is stopped in the first trimester and subsequently restarted, or when it is interrupted in the third trimester.”

Dr. Galli of the University of Florence and colleagues prospectively studied 937 pregnant women. ART was interrupted in 81 (8.6%) in the first trimester and in 11 (1.2%) in the third trimester. Corresponding median times without treatment were 8 weeks and 6 weeks.

Plasma viral load was similar in women who did and did not have their treatment interrupted, and the rate of mother-to-child transmission overall was 1.3%. However, the rate was 4.9% when ART was interrupted in the first trimester and 18.2% when it was interrupted in the third trimester.

“In fact,” continued Dr. Galli, “temporary discontinuation leads to a tenfold increase of mother-to-child transmission, overcoming, particularly in HAART-treated women, all other risk factors, except for the independent factor of high viremia — more than 10,000 copies/mL — at delivery.”

“These findings,” she concluded, “reinforce current guideline recommendations, which suggest to continue ART in HIV-1 pregnant women, even in the first trimester.”