Maternal Screening for Down Syndrome Accurate in HIV-Infected Women

Maternal biochemical serum screening for Down syndrome in pregnancy is accurate in HIV-infected women, according to a report in the August Obstetrics & Gynecology.

Dr. Elie Azria from Port Royal Maternity, Paris, France told Reuters Health that reliability of the Down syndrome screening test in this population has been considered poor on the basis of very small studies with poor levels of evidence. Dr. Azria added, "I hope this study will promote the message that this test is not less accurate in this population of pregnant women and that physicians will not discourage women who want it, to do it."

Dr. Azria and colleagues estimated the influence of HIV infection and antiretroviral therapy on maternal levels of alpha-fetoprotein (AFP) and hCG and the false-positive rate of maternal biochemical screening for Down syndrome.

HIV-infected women had lower median AFP levels than did control women, but the difference was not statistically significant, the authors report. Similarly, total hCG levels did not differ between HIV-infected and control women.

False-positive rates did not differ between HIV-infected women and control women, the researchers note, regardless of whether HIV-infected women were treated with antiretroviral therapy.

"Down syndrome screening is performed on the basis of voluntary participation after clear information, and this screening has to be at every pregnant woman's disposal and can't be refused if a woman with a single pregnancy asks for it, whatever her HIV status or treatment," Dr. Azria said.

"The amniocentesis risk is known on not-infected women and this risk has to be explained," Dr. Azria added. "But on the issue of liquid leakage and fetal loss, the risk of mother to child transmission of HIV is not very well known. Our duty is thus to inform women, not only on the screening test availability but also on the possible consequences of a positive test for the pregnancy."

Obstet Gynecol 2008;112:223-230