The incidence of HIV transmission in twins joined that of singleton pregnancies

The advent of HAART has reduced the rate of HIV transmission from a mother to her twins, bringing the observed level in single pregnancies, according to a French study published in Aids.

Due to an increased incidence of preterm birth and premature rupture of membranes, twin pregnancies are an additional risk of vertical transmission of HIV, reminded the APM one of the authors, Dr. Laurent Mandelbrot, who directs the department of gynecology and obstetrics of Louis Mourier (AP-HP Hauts-de-Seine Colombes) hospital.

This risk is of particular concern because the twins are more common in people with HIV than in the general population, as confirmed by the study with his colleagues on the French Perinatal Survey (EPF), which lists since 1986, births to HIV + mothers followed in 90 centers.

While the prevalence of twin pregnancies is estimated at 1.4% for the whole of French, it is 2.5% for EPF participants who gave birth between 2000 and 2004, a proportion that was only 0, 6% between 1984 and 1987.

The increase would come from the increased age of women in labor, and the increasing share of HIV among women of African descent, a higher risk of multiple pregnancies that European explains Laurent Mandelbrot.

Since 2003 is added another factor, the practice among women of medically assisted procreation (MAP) to protect their partners from HIV, a technique that promotes multiple pregnancies.

Because of this phenomenon, still marginal in 2004, the proportion of twin pregnancies could increase, accompanied by an increase in premature births, with all the associated health risks, beyond the issue of HIV. "It makes us necessarily fear," says Laurent Mandelbrot.

On vertical transmission, the study, which focuses on 9262 192 twin births which shows that the emergence of triple coincides with a sharp decline for all types of pregnancies, and similar effects between twins and other children.

Before 1994, when zidovudine (Retrovir * GSK) has been used for the prevention of vertical transmission, the infection rate was 34.4% and in twin pregnancies, against 17.4% for singles. Despite the fall recorded between 1994 and 1996, the gap between the two groups was maintained, with respective incidences of 19.1% and 6.7% during this period.

It was not until 1997, with the advent of dual-and triple therapies for prevention, the difference is completely attenuated, with incidences of 0.9% and 1.8%, non-significant difference of that only a twin pregnancy on 111 recorded between 1997 and 2004 were affected.

For pregnant women who show no indication of treatment for themselves, current guidelines recommend starting treatment late in the second quarter for single pregnancies, and early in the presence of a risk factor prematurity, such as multiple pregnancies.

This advance would thus compensate for the risk of premature birth, which by reducing the duration of treatment exposure, promote transmission.

Several studies have also suggested that some antiretroviral drugs, including protease inhibitors, were associated with an increased risk of prematurity, results have not found other teams themselves.