HIV and pregnancy : an epidemiological, clinical and virological study of HIV-infected pregnant women and their offspring

Sammanfattning: Background: HIV infection is spread throughout most parts of the world with a substantial risk for a fatal outcome within 10 years. The virus is transmitted sexually, by infected blood and from mother to child. Whether the course of am HIV infection in women is changed by pregnancy is not known. The infection is transmitted during pregnancy, at delivery and by breast-feeding in between 15% and 40% on the average. Women with a symptomatic HIV infection or AIDS, p24 antigenaemia, low CD4 cell counts and/or a high viral burden are more likely to transmit the infection. The aim of this investigation was to study the interaction between HIV and pregnancy. The main concerns were the possible HIV activation by pregnancy and the substantial risk for the child. Subjects and Methods: HIV testing was offered to pregnant women at antenatal care units (ACU) and abortion clinics in order to identify previously unaware HIV-infected women. The purpose was to offer counselling, care and information about preventive measures and to develop a comprehensive model, also considering the psychological and social consequences for the affected families. Through clinical, immunological and virological monitoring of childbearing and terminating women during and six months after pregnancy, attempts were made to evaluate possible signs of HIV activation. By searching for HIV in fetuses and children by virus isolation, the polymerase chain reaction and in situ hybridisation, attempts were made to estimate frequencies and timing of mother-to-offspring transmissions. In addition, the clinical outcomes of mothers and children were evaluated in relation to maternal disease and mother-to-child transmission. Results and Conclusions: Seventy of the included 155 women were diagnosed with HIV in the national pregnancy screening programme, in which approximately 1/10 000 tests were HIV positive, with higher incidences in Stockholm (2.38/10 000) than in the rest of the country (0.57/10 000)(p<0.001) and in abortion clinics (4.4/10 000) compared to ACUs (1.8/10 000) (p<0.05). Of the 155 women, 76 were African, 65 European - 60 Swedish - and 12 Asian or from the American continents. Twenty-six women were, or had been, drug users seven had become infected by blood transfusions and 120 were classified as sexually infected. The origins and transmission routes of two women were not reported. Approximately 50% of the pregnant women who were able to make an informed pregnancy decision terminated the pregnancy; more frequently they were women without a steady partner and in unstable social circumstances. There were no major HIV-related complications during pregnancy or postpartum/postabortum in 105 of 107 clinically studied women. The virus isolations, the CD4 cell counts and the p24 antigen results during pregnancy and six months later showed high frequencies of plasma and cell viraemia and indicated a relatively stable HIV activity during pregnancy and possible activation within six months after delivery. In 12 studied fetuses and in 27 children studied from birth, HIV infection was not confirmed in any of the fetuses or newborns. Within six months, 5 of 19 children, three of them studied also at birth, were shown to be infected, indicating an efficient placental barrier. The frequency of transmission was higher when the mother had been infected for more, compared to less, than two years at delivery. There were no reported primary HIV infections during pregnancy. At follow-up, after a median time of 29 months, 46% of the childbearing women (giving birth before 1991) had shown progression in their infection, more frequently in mothers of infected children. Much time was needed for pregnancy counselling and support, especially when the woman was diagnosed with HIV during pregnancy. Many women lived with an uninfected partner, who would become the caretaker after the woman's death. Still, between one third and one half of the children were at risk of being orphaned. The medical, psychological and social consequences of HIV were overwhelming. The women, their partners and children required much support to cope and live with HIV.