THE EFFECT OF PREGNANCY ON SURVIVAL IN WOMEN INFECTED WITH HIV - A SYSTEMATIC REVIEW OF THE LITERATURE AND METAANALYSIS

Objective To investigate the effect of pregnancy on disease progressio n and survival in women infected with HIV by a systematic review of th e literature and meta-analysis. Methods Appropriate publications were identified using electronic and hand searching of relevant journals fr om 1983 to 1996. Studies were included in the review if they were coho rt studies, either prospective or retrospective, or case-control studi es which investigated disease progression of pregnant women infected w ith HIV and included a control group of nonpregnant women infected wit h HIV for comparison. Methodological quality was assessed for each stu dy. Data were extracted for predetermined outcome measures. Sensitivit y analyses were performed to explore the association between pregnancy and disease progression for the following study characteristics: clin ical setting (developed or developing countries), methodological quali ty (high or poor) and whether studies had controlled for potential con founding. Results Seven studies, all prospective cohorts, were eligibl e to be included in the review. The summary odds ratio for the risk of an adverse maternal outcome related to HIV infection and pregnancy we re as follows: death 1.8 (85% CI 0.99-3.3); HIV disease progression 1. 41 (95% CI 0.85-2.33); progression to an AIDS-defining illness 1.63 (9 5% CI 1.00-2.67) and fall of CD4 cell count to below 200x10(6)/L 0.73 (95% CI 0.17-3.06). Sensitivity analyses showed that HIV progression i n pregnancy was significantly more common in a developing country sett ing (odds ratio 3.71, 95% CI 1.82-7.75) than in developed countries (o dds ratio 0.55, 95% 0.27-1.11) and also significantly more common in h igh quality studies when compared to low quality ones, odds ratios 3.7 1 (95% CI 1.82-7.57) and 0.55 (95% CI 0.27-1.11), respectively. Howeve r, there appears to be less progression of HIV disease and progression to AIDS when studies attempted to control for confounding by matching or restriction techniques, although this was not statistically signif icant in either case. Conclusions The findings of this review have imp lications for women infected with HIV who are pregnant or are consider ing a pregnancy. There does appear to be an association between advers e maternal outcomes and pregnancy in women infected with HIV, although this association is not strong. The relation may be due to the result of bias including residual confounding. Further large scale observati onal studies with long term follow up are required before this issue c an be fully resolved.