Incidence, Patterns, and Predictors of Repeat Pregnancies Among HIV-Infected Women in the United Kingdom and Ireland, 1990-2009

Objective: To explore the pattern of repeat pregnancies among diagnosed HIV-infected women in the United Kingdom and Ireland, estimate the rate of these sequential pregnancies, and investigate the demographic and clinical characteristics of women experiencing them. Design: Diagnosed HIV-infected pregnant women are reported through an active confidential reporting scheme to the National Study of HIV in Pregnancy and Childhood. Methods: Pregnancies occurring during 1990-2009 were included. Multivariable analyses were conducted fitting Cox proportional hazards models. Results: There were 14,096 pregnancies in 10,568 women; 2737 (25.9%) had 2 or more pregnancies reported. The rate of repeat pregnancies was 6.7 (95% confidence interval: 6.5 to 7.0) per 100 woman-years. The proportion of pregnancies in women who already had at least 1 pregnancy reported increased from 20.3% (32 of 158) in 1997 to 38.6% (565 of 1465) in 2009 (P < 0.001). In multivariable analysis, the probability of repeat pregnancy significantly declined with increasing age at first pregnancy. Parity was also inversely associated with repeat pregnancy. Compared with women born in the United Kingdom or Ireland, those from Europe, Eastern Africa, and Southern Africa were less likely to have a repeat pregnancy, whereas women from Middle Africa and Western Africa were more likely to. Maternal health at first pregnancy was not associated with repeat pregnancy. Conclusions: The number of diagnosed HIV-infected women in the United Kingdom and Ireland experiencing repeat pregnancies is increasing. Variations in the probability of repeat pregnancies, according to demographic and clinical characteristics, are an important consideration when planning reproductive health services and HIV care for people living with HIV.