Incidence of Childbirth, Pregnancy, Spontaneous Abortion, and Induced Abortion Among Women With Human Immunodeficiency Virus in a Nationwide Matched Cohort Study

Background
Reproductive health in women with human immunodeficiency virus (HIV) (WWH) has improved in recent decades. We aimed to investigate incidences of childbirth, pregnancy, spontaneous abortion, and induced abortion among WWH in a nationwide, population-based, matched cohort study.

Methods
We included all WWH aged 20–40 years treated at an HIV healthcare center in Denmark from 1995 to 2021 and a matched comparison cohort of women from the general population (WGP). We calculated incidence rates per 1000 person-years and used Poisson regression to calculate adjusted incidence rate ratios (aIRRs) of childbirth, pregnancy, spontaneous abortion, and induced abortion stratified according to calendar periods (1995–2001, 2002–2008, and 2009–2021).

Results
We included 1288 WWH and 12 880 WGP; 46% of WWH were of African origin, compared with 1% of WGP. Compared with WGP, WWH had a decreased incidence of childbirth (aIRR, 0.6 [95% confidence interval, .6–.7]), no difference in the incidence of pregnancy (0.9 [.8–1.0]) or spontaneous abortion (0.9 [.8–1.0]), but an increased incidence of induced abortion (1.9 [1.6–2.1]) from 1995 to 2021. The aIRRs for childbirth, pregnancy, and spontaneous abortion increased from 1995–2000 to 2009–2021, while the aIRR for induced abortion remained increased across all time periods for WWH.

Conclusions
From 1995 to 2008, the incidences of childbirth, pregnancy, and spontaneous abortion were decreased among WWH compared with WGP. From 2009 to 2021, the incidence of childbirth, pregnancy, and spontaneous abortion no longer differed among WWH compared with WGP. The incidence of induced abortions remains increased compared with WGP.