Does HIV impact fertility in Africa?
by Alon Katz
In this study, researchers from the Centre for Population Studies at the London School of Hygiene and Tropical medicine set out to investigate whether HIV affects fertility in African populations by reviewing evidence from other publications. This is an interesting question because HIV is sexually transmitted and can be passed on from mother to child in the womb or during birth, but its impact on fertility is rarely mentioned despite the massive volume of HIV research that is done each year.
The research team demonstrated that the number of HIV positive women and the HIV negative women should theoretically have equal birth rates – this means that HIV itself doesn’t impact a woman’s ability to bring a child to term. They also delved into the rate at which pregnant woman catch HIV and compared it to the rate at which the general female population catches HIV. They then used the aforementioned figures to compare the birth rates of females in cohort studies with general clinical data about pregnancy cases. This method allowed them to come up with possible explanations for any differences that they might find.
What they found is that HIV positive females give birth to fewer children than HIV negative females in all sexually mature age groups, and the difference in fertility between infected and healthy females increases with age. Additionally, they found that regions which have been affected by HIV for longer exhibit a greater difference in fertility. The most notable finding is that there is a 0.4% decline in total fertility of a population for every percentage of the female population with HIV infection.
The authors concluded that stillbirths are the main cause of reduced fertility in HIV positive females, as they are more susceptible to coinfection by other sexually transmitted infections which can kill the foetus. In my view, the reduced fertility of HIV positive females in areas which have been affected by HIV for longer could be down to lack of data in areas which recently became affected by HIV or it is because people in regions which have been affected for longer are better informed about how HIV spreads and perhaps that informs their decision to have (or not have) children.
Zaba B, Gregson S. Measuring the impact of HIV on fertility in Africa. AIDS (London, England). 1998 ;12 Suppl 1:S41-50. PMID: 9677188.