Population-level impact of hormonal contraception on incidence of HIV infection and pregnancy in women in Durban, South Africa
Gita Ramjee & Handan Wand
Volume 90, Number 10, October 2012, 748-755
Table 3. Population-level impact of use of hormonal and other contraceptives, at baseline and follow-up, in terms of HIV-1 seroconversion and pregnancy rates during study, Durban, South Africa, 2004–2009
| Outcome | Crude PAR% (95% CI) | Partial PAR%a (95% CI) |
|---|---|---|
| HIV-1 seroconversion | ||
| Hormonal contraceptivesb (at baseline only) | 12 (10–16) | 6 (4–8) |
| Hormonal contraceptivesb (during follow-up only) | 15 (12–18) | 7 (5–10) |
| Hormonal contraceptives (at baseline and follow-up) | 20 (16–22) | 12 (9–16) |
| Pregnancy | ||
| Other types of contraceptivesc (at baseline only) | 54 (48–59) | 58 (52–63) |
| Other types of contraceptivesc (during follow-up only) | 36 (26–48) | 44 (35–54) |
| Hormonal contraceptives (at baseline and follow-up) | 63d (55–70) | 72 (66–77) |
CI, confidence interval; HIV-1, human immunodeficiency virus type 1; PAR%, population-attributable risk per cent.
a Adjusted for age (< 25, 25–34, 35+ years); multiple sex partners; no condom use by partner in most recent sexual act, and having been diagnosed with an sexually-transmitted infection (at least one test positive for Neisseria gonorrhoea, Chlamydia trachomatis, Trichomonas vaginalis or syphilis) at baseline.
b Injectables and pills.
c Includes intrauterine devices, spermicides and traditional methods such as rhythm and abstinence.
d In other words, if women who reported using non-hormonal contraceptive methods (at baseline and follow-up) had used hormonal contraceptives instead, 63% of all pregnancies could have been avoided.