Table 5.
HIV Acquisition Probability and Relative Risk (RR) of HIV Acquisition Among 2751 African Women With HIV-Infected Male Partners, by Reproductive Stage
| Reproductive Stage | Base Modela | Adjusted Modelb | ||||
|---|---|---|---|---|---|---|
| Probabilityc of HIV Acquisition per Condomless Sex Act (95% CI) | RRd for per-Act Probability of HIV Acquisition (95% CI) | P | Probabilityc of HIV Acquisition per Condomless Sex Act (95% CI) | RRd for per-Act Probability of HIV Acquisition (95% CI) | P | |
| Early pregnancy through postpartum period | 0.0027 (0.0009, 0.0074) | 4.97 (2.95, 8.38) | <.001 | 0.0029 (0.004, 0.0093) | 2.76 (1.58, 4.81) | <.001 |
| Early pregnancy | 0.0018 (0.0003, 0.0070) | 3.20 (1.24, 8.25) | .02 | 0.0022 (0.0004, 0.0093) | 2.07 (0.78, 5.49) | .14 |
| Late pregnancy | 0.0031 (0.0008, 0.0102) | 5.54 (2.62, 11.69) | <.001 | 0.0030 (0.0007, 0.0108) | 2.82 (1.29, 6.15) | .01 |
| Postpartum period | 0.0044 (0.0008, 0.0167) | 7.80 (3.04, 20.02) | <.001 | 0.0042 (0.0007, 0.0177) | 3.97 (1.50, 10.51) | .01 |
| Nonpregnant/nonpostpartum periods | 0.0005 (0.0003, 0.0009) | 1.00 | … | 0.0011 (0.005, 0.0019) | 1.00 | … |
Early pregnancy was defined as the interval from the start of pregnancy (typically the time of the last menstrual period) to gestation week 13. Late pregnancy was defined as the interval from gestation week 14 to the end of pregnancy. The postpartum period was defined as the interval from the end of pregnancy to month 6 after delivery (for women with live births), week 6 after pregnancy loss (for women with pregnancy loss at gestation week ≥20 or newborn death), or week 4 after pregnancy loss (for women with pregnancy loss during gestation weeks 6–19).
Abbreviations: CI, confidence interval; PrEP, preexposure prophylaxis.
aAdjusted for condom use and reproductive stage.
bAdjusted for condom use, reproductive stage, male partner viral load, female partner age, and active PrEP for women randomly assigned to receive and dispensed active PrEP in the Partners PrEP study.
cAdjusted absolute HIV acquisition probabilities among female partners represent infectivity estimates per condomless sex act with an HIV-infected partner with a viral load of 10 000 copies/mL for a 25-year-old female partner not taking PrEP.
dThe reference group for the adjusted model represents a condomless sex act with an HIV-infected partner with a viral load of 10 000 copies/mL for a 25-year-old female not taking PrEP occurring while the woman is not pregnant or is in the postpartum period.