RESUMO
OBJECTIVE: To evaluate the impact of type and timing of antiretroviral therapy (ART) on the risk of preterm delivery (PTD) and small-for-gestational age (SGA) birth among pregnant women and people living with HIV in Canada. METHODS: Data for this retrospective cohort study were analyzed from the Canadian Perinatal HIV Surveillance Program from 1990 to 2020. The association between ART and risk of PTD (<37 weeks) and SGA birth (<10th percentile) was explored using mixed effects logistic regression and time-dependent Cox proportional hazards models. RESULTS: Overall, there were 14.9% (654 of 4379) PTD and 18.5% (732 of 3947) SGA cases. A higher risk of PTD was observed with nonnucleoside reverse transcriptase inhibitor-(adjusted hazard ratio [aHR], 1.73; P = 0.019) and boosted protease inhibitor- (aHR, 186; P = 0.007) based regimens compared with integrase strand transfer inhibitor (INSTI)-based regimens. ART initiation prior to conception was associated with a lower risk of SGA birth compared with ART initiation after conception at 1 to 14 weeks (adjusted odds ratio [aOR], 0.69; P = 0.024) and > 14 weeks (aOR, 0.70; P = 0.005). CONCLUSION: INSTI-based ART regimens were associated with lower risk of PTD compared with other regimens, and ART initiation before conception was associated with a lower risk of SGA birth. These findings, with overall safety data, should be considered when providing pregnancy counseling to people living with HIV.
