Association between pregnancy at enrollment into HIV care and loss to care among women in the Democratic Republic of Congo, 2006-2013

Background Loss to care is high among asymptomatic HIV-infected women initiated on antiretroviral therapy (ART) during pregnancy or in the postpartum period. However, whether pregnancy itself plays a role in the high loss to care rate is uncertain. We compared loss to care over seven years between pregnant and non-pregnant women at enrollment into HIV care in the Democratic Republic of Congo (DRC). Methods We conducted a retrospective analysis of all ART-naive women aged 15-45 initiating HIV care at two large clinics in Kinshasa, DRC, from 2007-2013. Pregnancy status was recorded at care enrollment. Patients were classified as having no follow-up if they did not return to care after the initial enrollment visit. Among those with at least one follow-up visit after enrollment, we classified patients as lost to care if more than 365 days had passed since their last clinic visit. We used logistic regression to model the association between pregnancy status and no follow-up, and Cox proportional hazards regression to model the association between pregnancy status and time to loss to care. Results Of 2175 women included in the analysis, 1497 (68.8%) were pregnant at enrollment. Compared to non-pregnant women, pregnant women were less likely to be over 35 years of age (19.1% vs. 31.9%, p<0.0001) and less likely to be in WHO stage III or IV (9.0% vs. 26.3%, p<0.0001). Among pregnant women, 106 (7.1%) were not seen after enrollment, versus 25 (3.7%) non-pregnant women (adjusted odds ratio 2.01, 95% CI 1.24-3.24). Of the 2,044 women with at least one follow-up visit, 46.5% of pregnant women and 46.7% of non-pregnant women were lost to care by 5 years; hazards of loss to care were similar for pregnant and non-pregnant women (adjusted hazard ratio 1.08, 95% CI 0.93-1.26). Conclusions In this large cohort of HIV-infected women, patients pregnant at care enrollment were more likely to never return for follow-up. Among those who attended at least one follow-up visit, loss to care was not different between pregnant and non-pregnant women, suggesting that pregnancy itself may not be the main driver of the high attrition observed in this cohort.