HIV incidence among pregnant and postpartum women in a high prevalence setting

In sub-Saharan Africa, most women who test HIV negative at the first antenatal care encounter are rarely tested again during pregnancy and postpartum, yet data suggests that pregnancy is associated with increased risk of HIV acquisition compared to non-pregnant women. We describe HIV incidence during pregnancy and postpartum in Lesotho, a high prevalence setting, and factors associated with HIV seroconversion. We enrolled a cohort of HIV negative women presenting at health facilities for antenatal care and followed them through delivery up to 24 months postpartum. Women were repeatedly tested for HIV according to the Lesotho Ministry of Health routine rapid HIV testing guidelines and responded to risk behavior questionnaire every three months. We estimated HIV incidence and associated 95% confidence intervals. We used mixed effects Cox regression models to identify independent factors associated with seroconversion accounting for repeated assessment. The estimated overall HIV incidence rate was 1.58 (95% CI: 1.05–2.28) per 100 person- years. The estimated HIV incidence rate during pregnancy (2.61 per 100 person-years, 95% CI: 1.12–5.14) was almost double the estimated HIV incidence during postpartum (1.36 per 100 person-years, 95% CI: 0.83–2.10). Women’s age (14–24 years compared to 25–45 years), multiple sexual partnerships, urethral discharge and no condoms nor pre-exposure prophylaxis were independently associated with HIV infection. There is an increased need for counseling and support of HIV-uninfected pregnant and breastfeeding women to stay HIV-negative, including provision of pre-exposure prophylaxis during this high-risk period, particularly among adolescent and young women.

在撒哈拉以南非洲地区，多数首次产前检查时人类免疫缺陷病毒（HIV）检测呈阴性的女性，在孕期及产后阶段极少再次接受HIV检测；但现有数据显示，与非妊娠女性相比，妊娠状态会提升HIV感染风险。本研究针对高HIV流行率国家莱索托，描述其孕期及产后阶段的HIV感染发生率，并分析与HIV血清转换相关的影响因素。本研究招募了在医疗机构就诊、初检HIV阴性的产前保健女性队列，对其进行随访至分娩后24个月。研究对象按照莱索托卫生部常规快速HIV检测指南多次接受HIV检测，并每三个月填写一次风险行为问卷。本研究估算了HIV感染发生率及其对应的95%置信区间（95% CI），并采用混合效应Cox回归模型，结合重复评估的设计，识别与血清转换相关的独立影响因素。估算得到的总体HIV感染发生率为1.58例/100人年（95% CI：1.05~2.28）。孕期HIV感染发生率估算值为2.61例/100人年（95% CI：1.12~5.14），几乎是产后阶段（1.36例/100人年，95% CI：0.83~2.10）的两倍。研究发现，年龄处于14~24岁（相较于25~45岁）、存在多性伴行为、伴有尿道分泌物，以及未使用安全套或未采取暴露前预防（pre-exposure prophylaxis）的女性，其HIV感染风险显著升高，均为独立相关因素。因此，需进一步加强对HIV阴性妊娠及哺乳期女性的咨询与支持，帮助其维持HIV阴性状态，包括在这一高风险阶段提供暴露前预防干预，尤其需关注青少年与年轻女性群体。