Repeat antenatal HIV testing in the third trimester: a study of feasibility and maternal uptake rates

The study aimed to assess the feasibility and acceptability of third-trimester antenatal HIV testing within our service after two cases of HIV seroconversion in pregnancy were noted in 2008. North American Guidelines recommend universal third-trimester HIV testing in areas with an HIV prevalence of more than 1 per 1000. The HIV prevalence rate in our area is 3.01 per 1000.

Pregnant women prior to 28 weeks of gestation were recruited at booking between 1 September 2008 and 31 August 2009 and offered an additional third-trimester HIV test. Consent was obtained and testing was performed by hospital and community midwives. Information was entered into a modified existing electronic maternity database. A qualitative e-mail survey of midwives investigated barriers to participation in the study.

A total of 4134 women delivered; three (< 0.1%) declined first-trimester testing. Twenty-two women (0.5%) tested HIV positive, of whom six were newly diagnosed. Overall, 2934 of 4134 women (71%) were offered and accepted a third-trimester HIV test and had results available. Data were unavailable for 195 women (4.7%). A total of 663 of 4131 women (16%) were not offered a third-trimester test. Of 3273 women documented as having been offered a test, 3177 (97.1%) accepted. There were no positive third-trimester tests. Forty of 50 (80%) midwives surveyed responded with questionnaire feedback and cited lack of national policy and extra workload as barriers to performing third-trimester testing.

Third-trimester testing was feasible and consent rates were high in those offered repeat testing. Third-trimester testing has the potential to prevent paediatric HIV infection and universal testing should be considered in high-prevalence areas.