Background: In May 2018, the Botswana Tsepamo study reported a higher rate of neural tube defects (NTDs) among infants of women who were using dolutegravir (DTG)-based antiretroviral treatment (ART) regimens at conception. The Botswana Ministry of Health and Wellness (MoHW) expanded NTD outcome surveillance in health facilities not covered by the Tsepamo study to capture additional pregnancies that were exposed to DTG at the time of conception.
Methods: Data on all deliveries (live births and stillbirths) at 22 facilities were collected from October 2018-March 2019 including maternal HIV status, exposure to ART at conception, and infant birth outcomes. Potential NTDs were identified by midwives before infant discharge from the facility and suspected NTDs were reviewed and classified by a clinical geneticist who was blinded to HIV and ART exposure status.
Results: The surveillance system captured of 3076 pregnancies. Of these, 76% (n=2328) pregnancies were among HIV-negative women, 24% (n=742) among HIV-positive women, and < 1% (n=6) among women with unknown HIV status. At conception, the majority (73%, n=544) of HIV-positive women were on ART; of these 28% (n=152) were on DTG. (Table 1). Six suspected NTDs were identified. Of these, one NTD was confirmed, two were classified as not NTDs, two as “probably NTDs”, and one as a “possible NTD”. Three NTDs were included in the final analysis (1 confirmed, 2 probable). One of these NTDs occurred among the 152 DTG-exposed HIV-positive mothers for a prevalence of 0.66% (95% CI 0.02% - 3.69%; Table 2).The other two NTDs occurred in the 2328 HIV-negative mothers for a prevalence of 0.09% (95% CI 0.01% - 0.31%).
Conclusions: Our findings suggest an increased birth prevalence of NTDs among infants born to HIV-positive mothers on DTG at the time of conception when compared to infants born to HIV-negative mothers, which is consistent with previous findings from the Tsepamo study.
The number of observed pregnancies in this study alone is too small to reliably detect differences in NTD prevalences that might exist. As such, these findings should be considered in combination with data from other studies to better assess any differential risks of NTDs associated with DTG.
The findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention.