Maternal CD4 + microchimerism in HIV-exposed newborns after spontaneous vaginal delivery or caesarean section

BackgroundMaternal CD4 + cell microchimerism may be greater after caesarean section compared to spontaneous vaginal delivery and could cause mother-to-child transmission (MTCT) in HIV-exposed newborns.AimsTo evaluate maternal CD4 + cell microchimerism in HIV-exposed newborns after spontaneous vaginal delivery or caesarean section.Study design and subjectsIn this prospective single-centre study, neonates whose mothers were infected with HIV and had normal MTCT risk according to the German Austrian Guidelines were considered for study enrolment. Maternal CD4 + cell microchimerism in the newborns' umbilical cord blood was measured and compared by mode of delivery.ResultsThirty-seven HIV-infected mothers and their 39 newborns were included in the study. None of the 17 (0.0%) newborns delivered vaginally had quantifiable maternal CD4 + cells (95% confidence interval (CI): 0.00–0.00) in their circulation at birth compared with four of 16 (25.0%) newborns delivered via planned caesarean section, who showed 0.01–0.66% maternal cells (95% CI: − 0.06–0.16; P = 0.02) in their circulation. The intention to treat analysis, which included six additional newborns delivered by unplanned caesarean section, showed quantifiable maternal CD4 + cells in one (0.05%; 95% CI: − 0.02–0.04) of 23 (4.3%) newborn at birth compared to four of 16 (25.0%) born via planned caesarean section (95% CI: − 0.06–0.16; P = 0.04). There was no MTCT in any of the newborns.ConclusionIn this small cohort, spontaneous vaginal delivery in HIV-infected women with normal MTCT risk was associated with lower maternal CD4 + cell transfer to newborns compared to planned caesarean section.