BackgroundThere is little data evaluating uptake of first-line dolutegravir among men and women living with HIV in low- and middle-income countries, and subsequent clinical outcomes in non-trial settings. We aimed to determine dolutegravir uptake in women, and the impact of dolutegravir on clinical outcomes in routine care in South Africa.MethodsWe analysed de-identified data from adults receiving first-line ART at 59 South African clinics from December 2019 to February 2022, using two distinct cohorts. In the ‘initiator cohort’, we used Poisson regression models to assess initiation with dolutegravir-based ART by gender, and associations between dolutegravir use and 12-month retention-in-care and viral suppression <50 copies/mL. In the ‘transition cohort’, consisting of adults receiving non-dolutegravir-based first-line ART in December 2019, we used Cox proportional hazards models to assess the hazard of transition to first-line dolutegravir by gender. We then used time-dependent propensity score matching to compare subsequent 12-month retention-in-care and viral suppression between people transitioned to dolutegravir, and those who had not yet transitioned at the same timepoint.FindingsOf 45,392 adults initiating ART, 28,725 (63·3%) were women, median age was 31 years (IQR 26,38), and 31,264 (69·9%) initiated dolutegravir. Dolutegravir initiation was lower in non-pregnant (risk difference [RD] −18·4% [−21·6,−15·2]) and pregnant women (RD −35·4% [−42·3,−28·5]) versus men. At 12-months, retention-in-care (adjusted RD 5·2% [2·2,8·4)) and viral suppression (aRD 3·1% [1·2,5·1]) was higher in dolutegravir initiators.Among 180,956 adults receiving first-line ART in December 2019, median age was 38 years (32,45), 124,168 (68·6%) were women and 98·6% received efavirenz. By February 2022, 121,210/158,999 (76·2%) of those in care were transitioned to first-line dolutegravir. Transition was lower in women (hazard ratio 0·56, [0·56,0·57]). Among 92,318 propensity score matched people, 12-month retention-in-care (aRD 2·5% [2·1–2·9]) and viral suppression (aRD 0.8% [0.3,1.4]) were slightly higher in the dolutegravir versus non-dolutegravir group.InterpretationWomen were less likely to receive dolutegravir. As dolutegravir was associated with better outcomes, the rollout should continue, with a particular emphasis on inclusion of women.FundingWellcome Trust; Africa Oxford Initiative; International Association of Providers of AIDS Care, Bill & Melinda Gates Foundation