Z Geburtshilfe Neonatol 2013; 217 - Po07_2
DOI: 10.1055/s-0033-1361427

Barriers to achieving undetectable viral load in HIV-positive pregnant women at the time of delivery: The Swiss Mother & Child HIV Cohort Study

K Aebi-Popp 1, 2, T Glass 3, C Rudin 4, B Bertisch 5, B Martinez de Tejada 6, C Grawe 7, K Scheibner 8, M Rickenbach 9 I Hoesli 1, and the Swiss Mother & Child HIV Cohort Study
  • 1Universitätsfrauenklinik, Basel, Switzerland
  • 2St. James's Hospital, Genitourinary Medicine and Infectious Diseases, Dublin, Ireland
  • 3Swiss Tropical and Public Health Institute, Basel, Switzerland
  • 4Universitäts-Kinderspital, Basel, Switzerland
  • 5Kantonsspital, Infektiologie, St. Gallen, Switzerland
  • 6Universitätsfrauenklinik, Genf, Switzerland
  • 7Universitätsfrauenklinik, Zürich, Switzerland
  • 8Universitätsfrauenklinik, Bern, Switzerland
  • 9Institute for Social and Preventive Medicine, Lausanne, Switzerland

Background: Mother to child transmission rates in Europe are below 1% in HIV-infected women on combined antiretroviral therapy (cART) irrespective of mode of delivery. Actual Swiss guidelines recommend vaginal delivery for women with undetectable load (VL). The aim was to explore the barriers to achieving an undetectable VL at delivery.

Methods: HIV-1 positive women enrolled in the Swiss Mother & Child HIV Cohort Study between 2000 and 2011 were included. Logistic regression models were used to estimate factors associated with detectable VL at delivery.

Results: The analysis included 359 mother-child pairs. Mothers were a median of 27 years (range 15 – 47), 55.4% were black, 47.6% only completed the mandatory schooling, 11.5% had a history of injecting drug use, 20.4% consumed alcohol and 24.7% smoked during pregnancy. 95.8% of women were on cART during pregnancy with a median duration of 120 days (IQR: 81 – 154). 17.4% of women reported missing ≥1 dose of cART during pregnancy. 24% of women had a detectable VL at delivery. The percentage of women with undetectable VL and the rates of vaginal deliveries increased over time (Figure). In univariable analyses, detectable VL at delivery was associated with younger age (per year, odds ratio (OR) 0.97, 95% confidence interval (CI): 0.92 – 1.00), lower education (OR 0.56, 95% CI: 0.34 – 0.90), shorter time on ART (each additional week on ART, OR 0.95, 95% CI: 0.93 – 0.97), missed doses of cART (OR 1.34, 1.13 – 1.59) and year of delivery (OR 0.90, 95% CI: 0.82 – 0.99). In multivariable models, lower education (OR 0.59, 95% CI: 0.35 – 1.00) and shorter time on ART (OR 0.96, 95% CI: 0.94 – 0.98) remained significantly associated with detectable VL at delivery.

Conclusions: Major barriers to achieving undetectable VL at delivery appear to be insufficient time on cART due to late start or adherence issues and lower maternal education. Early HIV testing and engagement in care need to be addressed to achieve the aim of an undetectable VL at delivery.