This study was undertaken to analyze the outcomes of PPTCT services in an urban population in Southern India, and to study the factors influencing vertical transmission of HIV.

The study was undertaken in the Antiretroviral Therapy (ART) center and Integrated Counseling and Testing Center (ICTC) at four government Obstetric Institutes in Chennai, India from January 2009 to Febuary 2012 (including 18 months follow up). All pregnant women in the study setting from January 2009 to August 2010 were screened for HIV by ELISA test. HIV-positive pregnant women referred from distant places for institutional delivery, and those who were unlikely to be followed for 18 months for any reasons, were excluded. The study was conducted after the Institute’s ethical approval and informed written consent of the parents.

Three mL of blood was collected in vacutainer containing EDTA. DNA PCR testing was performed using Amplicor HIV-1 DNA v1.5 kit (Roche molecular Diagnostics, NJ, USA). CD4/CD8 T cell counting was performed on the BD FACSCalibur flow cytometer. CD4/CD8 percentage and absolute counting was performed according to the instructions provided by the manufacturer. Whole blood HIV 1 DNA PCR was done for all infants at 6 weeks of age. If the infant was PCR- positive, the test was repeated with a new blood sample as soon as possible, to confirm diagnosis before disclosure to parents. A second PCR test was done in all PCR-negative infants at 6 months or 6 weeks after stopping breastfeeds [1]. A negative test was disclosed only after the second PCR test was negative, and the child was no longer exposed to breastfeeds. All children were followed up to 18 months with assessment of nutritional status and for evidence of any clinical markers of HIV like oral candidiasis, recurrent respiratory infections, chronic suppurative otitis media, lymphadenopathy, hepatomegaly, parotid swelling, eczema, and molluscum contagiosum, at each visit. HIV ELISA was done at 18 months of age. ART was started to HIV-positive babies according to NACO guidelines [1]. ART regimen was triple drug (Stavudine, Lamivudine, Nevirapine) as Fixed Dose Combination (FDC) based on weight of infant.

There were 79,268 deliveries during the study period; 176 (0.22%) mothers were HIV ELISA positive (Fig.1). Seventy-six mothers were excluded because they were referred from distant secondary-care hospitals for delivery or because they were unlikely to be followed for 18 months for social reasons.

Fig.1 Study population and follow-up.

One hundred included women were divided into three groups based on CD4 counts <200 (n=5), 200 to 350 (n=19) and >350 (n=76). HIV clinical staging in pregnant women was Stage 1 (n=33), Stage 2 (n= 55), Stage 3 (n=10) and Stage 4 (n= 2). Thirty seven mothers were on triple drug ART. The median gestational age of starting ART was 16 (IQR 0, 28) weeks. The mean (SD) birth weight of the infants was 2710 (344) g. Twelve were born preterm. Forty-two infants were born by vaginal delivery and 58 by Caesarean section.

All 100 neonates received single dose Nevirapine soon after delivery. Sixty mothers chose to breastfeed. Among the breastfed, only three infants were breastfed for the entire 6 months; others were breastfed for variable periods from 1 month to 5 months and were switched to replacement feeds. The median (IQR) duration of breast feeding was 3 (2, 3.5) months. Forty mothers chose replacement feeds (artificial formula or undiluted cow’s milk) from day 1 of life. There was no mixed feeding.

Though transmission rates were 6.7% and 0% in breastfed and non-breastfed groups, respectively; we do not attribute PCR positivity to breastfeeding alone as three of the four infants were PCR-positive at 6 weeks of life. This was probably due to intrapartum transmission. Palombi, et al. [15] showed a transmission rate of <2% with alternatives to breastfeeding without an increase in mortality in non-breastfed group. The cumulative HIV-free survival at 18 months in our study was similar to that reported in an earlier study [9].

The limitations of our study were small sample size, and that our study population mostly belonged to lower and lower-middle class which may not be representative of the entire population.

We conclude that the overall parent-to-child transmission rate of HIV is low when the pregnant women receive ART, and single dose Nevirapine is given to the infants, simultaneously avoiding mixed feeding.

Acknowledgement: Project Director, Tamilnadu State AIDS Control Society.

Contributors: SS, SS: conceived and designed the study; SS, NV: followed up with the patients, conducted clinical assessment, collected data; AS, RK: conducted and laboratory tests, and data analysis; SS: drafted the manuscript; VS, SS: critical revision of the manuscript for important intellectual content. All authors approved the final version of manuscript.

Funding: Indian Council of Medical Research; Competing interests: None stated.