Characteristics of pregnant women who seroconvert after an initial negative Human Immunodeficiency Virus test result at antenatal booking at selected hospitals in Lusaka, Zambia.

ABSTRACT Objectives:  To examine the role of demographic, socio-economic, health and reproductive characteristics of pregnant women and study the impact of their utilization of health services in relation to seroconversion after an initial negative HIV test result in women attending ANC at selected hospitals in Lusaka. Methods: This was a case control study conducted at the Women and Newborn Hospital and selected level 1 hospitals in Lusaka district between July 2018 and June 2019. Convenience sampling was used. Interviews were conducted using a structured interviewer administered questionnaire involving 47 women who seroconverted (as cases) and 140 women who did not seroconvert (as controls). Results: The study found that monthly income, age at sexual debut, number of sexual partners in a lifetime, children with the same father, partners who did not test for HIV before ANC booking, partner perceived to be faithful, frequent travel in partner and less than four ANC visits were associated with HIV seroconversion. However, when these factors where adjusted in multivariate logistic regression for confounders, women who had sexual debut before the age of 16 years were seven times more likely to seroconvert (AOR=6.67, 95%CI=1.103-39.805, P=0.039), those whose partners tested for HIV before ANC booking were 72 percent less likely to seroconvert  (AOR=0.278, 95%CI=0.089-0.865, P=0.027), those who partners travelled out of town frequently were three times more likely to seroconvert (AOR=3.250, 95%CI=1.063-9.935, P=0.039) and those who attended less than four ANC visits were three times more likely to seroconvert (AOR=3.378, 95%CI=1.018-11.210, P=0.047).   Conclusion: Pregnant women are at risk of seroconverting during pregnancy leading to MTCT of HIV. It is therefore imperative that HCT be strengthened during ANC and labour. Targeting adolescents with sexual and reproductive health education before they start engaging in sexual activities is key to keeping them HIV negative. Pre-exposure prophylaxis should be provided to pregnant women whose partners decline HCT or are HIV positive. Frequent travellers should be educated to practice safer sex. Lastly, there is need to implement the WHO 2016 ANC recommendation of at least 8 contacts during pregnancy. Key words: HIV seroconversion, elimination of mother-to-child transmission, window period.