HIV-1 and HIV-2 prevalence, risk factors and birth outcomes among pregnant women in Bissau, Guinea-Bissau: a retrospective cross-sectional hospital study

Abstract

The human immunodeficiency virus (HIV) remains a leading cause of maternal morbidity and mortality in Sub-Saharan Africa. Prevention of mother-to-child transmission (PMTCT) has proven an effective strategy to end paediatric infections and ensure HIV-infected mothers access treatment. Based on cross-sectional data collected from June 2008 to May 2013, we assessed changes in HIV prevalence, risk factors for HIV, provision of PMTCT antiretroviral treatment (ART), and the association between HIV infection, birth outcomes and maternal characteristics at the Simão Mendes National Hospital, Guinea-Bissau's largest maternity ward. Among 24,107 women, the HIV prevalence was 3.3% for HIV-1, 0.8% for HIV-2 and 0.9% for HIV-1/2. A significant decline in HIV-1, HIV-2, and HIV-1/2 prevalence was observed over time. HIV infection was associated with age and ethnicity. A total of 85% of HIV-infected women received ART as part of PMTCT, yet overall treatment coverage during labour and delivery declined significantly for both mothers and infants. Twenty-two percent of infants did not receive treatment, and 67% of HIV-2-infected mothers and 77% of their infants received ineffective non-nucleoside reverse transcriptase inhibitors for PMTCT. Maternal HIV was associated with low birth weight but not stillbirth. Inadequate continuity of care and ART coverage present challenges to optimal PMTCT in Guinea-Bissau.

Figure 1

Flow diagram of participants included in the study. The flow diagram displays women included in this study according to HIV status.

Figure 2

Prevalence of HIV-1 and HIV-2 in pregnant women by calendar year, Simão Mendes National Hospital, Bissau, Guinea-Bissau, 2008–2013. The figure displays the changes in HIV-1 (a), HIV-2 (b), and HIV-1/2 (c) prevalence (point estimates and corresponding 95% confidence intervals) among pregnant women presenting for birth by calendar year. HIV-1, HIV-2 and HIV-1/2 all declined significantly from 2009 to 2013 (chi² test for trend).

Figure 3

Self-reported antenatal treatment (a) and treatment provided at birth (b) by calendar year, Simão Mendes National Hospital, Bissau, Guinea-Bissau, 2008–2013. cART combined antiretroviral therapy, AZT Zidovudine, 3TC Lamivudine, sd NVP single-dose Nevirapine. (a) Self-reported treatment regimens received by HIV-positive women presenting for labour by calendar year (N = 566). As shown, the percentage of women receiving AZT prophylaxis increased between 2008 and 2013, while the percentage of women on cART increased slightly from 2008 to 2011 and declined thereafter. (b) The provision of antiretroviral treatment at birth by calendar year, excluding women who reported initiating ART during the antenatal period (N = 774). The figure shows that the proportion of women receiving combined antiretroviral treatment increased steadily between 2009 and 2012, yet the percentage decreased between 2012 and the first quarter of 2013. Conversely, a decline in women receiving option A [AZT prophylaxis + (AZT + 3TC and sd NVP at labour)] between 2008 and 2013 was observed. Women receiving only sd NVP declined notably, suggesting that more women were initiated on treatment before labour. During the same period, we observed a notable increase in the number of HIV-infected women not receiving treatment at delivery. The p values shown were estimated using the chi² test for trend.

Figure 4

The provision of antiretroviral treatment for all HIV-infected women by calendar year, Simão Mendes National Hospital, Bissau, Guinea-Bissau, 2008–2013. cART combined antiretroviral therapy, AZT Zidovudine, 3TC Lamivudine, sd NVP single-dose Nevirapine. The figure displays the provision of antiretroviral treatment at birth by calendar year for all HIV women in this study (N = 1,232). Overall coverage for cART and option A (AZT + 3TC + sd NVP) remained relatively low throughout the study period. There was a decline in the number of women receiving sd NVP, while the overall number of women not receiving any treatment increased over time. The p value shown was estimated using the chi² test for trend.