Factors associated with birthweight and adverse pregnancy outcomes among children in rural Guinea-Bissau - a prospective observational study.

BACKGROUND: Low birthweight (LBW) is associated with higher mortality and morbidity, but there is limited data on the prevalence of LBW in rural Africa, where many births occur at home. The Bacillus Calmette-Guérin (BCG) vaccine has non-specific effects. Studies suggest that maternal BCG-vaccination may affect the health of the child. METHODS: The present study is nested within a randomised trial in rural Guinea-Bissau: Pregnancies were registered at two-monthly village visits, where information on BCG scar status and other background factors were obtained. Children were enrolled in the trial and weighed at home within 72 h after birth. In this prospective observational study, we assessed factors associated with adverse pregnancy outcomes and birthweight in binomial and linear regression models. RESULTS: Among 1320 women who had their BCG scar status assessed, 848 (64%) had a scar, 472 (36%) had no scar. The risk of adverse pregnancy outcomes (miscarriages, stillbirths, early neonatal deaths) tended to be higher among BCG scar-negative women (13%) than among women with a BCG scar (10%), adjusted prevalence ratio = 1.29 (0.99-1.68). Birthweight was assessed for 628 (50%) of the 1232 live born children. The mean birthweight was 2.89 kg (SD 0.43) and the proportion of LBW children was 17% (104/628). Sex, twinning, region of birth, maternal age, maternal mid-upper arm circumference (MUAC), antenatal consultations, parity and possession of a mobile phone were associated with birthweight, while maternal BCG scar status was not. CONCLUSIONS: This study provides the first birthweight data for home-born children in rural Guinea-Bissau, with a mean birthweight of 2.89 kg (SD 0.43) and a LBW prevalence of 17%. We found a tendency for higher risk of adverse pregnancy outcomes among BCG scar-negative women. Birthweight was similar in children of mothers with and without BCG scar.

Can earlier BCG vaccination reduce early infant mortality? Study protocol for a cluster randomised trial in Guinea-Bissau.

INTRODUCTION: The BCG vaccine is designed to protect against tuberculosis, but the vaccine may have broader effects. In 2014, the Strategic Advisory Group of Experts on Immunization reviewed the literature on non-specific effects of BCG, and concluded that the evidence was consistent with beneficial non-specific effects and requested further randomised trials. METHODS AND ANALYSES: Within the Bandim Health Project's urban and rural health and demographic surveillance systems, we will conduct a cluster-randomised trial in six suburban districts and 55 rural villages. Infants are enrolled at a home visit before 72 hours of life. In intervention clusters, children are vaccinated with BCG and oral polio vaccine (OPV). In control clusters, the caregivers are informed about vaccination opportunities. Using Cox-proportional hazards models, we will test whether BCG and OPV provided at a single home visit can reduce early infant mortality up to 60 days.The trial was initiated with a pilot study in Biombo region in June 2015. The trial was scaled up to full study including Oio and Cacheu regions in July 2016. The trial was expanded to include the urban study area in July 2017. ETHICS AND DISSEMINATION: BCG vaccination is delayed in many low-income settings. WHO-recommended home visits are resource demanding and vaccines are not part of the recommendation. Utilising the home visits to provide BCG and OPV may provide countries with a further incentive to introduce a single home visit. In countries, where home visits are already in place, vaccines can easily be added to reduce early infant mortality. The trial is approved by the Guinean Ethical Committee (Reference number: 0016/CNES/INASA/2015) and the Danish Ethics Committee has given its consultative approval. The results of the trial will be published in international peer-reviewed journals. TRIAL REGISTRATION NUMBER: NCT02504203; Pre-results.