[1] CISM, Rua 12, Manhica 1121, Mozambique
[2] UEM, Dept Obstet & Gynaecol, Fac Med, Ave Agostinho Neto 679, Maputo 1100, Mozambique
[3] Uppsala Univ, Dept Womens & Childrens Hlth, Womens & Childrens Hlth, Akad Sjukhuset, SE-75185 Uppsala, Sweden
[4] Karolinska Inst, Dept Publ Hlth Sci, Tomtebodavagen 18A,Plan 4, Stockholm, Sweden
[5] London Sch Hyg & Trop Med, Dept Dis Control, Keppel St, London WC1E 7HT, England
[6] UCL, Inst Global Hlth, Gower St, London WC1E 6BT, England
[7] UEM, Fac Med, Dept Physiol Sci, Clin Pharmacol, Ave Salvador Allende 702 R-C, Maputo, Mozambique
[8] UEM, Fac Med, Dept Community Hlth, Ave Salvador Allende 702 R-C, Maputo, Mozambique