Malaria in Pregnancy Before and After the Implementation of a National IPTp Program in Gabon

Michael Ramharter 0 1 2 Katharina Schuster 0 1 2 Marielle K. Bouyou-Akotet 0 1 2 Ayola A. Adegnika 0 1 2 Kristen Schmits 0 1 2 Ghyslain Mombo-Ngoma 0 1 2 Selidji T. Agnandji 0 1 2 Johannes Nemeth 0 1 2 Solange Nzenze Afne 0 1 2 Saadou Issifou 0 1 2 Isabelle Ndombi Onnas 0 1 2 Maryvonne Kombila 0 1 2 Peter G. Kremsner 0 1 2 0 Internal Medicine 1, Division of Infectious Diseases, Medical Uni- versity of Vienna , Vienna , Austria 1 Medical Research Unit, Albert Schweitzer Hospital , Lambarene , Gabon; Institut Pasteur, Universite de la Mediterranee , Marseille , France; Department of Medicine I, Division of Infectious Diseases and Tropical Medicine, Medical University of Vienna , Vienna , Austria ; Institute for Tropical Medicine, Department for Parasitology, University of Tubingen, Tubingen, Germany; Departement de Parasitologie, Mycologie, Medecine Tropicale, Universite des Sciences de la Sante, Libreville, Gabon; Departement de Maternite, Centre Hospitalier de Libreville , Libreville , Gabon 2 Authors' addresses: Michael Ramharter, Katharina Schuster, Ayola A. Adegnika , Kristen Schmits, Ghyslain Mombo-Ngoma, Selidji T. Agnandji, Johannes Nemeth, Saadou Issifou, and Peter G. Kremsner , Medical Research Unit, Albert Schweitzer Hospital , Lambarene, Ga- bon, Telephone: 3 43 14 04 004 418. Michael Ramharter, Katharina Schuster, Ayola A. Adegnika, Ghys- lain Mombo-Ngoma, Selidji T. Agnandji, Johannes Nemeth, Saadou Issifou, and Peter G. Kremsner, Institute for Tropical Medicine, De- partment for Parasitology, University of Tubingen, Tubingen, Ger- many. Marielle K. Bouyou-Akotet, Solange Nzenze Afene, and Maryvonne Kombila, Departement de Parasitologie , Mycologie, Me- decine Tropicale , Universite des Sciences de la Sante, Libreville, Ga- bon. Isabelle Ndombi Onnas, Departement de Maternite, Centre Hospitalier de Libreville , Libreville , Gabon Intermittent preventive treatment in pregnancy (IPTp) with sulfadoxine-pyrimethamine has recently been adopted by many African countries to reduce maternal and neonatal morbidity and mortality associated with malaria in pregnancy. We assessed the impact of a newly established national IPTp program on maternal and neonatal health in Gabon. Data on prevalence of maternal Plasmodium falciparum infection, anemia, premature birth, and birth weight were collected in cross-sectional surveys in urban and rural regions of Gabon before and after the implementation of IPTp in a total of 1403 women and their offspring. After introduction of IPTp, the prevalence of maternal Plasmodium falciparum infection decreased dramatically (risk ratio 0.16, P < 0.001). Whereas only a modest effect on the rate of anemia in pregnant women was observed, there was a marked benefit on the prevalence of low birth weight and premature birth for women adhering to national recommendations. These effects were most pronounced in primi- and secundigravid women. - Malaria in pregnancy causes considerable morbidity and mortality in pregnant women and newborns in sub-Saharan Africa.1 The World Health Organization recommends a three-pronged approach to tackle malaria in pregnancy based on the implementation of impregnated bed nets, effective case management of clinical disease, and intermittent preventive treatment in pregnancy (IPTp) with sulfadoxine pyrimethamine.2,3 The recommendation of IPTp was initially based on several studies conducted in East and South-East Africa demonstrating beneficial effects on the prevalence of maternal anemia and low birth weight.47 This benefit was most pronounced for nulli- and primiparous women living in high-transmission regions. Epidemiologic variations and parity of pregnant women may therefore significantly influence the overall risk/benefit analysis for regional IPTp programs.8,9 Since the World Health Organization has recommended the use of IPTp in sub-Saharan Africa, several countries have adopted this strategy for the prevention of malaria in pregnancy.3 Whereas several clinical trials evaluating IPTp regimens in Africa have been conducted recently, there is a lack of data on the impact of national IPTp programs under realworld conditions in Central Africa. The central African country Gabon implemented a nationwide IPTp program in 2005. This program aims at providing two doses of sulfadoxinepyrimethamine as presumptive treatment of all pregnant women free of charge.10 Based on data from a cross-sectional survey of pregnancy-associated malaria in the period before the implementation of IPTp in Gabon (2003/2004), we conducted a re-assessment after the full implementation of IPTp in 2005/2006. The aim of this work was to provide epidemiologic evidence of whether implementation of the IPTp in Gabon led to a favorable risk/ benefit analysis for maternal and neonatal health in Gabon. MATERIALS AND METHODS This study consists of two cross-sectional surveys conducted from May 2003 to February 2004 and from May 2005 to September 2006 (subsequently referred to as survey 2004 and survey 2006). Both surveys took place in obstetrics departments of local hospitals in the cities of Libreville (Center Hospitalier de Libreville) and Lambarn (Hpital Rgional de Lambarn and Albert Schweitzer Hospital) in the central African country Gabon. Libreville, the capital of Gabon, is a typical urban region, with the surrounding region home to approximately half of the countrys total population, currently estimated at 1.2 million. Lambarn is a small city 250 km southeast of Libreville located in the province MoyenOgoou. Lambarn is characterized by a rural setting. Both regions are characterized by stable perennial malaria transmission and Plasmodium falciparum highly resistant to chloroquine.11 HIV prevalence in adults (of age 1549 years) was estimated at 7.9% in 2005.12 Women attending the hospital for delivery were invited to participate in this survey. Informed consent was sought from the mother and the guardian accompanying the patient to the hospital. The study protocol was approved by the Ethics Committee of the International Foundation for the Albert Schweitzer Hospital in Lambarn. An investigator obtained necessary information from the motherchild health booklet and performed a structured interview. A thick blood smear was performed according to the Lambarn method,13 and hemoglobin measurements of capillary blood were performed in a subgroup of participants.13 Definitions. Gestational age was calculated based on information on last date of menses. Birth weight of the newborn was recorded ( 5 g) immediately after delivery. Deliveries before week 37 of gestation were classified as premature. Anemia was stratified as moderate (< 11 g/dL) and severe (< 8 g/dL). Threshold levels for low birth weight and very low birth weight were defined as < 2500 and < 1500 g, respectively. Participants were stratified in two groups depending on adherence to IPTp recommendations for respective analysis (no IPTp administration during pregnancy, No IPTp group; an (...truncated)