Open Peer Review Any reports and responses or comments on the article can be found at the end of the article. RESEARCH ARTICLE Leptin, insulin like growth factor-I levels and histology-diagnosed placental malaria in an area characterized by unstable malaria transmission in central Sudan [version 1; peer review: 2 approved with reservations] Hagir Elsheikh , Ishag Adam , Elhassan M. Elhassan , Ahmed A. Mohammed , Ammar H. Khamis , Mustafa I. Elbashir 2 Faculty of Pharmacy, University of Khartoum, Khartoum, Sudan Faculty of Medicine, University of Khartoum, Khartoum, Sudan Faculty of Medicine, University of Geziera, Medani, Sudan Faculty of Medicine, Ribat University, Khartoum, Sudan College of Medicine, Mohammed Bin Rashid University Of Medicine and Health Sciences (MBRU), Dubai, United Arab Emirates Abstract Background: There are few published data on the association between leptin, insulin like growth factor-1 (IGF-1) and malaria during pregnancy. This study aimed to investigate maternal and umbilical cord leptin and IGF-1 levels and malaria during pregnancy, and their association - if any - with birth weight. Methods: A cross-sectional study was conducted at Medani, Sudan. Medical and obstetrics history was gathered from each parturient woman (n=175) and malaria was investigated by blood film and placental histology. Maternal and umbilical cord leptin and IGF-1 levels were measured using ELISA. Results: Upon histological examination, 48 women were infected with placental malaria, and 127 were found free from the disease. Out of the 48, 2 of the patients showed signs of active infection, 3 of chronic infection and 43 of previous infection. Placental malaria and preterm delivery were associated with low birth weight (< 2500 g). Younger mothers and primigravidae had a higher risk for placental malaria infection. There was no significant difference in maternal and umbilical cord leptin and IGF-1 levels between women infected with placental malaria and those free from the disease. Conclusions: The current study showed that low birth weight was significantly associated with placental malaria. Young mothers and primigravidae had a higher risk to develop the infection. There was no significant difference in the levels of maternal and umbilical cord leptin and IGF-1 levels between women infected with placental malaria and those free from the disease. Both the levels of maternal and cord leptin and IGF-1were found not to be associated with birth weight. 1 2 3 4 2,5 2 1 2 3 4 5 Reviewer Status Invited Reviewers version 1 published 22 May 2017 1 2 report report , Muhimbili University of Edward Kabyemela Health and Allied Sciences, Dar es Salaam, Tanzania 1 , Harvard T.H. Chan School Chloe R. McDonald of Public Health, Boston, USA 2 22 May 2017, :736 ( First published: 6 ) https://doi.org/10.12688/f1000research.10641.1 22 May 2017, :736 ( Latest published: 6 ) https://doi.org/10.12688/f1000research.10641.1 v1 Page 1 of 17 F1000Research 2017, 6:736 Last updated: 02 DEC 2019