Maternal malaria, birth size and blood pressure in Nigerian newborns: insights into the developmental origins of hypertension from the Ibadan growth cohort

• Published in: PloS one Vol. 6; no. 9; p. e24548
• Main Authors: Ayoola, Omolola O, Gemmell, Isla, Omotade, Olayemi O, Adeyanju, Olusoji A, Cruickshank, J Kennedy, Clayton, Peter Ellis
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 13-09-2011; Public Library of Science (PLoS)
• Subjects: Adolescent; Adult; Age; Anemia; Anthropometry; Anthropometry - methods; Babies; Birth Weight; Blood; Blood Pressure; Childbirth & labor; Children & youth; Chronic illnesses; Cohort Studies; Ethics; Female; Fetal development; Fetuses; Growth; Health sciences; Hematocrit; Hospitals; Humans; Hypertension; Hypertension - complications; Hypotheses; Malaria; Male; Maternal Exposure; Measurement methods; Medicine; Middle Aged; Neonates; Newborn babies; Newborn infants; Nigeria; Parasites; Plasmodium falciparum; Pregnancy; Pregnancy Complications, Cardiovascular - diagnosis; Pregnancy Complications, Parasitic - diagnosis; Pregnant women; Prenatal experience; Vector-borne diseases; Womens health; Nigeria; United Kingdom > UK
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0024548

Hypertension is an increasing health issue in sub-Saharan Africa where malaria remains common in pregnancy. We established a birth cohort in Nigeria to evaluate the early impact of maternal malaria on newborn blood pressure (BP).
Anthropometric measurements, BP, blood films for malaria parasites and haematocrit were obtained in 436 mother-baby pairs. Women were grouped to distinguish between the timing of malaria parasitaemia as 'No Malaria', 'Malaria during pregnancy only' or 'Malaria at delivery', and parasite density as low (<1000 parasites/µl of blood) and high (≥ 1000/µl).
Prevalence of maternal malaria parasitaemia was 48%, associated with younger maternal age (p<0.001), being primigravid (p = 0.022), lower haematocrit (p = 0.028). High parasite density through pregnancy had the largest effect on mean birth indices so that weight, length, head and mid-upper arm circumferences were smaller by 300 g, 1.1 cm, 0.7 cm and 0.4 cm respectively compared with 'No malaria' (all p ≤ 0.005). In babies of mothers who had 'malaria at delivery', their SBPs adjusted for other confounders were lower respectively by 4.3 and 5.7 mmHg/kg compared with 'malaria during pregnancy only' or 'none'. In contrast the mean newborn systolic (SBP) and diastolic BPs (DBP) adjusted for birth weight were higher by 1.7 and 1.4 mmHg/kg respectively in babies whose mothers had high compared with low parasitaemia.
As expected, prenatal malarial exposure had a significant impact on fetal growth rates. Malaria at delivery was associated with the lowest newborn BPs while malaria through pregnancy, which may attenuate growth of the vascular network, generated higher newborn BPs adjusted for size. These neonatal findings have potential implications for cardiovascular health in sub-Saharan Africa.