Risk factors and mechanisms of preterm delivery in Malawi.
OBJECTIVE
We examined risk factors and mechanisms of preterm delivery (PTD) in malaria-exposed pregnant women in Blantyre, Malawi.


METHODS
The human immunodeficiency virus (HIV), malaria, syphilis, and anemia were assessed in a cross-sectional study of 572 pregnant women. In a nested case-control study, chorioamnionitis (CAM) was examined; tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, IL-8, macrophage inflammatory protein (MIP)-1alpha, monocyte chemotactic protein (MCP)-1, transforming growth factor (TGF)-beta, cortisol, and corticotropin-releasing hormone were measured in placental, maternal and/or cord blood.


RESULTS
HIV, infrequent antenatal clinic attendance, low-maternal weight, no intermittent preventive malaria therapy (IPT), and CAM were associated with PTD, while malaria was not. Of the 18 compartmental cytokine measurements, elevations in placental and/or cord IL-6 and IL-8 were associated with both CAM and PTD. In contrast, there was no overlap between the cytokines affected by malaria and those associated with PTD.


CONCLUSIONS
The HIV and CAM were the major infections associated with PTD in this study. CAM, but not malaria, causes PTD via its effect on proinflammatory cytokines.
Department of Anthropology, University of Michigan, Ann Arbor, MI, USA.
Elizabeth T
ET
Abrams
Danny A
DA
Milner
Jesse
J
Kwiek
Victor
V
Mwapasa
Deborah D
DD
Kamwendo
Donglin
D
Zeng
Eyob
E
Tadesse
Valentino M
VM
Lema
Malcolm E
ME
Molyneux
Stephen J
SJ
Rogerson
Steven R
SR
Meshnick
D000740:Anemia / Q000453:epidemiology; D016022:Case-Control Studies; D018925:Chemokines / Q000378:metabolism; D002821:Chorioamnionitis / Q000453:epidemiology; D016207:Cytokines / Q000378:metabolism; D005260:Female; D015658:HIV Infections / Q000453:epidemiology; D006801:Humans; D008288:Malaria / Q000453:epidemiology*; D008295:Malawi; D011247:Pregnancy; D047928:Premature Birth / Q000453:epidemiology* / Q000378:metabolism; D012307:Risk Factors
D018925:Chemokines; D016207:Cytokines