Impaired uteroplacental blood flow in pregnancies complicated by falciparum malaria

Authors

  • Dr E. K. Dorman,

    Corresponding author
    1. Kenya Medical Research Institute (KEMRI), Centre for Geographical Medicine Research, Coast, Kilifi, Kenya
    2. Department of Obstetrics and Gynaecology, Homerton Hospital, London, UK
    • Department of Obstetrics and Gynaecology, Homerton Hospital, Homerton Row, London E9 6SR, UK
    Search for more papers by this author
  • C. E. Shulman,

    1. Kenya Medical Research Institute (KEMRI), Centre for Geographical Medicine Research, Coast, Kilifi, Kenya
    2. London School of Hygiene and Tropical Medicine, London, UK
    Search for more papers by this author
  • J. Kingdom,

    1. Department of Maternal-Fetal Medicine, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada
    Search for more papers by this author
  • J. N. Bulmer,

    1. Department of Pathology, University of Newcastle, Royal Victoria Infirmary, Newcastle upon Tyne, UK,
    Search for more papers by this author
  • J. Mwendwa,

    1. Kenya Medical Research Institute (KEMRI), Centre for Geographical Medicine Research, Coast, Kilifi, Kenya
    Search for more papers by this author
  • N. Peshu,

    1. Kenya Medical Research Institute (KEMRI), Centre for Geographical Medicine Research, Coast, Kilifi, Kenya
    Search for more papers by this author
  • K. Marsh

    1. Kenya Medical Research Institute (KEMRI), Centre for Geographical Medicine Research, Coast, Kilifi, Kenya
    2. University of Oxford, Institute of Molecular Medicine, John Radcliffe Hospital, Oxford, UK
    Search for more papers by this author

Abstract

Objective

In endemic areas, maternal malaria infection is usually asymptomatic. However, it is known that infected maternal erythrocytes sequester in the intervillous space of the placenta. There is a strong association between placental malaria infection and both low birth weight (LBW) and severe maternal anemia. We aimed to determine whether impaired uteroplacental blood flow might account for the low infant birth weight associated with maternal falciparum malaria infection.

Methods

This observational study was carried out during a large double-blind, randomized, controlled trial of an antimalarial drug intervention for primigravidae. Nine hundred and ninety-five women were recruited from the antenatal clinic at a district hospital on the Kenya coast and had at least one Doppler ultrasound scan. Uterine artery resistance index and the presence or absence of a diastolic notch were recorded. In the third trimester, blood was taken for hemoglobin and malaria film.

Results

Malaria infection at 32–35 weeks of gestation was associated with abnormal uterine artery flow velocity waveforms on the day of blood testing (relative risk (RR) 2.11, 95% confidence interval (CI) 1.24–3.59, P = 0.006). This association persisted after controlling for pre-eclampsia. Impaired uteroplacental blood flow in the women studied was also predictive of poor perinatal outcome, including low birth weight, preterm delivery and perinatal death. The risk of preterm delivery in women with histological evidence of past placental malaria infection was more than twice that of women without infection (RR 2.33, 95% CI 1.31–4.13, P = 0.004).

Conclusions

Uteroplacental hemodynamics are altered in the presence of maternal falciparum malaria infection. This may account for some of the excess of LBW babies observed in malaria endemic areas. Strategies that prevent or clear placental malaria may confer perinatal benefit through preservation of placental function. Copyright © 2002 ISUOG

Ancillary