Asymptomatic malaria parasitaemia in pregnant women at booking in a primary health care facility in a periurban community in Lagos, Nigeria.

Malaria can cause severe disease in pregnancy. We determined asymptomatic parasitaemia in 477 consenting consecutive women during their booking visits to a primary health care facility in a peri-urban area in Lagos State. There were 129 primigravidae and 348 multigravidae, with mean ages of 19.8 +/- 2.4 years (range 16-26 years) and 25.7 +/- 3.7 years (range 19-41 years), respectively. Most of the patients, 77.5% of primigravidae and 73.6% of multigravidae booked in the second trimester. Many (79.1%) of the primigravidae and 81.9% of the multigravidae had not taken any form of antimalaria chemoprophylaxis at the time of booking. Parasitaemia was significantly higher in the primigravidae than in the multigravidae 44.2% vs 33.6% (chi2 = 3.89, P < 0.05). In both primigravidae and multigravidae parasitaemia was highest in the second trimester compared with the two other trimesters (chi2 = 7.92, P < 0.02 and chi2 = 8.54, P < 0.01, respectively). There was no significant difference in parasitaemia among those who had anti-malaria chemoprophylaxis prior to booking and those who did not (P > 0.05). Prevalence of anaemia (PCV < 33%) was high, 73.6% in primigravidae and 69.8% in multigravidae, severe anaemia (PCV < 21%) however, was significantly associated with parasitaemia in the primigravidae (chi2 = 115, P < 0.001). Asymptomatic malaria parasitaemia at booking is high, hence we recommend parasites clearance in all patients at booking.