Malaria Parasitaemia among Pregnant Women Attending Antenatal Care in Minna, Nigeria: A Historical Cross-Sectional Study from 2008

Abstract

Background: Malaria remains an important health concern among pregnant women in sub-Saharan Africa, with substantial variation in infection prevalence across populations, locations and diagnostic approaches. Historical data can provide useful epidemiological context for understanding past malaria burden and patterns. However, documented evidence from pregnant women attending antenatal care in Minna, Nigeria, during the earlier period remains limited, warranting analysis of the available 2008 dataset. Aims: To describe the prevalence and distribution of microscopy-detected Plasmodium infection among pregnant women attending antenatal care at Minna General Hospital, Niger State, Nigeria, between May and July 2008, using the surviving historical aggregate data. Study design: Historical cross-sectional design. Place and Duration of Study: Department of Medical Laboratory Science and Antenatal Clinic, Minna General Hospital, Minna, Niger State, Nigeria, between May and July 2008. Methodology: A total of 230 pregnant women were included. Information on malaria positivity, maternal age, gestational trimester, parity and Plasmodium species was retrieved from the subjects. Thick and thin blood films were prepared and stained with Giemsa and examined microscopically. Prevalence estimates were recalculated with 95% Wilson confidence intervals. Pearson chi-square tests were used for unadjusted associations with age group, trimester and parity. Results: Plasmodium parasites were detected in 109/230 women (47.4%, 95% CI 41.0–53.8). Among positive samples, 106 (97.2%) were reported as Plasmodium falciparum and 3 (2.8%) as P. malariae. Positivity did not differ significantly by age group (χ²=6.65, df=4, p=0.155) or parity (χ²=0.21, df=1, p=0.645). Positivity varied across trimester categories (χ²=11.76, df=2, p=0.0028), with prevalence of 54.8% in the first trimester, 56.9% in the second and 33.3% in the third. Conclusion: Microscopy-detected Plasmodium infection was common among the pregnant women represented in this historical Minna dataset in 2008. P. falciparum predominated. The trimester pattern should be interpreted as an unadjusted cross-sectional association rather than evidence of a causal effect of gestational age. These findings are best regarded as a historical reference point rather than a contemporary prevalence estimate.