Failure of chloroquine malaria prophylaxis in pregnancy.

Women in a hyperendemic malarious area of Papua New Guinea are supplied with weekly chloroquine chemoprophylaxis at antenatal clinics. A study of 180 women in late pregnancy failed to show any difference in Plasmodium falciparum parasite rates between regular and irregular clinic attenders. Nor was anaemia in late pregnancy associated with parasitaemia; however, grandmultiparas exhibited significantly more prevalent parasitaemia and anaemia in late pregnancy. This study reveals a need for a more detailed investigation of the effects and usefulness of chemoprophylaxis with chloroquine in areas where P. falciparum chloroquine resistance is present.