Effect of administration of antihelminthics for soil transmitted helminths during pregnancy

Helminthiasis is infestation of the human body with parasitic worms and it is estimated to affect 44 million pregnancies, globally, each year. Intestinal helminthiasis is associated with blood loss and decreased supply of nutrients for erythropoiesis, resulting in iron deficiency anaemia. Over 50% of the pregnant women in low- and middle-income countries suffer from iron deficiency anaemia. Though iron deficiency anaemia is multifactorial, hook worm infestation is a major contributory cause in women of reproductive age in endemic areas. Antihelminthics are highly efficacious in treating hook worm but evidence of their beneficial effect and safety, when given during pregnancy, has not been established.

To determine the effects of administration of antihelminthics for soil transmitted helminths during the second or third trimester of pregnancy on maternal anaemia and pregnancy outcomes.

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (September 2008).

All prospective randomised controlled trials evaluating the effect of administration of antihelminthics during the second or third trimester of pregnancy.

Two review authors independently assessed trial quality and extracted the data.

Three studies (1329 women) were included in this review. Analysis showed that administration of a single dose of antihelminth in the second trimester of pregnancy is not associated with any impact on maternal anaemia in the third trimester (risk ratio (RR) 0.90; 95% confidence interval (CI) 0.68 to 1.19, random effects (2 studies, n = 1075)). Subgroup analysis on the basis of co-interventions other than antihelminthics which included iron supplementation given to both groups in the study by Larocque et al, and a subset of the study by Torlesse et al, showed that a single dose of antihelminth along with iron supplementation throughout the second and third trimester of pregnancy was not associated with any impact on maternal anaemia in the third trimester as compared to iron supplementation alone (RR 0.76; 95% CI 0.39 to 1.45, random-effects (2 studies, n = 1017)). No impact was found for the outcomes of low birthweight (RR 0.94; 95% CI 0.61 to 1.42 (1study; n = 950)), perinatal mortality (RR 1.10; 95% CI 0.55 to 2.22 (2 studies, n = 1089)) and preterm birth (RR 0.85; 95% CI 0.38 to 1.87 (1 study, n = 984)). Impact on infant survival at six months of age could not be evaluated because no data were available.

The evidence to date is insufficient to recommend use of antihelminthics for pregnant women after the first trimester of pregnancy. More well-designed, large scale randomised controlled trials are needed to establish the benefit of antihelminthic treatment during pregnancy.