Trichuris and hookworm infections associated with anaemia during pregnancy

Trop Med Int Health. 2011 Apr;16(4):531-7. doi: 10.1111/j.1365-3156.2011.02727.x. Epub 2011 Feb 1.


Objective: To assess the following associations between the second and third trimesters of pregnancy: (i) the intensity of soil-transmitted helminth (STH) infection and haemoglobin/anaemia, (ii) the effect of mebendazole treatment on the occurrence of STH infection, and (iii) the effect of mebendazole treatment on haemoglobin/anaemia.

Methods: Data originated from a trial of 1042 pregnant women recruited in their second trimester and followed to delivery. Baseline assessments included socio-demographic/health information from questionnaires, haemoglobin/anaemia from HemoCue ascertainment of fingerprick blood, and the presence and intensity of STH (Ascaris lumbricoides, hookworms and Trichuris trichiura) infections from Kato-Katz examination. All women were given iron supplements; half were randomly allocated to receive single dose 500 mg mebendazole, and half, placebo. Haemoglobin/anaemia and STH infection status were determined again in the third trimester of pregnancy.

Results: Complete information was available from 935 (89.7%) women. Mebendazole significantly reduced the prevalence and intensity of all three STH infections. Higher intensities of hookworm and Trichuris infections in the second trimester were associated with a higher risk of anaemia in the third trimester. Overall, women with moderate/heavy Trichuris infection were found to be at a higher risk of anaemia; the highest risk was observed among those with moderate/heavy hookworm co-infection (adjusted OR = 2.77; 95% CI: 1.26, 6.11). Mebendazole treatment did not reduce the risk of anaemia.

Conclusion: Higher intensities of both Trichuris and hookworm infections are associated with anaemia in pregnancy. The importance of Trichuris infections during pregnancy requires renewed attention.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Anemia / parasitology*
  • Animals
  • Antinematodal Agents / therapeutic use
  • Ascariasis / complications*
  • Ascariasis / prevention & control
  • Ascaris lumbricoides*
  • Female
  • Hemoglobins / metabolism
  • Humans
  • Mebendazole / therapeutic use
  • Pregnancy
  • Pregnancy Complications, Hematologic / parasitology*
  • Pregnancy Complications, Parasitic / prevention & control*
  • Prenatal Care / methods
  • Socioeconomic Factors
  • Treatment Outcome
  • Trichuriasis / complications*
  • Trichuriasis / prevention & control


  • Antinematodal Agents
  • Hemoglobins
  • Mebendazole