Helicobacter pylori infection and Hyperemesis gravidarum. An institution-based case-control study

Eur J Epidemiol. 2008;23(7):491-8. doi: 10.1007/s10654-008-9261-3. Epub 2008 May 21.


Background: The etiology of Hyperemesis gravidarum (HG) is unclear. To test the hypothesis of an association between Helicobacter pylori infection and HG, an institution-based case-control study was performed at Aker University Hospital (AUH) during 1994-1999.

Material and method: From the same source population, 244 incident cases of HG and 244 pregnant women free of the disease (controls) were consecutively identified.

Results: H. pylori were noted in 105 cases and 58 control subjects. The presence of H. pylori increased the risk of HG more than two fold (OR = 2.42, 95% CI: 1.64-3.57, P < 0.001). This association was much stronger in Africans as compared to non-Africans (OR = 5.26, 95% CI: 1.04-26.57 vs. OR = 1.67, 95% CI: 1.07-2.61) after controlling for the confounding effect of maternal age. A gradient effect of exposure to H. pylori, determined by presence of specific IgG antibody in serum, and increased frequency of HG was present in Africans (test for linear trend P = 0.05) and non-Africans (test for linear trend P = 0.004).

Conclusion: These results indicate that H. pylori increase the risk of HG with a dose-response pattern and stronger in Africans.

MeSH terms

  • Adolescent
  • Adult
  • African Continental Ancestry Group*
  • Case-Control Studies
  • Female
  • Helicobacter Infections / complications*
  • Helicobacter Infections / epidemiology
  • Helicobacter pylori*
  • Hospitals, University / statistics & numerical data
  • Humans
  • Hyperemesis Gravidarum / epidemiology
  • Hyperemesis Gravidarum / ethnology*
  • Hyperemesis Gravidarum / microbiology*
  • Incidence
  • Norway / epidemiology
  • Odds Ratio
  • Pregnancy
  • Prevalence