Seroepidemiological survey of cytomegalovirus infection among pregnant women in Nagasaki, Japan

Pediatr Int. 2010 Jun;52(3):459-62. doi: 10.1111/j.1442-200X.2009.03005.x. Epub 2009 Nov 16.


Background: Epidemiology of cytomegalovirus (CMV) infection varies widely, depending on ethnicity and socioeconomic status. A seroepidemiological survey was conducted to determine CMV infection among pregnant women in Nagasaki Prefecture, Japan.

Methods: We measured serum CMV-specific immunoglobulin (Ig) M and IgG at the first and third trimesters. IgG avidity was determined when both CMV-IgG and CMV-IgM were positive.

Results: Of 339 pregnant women, 296 (87.3%) were CMV-IgG-positive at the first trimester. Of 267 paired sera, one (0.37%) had CMV-IgG seroconversion, another one (0.37%) had CMV-IgM seroconversion, and 12 had both CMV-IgG and CMV-IgM, two (0.75%) of whom had low IgG avidity, suggesting recent infection. Thus, the incidence of primary CMV infection during pregnancy was 0.74-1.5%. Assuming the rate of in utero transmission following maternal primary infection to be approximately 40%, the incidence of congenital infection is estimated to be 0.3-0.6%.

Conclusion: Although CMV seroprevalence among pregnant women has been decreasing in industrialized regions including other parts of Japan, CMV-seroprevalence remains high in Nagasaki. Thus, epidemiology of CMV infection seems variable within Japan, a country generally considered to be ethnically and socioeconomically homogeneous. However, 40-80 infants may be congenitally infected and 15-27% (or 6-22) of them may ultimately suffer from certain neurological sequelae annually in Nagasaki Prefecture, so where annual live births are approximately 13,300, congenital CMV infection seems to be a significant public health problem in such an apparently low-risk region as Nagasaki.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Age Distribution
  • Cytomegalovirus / immunology*
  • Cytomegalovirus / isolation & purification
  • Cytomegalovirus Infections / diagnosis
  • Cytomegalovirus Infections / epidemiology*
  • Female
  • Health Surveys
  • Humans
  • Immunoglobulin G / blood*
  • Immunoglobulin M / blood*
  • Japan / epidemiology
  • Pregnancy
  • Pregnancy Complications, Infectious / diagnosis
  • Pregnancy Complications, Infectious / epidemiology*
  • Pregnancy Outcome*
  • Pregnancy Trimester, First
  • Pregnancy Trimester, Third
  • Prevalence
  • Seroepidemiologic Studies
  • Severity of Illness Index
  • Urban Population
  • Young Adult


  • Immunoglobulin G
  • Immunoglobulin M