What is the reference range for Immunoglobulin M (IgM) in infants?

Medical Advisory BoardAll articles are reviewed for accuracy by our Medical Advisory Board
Educational purpose only • Exercise caution as content is pending human review
Article Review Status
Submitted
Under Review
Approved

Last updated: June 26, 2025View editorial policy

Personalize

Help us tailor your experience

Which best describes you? Your choice helps us use language that's most understandable for you.

From the Guidelines

The reference range for Immunoglobulin M (IgM) in infants is not explicitly stated in the provided evidence, but based on general medical knowledge, IgM levels in newborns typically range from 5-30 mg/dL (0.05-0.3 g/L) at birth and gradually increase during the first year of life. According to the study 1, the focus is on the diagnosis and management of primary immunodeficiency, and while it discusses various aspects of immunoglobulin levels, including IgG and IgA, it does not provide specific reference ranges for IgM in infants. However, it's known that IgM levels are important for diagnosing congenital infections and immunodeficiency, and laboratory reference ranges may vary between institutions. Some key points to consider when interpreting IgM levels in infants include:

  • Newborns have IgM levels that do not cross the placenta, making them useful for diagnosing congenital infections
  • Elevated IgM at birth may indicate intrauterine infection
  • Persistently low IgM levels might suggest immunodeficiency
  • IgM levels continue to increase throughout childhood until reaching adult levels around 4-5 years of age It's essential to refer to the specific reference ranges provided by the testing laboratory when interpreting IgM levels in infants, as these can vary slightly between institutions.

From the Research

Reference Range for Immunoglobulin M (IgM) in Infants

The reference range for IgM in infants is not explicitly stated in the provided studies. However, some studies provide information on IgM levels in infants:

  • A study from 2018 2 generated pediatric reference ranges for IgG, IgA, IgM, IgD, and other immune system components, but it does not provide specific reference ranges for IgM in infants.
  • A study from 2016 3 aimed to determine serum IgG and IgM levels in preterm and term newborns, but it does not provide a clear reference range for IgM in infants.
  • Other studies 4, 5, 6 focus on the use of IgM as a screening test for congenital infections or the recognition of specific antigens by IgM antibodies, but they do not provide reference ranges for IgM in infants.

Key Findings

  • IgM levels remain stable across different age groups, according to the 2018 study 2.
  • Preterm babies appear to have lower IgM levels, which may carry the risk of relevant morbidity, as stated in the 2016 study 3.
  • The measurement of IgM can be useful in the diagnosis of congenital infections, as shown in studies from 1994 4 and 1988 6.

IgM Levels in Infants

  • The 2016 study 3 found that serum IgM levels increase with gestational age and birth weight.
  • However, the study does not provide a specific reference range for IgM in infants.
  • More research is needed to establish a clear reference range for IgM in infants.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Reference values of serum IgG and IgM levels in preterm and term newborns.

The journal of maternal-fetal & neonatal medicine : the official journal of the European Association of Perinatal Medicine, the Federation of Asia and Oceania Perinatal Societies, the International Society of Perinatal Obstetricians, 2016

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

Have a follow-up question?

Our Medical A.I. is used by practicing medical doctors at top research institutions around the world. Ask any follow up question and get world-class guideline-backed answers instantly.