Test Catalog

Test ID: MATCC    
Maternal Cell Contamination, Molecular Analysis, Varies

Useful For Suggests clinical disorders or settings where the test may be helpful

Ruling out the presence of maternal cell contamination within a fetal specimen


This test is required for all prenatal testing performed in Mayo's molecular and biochemical genetics laboratories

Genetics Test Information Provides information that may help with selection of the correct genetic test or proper submission of the test request

Required in conjunction with molecular and biochemical prenatal testing only.

Testing Algorithm Delineates situations when tests are added to the initial order. This includes reflex and additional tests.

For prenatal specimens only: If amniotic fluid (nonconfluent cultured cells) is received, amniotic fluid culture/genetic test will be added and charged separately. If chorionic villus specimen (nonconfluent cultured cells) is received, fibroblast culture for genetic test will be added and charged separately.


If this test is ordered in conjunction with CMAP / Chromosomal Microarray, Prenatal, Amniotic Fluid/Chorionic Villus Sampling or CMAPC / Chromosomal Microarray, Autopsy, Products of Conception, or Stillbirth, and no other molecular testing is ordered, test will be changed to PPAP / Parental Sample Prep for Prenatal Microarray Testing.

Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test

One of the risks associated with prenatal testing is maternal cell contamination (MCC), which can occur when a fetal specimen comes into contact with maternal blood or tissue. The risk of MCC is associated with procedures such as chorionic villus sampling, amniocentesis, or extraction of fetal blood from the umbilical cord (cord blood). If MCC is present, the maternal DNA may mask the results of any genetic testing performed on the fetal DNA. Therefore, the results of prenatal testing may be compromised.


To rule out the presence of MCC, a maternal blood specimen is necessary for comparison of maternal and fetal chromosomal markers. The presence of both maternal and nonmaternal alleles for each fetal marker indicates the fetal specimen is not contaminated. MCC is confirmed when both alleles in the fetus are maternal.

Reference Values Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.

An interpretative report will be provided.

Interpretation Provides information to assist in interpretation of the test results

An interpretive report will be provided.

Cautions Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances

This test does not rule out the presence of low-level maternal cell contamination (<5%).

Clinical Reference Recommendations for in-depth reading of a clinical nature

Nagan N, Faulkner NE, Curtis C, et al: Laboratory guidelines for detection, interpretation, and reporting of maternal cell contamination in prenatal analyses a report of the association for molecular pathology. J Mol Diagn 2011 Jan;13(1):7-11

Special Instructions Library of PDFs including pertinent information and forms related to the test