- Chromosome 13, trisomy 13 complete
- Complete trisomy 13 syndrome
- D trisomy syndrome (formerly)
- Patau syndrome
Your QuestionI previously had a pregnancy affected by trisomy 13. What is the chance of this happening again in a future pregnancy? Should my partner and I get checked for anything in particular?
We have identified the following information that we hope you find helpful. If you still have questions, please contact us.
Questions on this page
- What causes trisomy 13?
- If a previous pregnancy was affected by trisomy 13, what is the chance of having another pregnancy affected with this condition?
- What testing might be available for someone who had a previous pregnancy affected by trisomy 13?
- How can I find a genetics professional in my area?
Trisomy 13 can also occur when part of chromosome 13 becomes attached (translocated) to another chromosome during the formation of reproductive cells (eggs and sperm) or very early in fetal development. This is referred to as translocation trisomy 13. Individuals with this type have two normal copies of chromosome 13, plus an extra copy of chromosome 13 attached to another chromosome.
In rare cases, only part of chromosome 13 is present in three copies in each cell; this is called partial trisomy 13. In other rare cases, a person has an extra copy of chromosome 13 in only some of the body's cells; this is called mosaic trisomy 13. The severity of mosaic trisomy 13 depends on the type and number of cells that have the extra chromosome.
One study estimated that there is a 3 in 1000 chance for women who have had a pregnancy affected by trisomy 13 to have a second pregnancy affected by trisomy 13; there is also approximately a 9 in 1000 chance for a future pregnancy to be affected by trisomy of another chromosome, such as trisomy 21 or trisomy 18. Due to these risks, a woman who has had a pregnancy affected by trisomy 13 should discuss this diagnosis with her personal physicians and should be followed closely during any future pregnancies.
Prenatal testing (such as maternal blood screening, fetal ultrasound, chorionic villus sampling, or amniocentesis) is available to determine if a current pregnancy is at risk for or is affected by trisomy 13 or other chromosome disorders. It is important to discuss the benefits, risks, and limitations of these options with one's personal physicians before having these tests.
Genetics clinics are a source of information for individuals and families regarding genetic conditions, treatment, inheritance, and genetic risks to other family members. More information about genetic consultations is available from Genetics Home Reference. To find a genetics clinic, we recommend that you contact your primary healthcare provider for a referral.
The following online resources can help you find a genetics professional in your community:
- GeneTests has a searchable directory of US and international genetics and prenatal diagnosis clinics.
- The National Society of Genetic Counselors provides a searchable directory of US and international genetic counseling services.
- The American College of Medical Genetics has a searchable database of US genetics clinics.
- The University of Kansas Medical Center provides a list of US and international genetic centers, clinics, and departments.
- The American Society of Human Genetics maintains a database of its members, which includes individuals who live outside of the United States. Visit the link to obtain a list of the geneticists in your country, some of whom may be researchers that do not provide medical care.
- Trisomy 13. Genetics Home Reference. January 2009; http://ghr.nlm.nih.gov/condition/trisomy-13. Accessed 2/2/2011.
- Warburton D, Dallaire L, Thangavelu M, Ross L, Levin B, Kline J. Trisomy recurrence: a reconsideration based on North American data. American Journal of Medical Genetics. 2004; 75:376-385. http://www.ncbi.nlm.nih.gov/pubmed/15248154. Accessed 4/15/2012.
- De Souza E, Halliday J, Chan A, Bower C, Morris JK. Recurrence risks for trisomies 13, 18, and 21. American Journal of Medical Genetics Part A. 2009; 149A:2716-2722. http://www.ncbi.nlm.nih.gov/pubmed/19921649. Accessed 4/10/2012.