Skip to Content
Home > Wellness > Health Library > Multiple Pregnancy: Genetic Disorders and Birth Defects
Genetic disorders, such as
Down syndrome or
cystic fibrosis, and birth defects occur more
frequently in multiple pregnancies than in pregnancies with one fetus. A group
of deformities of the ankles and/or feet (clubfoot) is an example of a birth
defect seen more commonly in multiple pregnancy.
disorders and birth defects occur more frequently in identical fetuses than in
fraternal ones. In rare cases, problems occur when the genetic material
(chromosomes) in the fertilized egg does not split evenly. This can result in
severe mental or physical defects in one or more fetuses.
Conjoined (Siamese) twins occur rarely. This occurs when the egg does not
split completely and the fetuses are partially joined.
Most doctors advise pregnant women to be screened for genetic disorders.
Current as of:
June 4, 2014
Sarah Marshall, MD - Family Medicine & William Gilbert, MD - Maternal and Fetal Medicine
How this information was developed to help you make better health decisions.
To learn more, visit Healthwise.org
© 1995-2014 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.
Our interactive Decision Points guide you through making key health decisions by combining medical information with your personal information.
You'll find Decision Points to help you answer questions about:
Get started learning more about your health!
Our Interactive Tools can help you make smart decisions for a healthier life. You'll find personal calculators and tools for health and fitness, lifestyle checkups, and pregnancy.
Feeling under the weather?
Use our interactive symptom checker to evaluate your symptoms and determine appropriate action or treatment.