Chromosome Screening
Prenatal screening can tell you the chance for a baby to have trisomy 21 (Down syndrome) or trisomy 18 (Edwards syndrome). There is no risk to the pregnancy because it is done by bloodwork and ultrasound. Some of the screening options below can screen for other chromosome differences, including trisomy 13 (Patau syndrome) and sex chromosome differences.
For Health-Care Providers
Requisitions
What are Chromosome Differences?
Chromosome differences are caused by having extra or missing chromosomes. These differences can affect a baby’s development, learning, and health in different ways, and the impact can vary widely from person to person.
Screening for twins or more than two babies
Read about the screening options available to individuals expecting twins or more than two babies.
Screening for vanishing twins
If your pregnancy started as a twin pregnancy and one twin miscarried, this is sometimes called a "vanishing" twin pregnancy. Read about screening options available.
For Health-Care Providers
Office Guide to Prenatal Screening Options for Chromosome Differences
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Virtual educational sessions on prenatal screening and nuchal translucency quality assurance are available upon request for health‑care providers.