What Is Trisomy 13 OR Patau Syndrome?
It can be extremely difficult to hear that your unborn baby has trisomy 13, also known as Patau Syndrome. You probably have a lot of questions about what caused it and whether or not it can be treated.
What is Trisomy 13?
Trisomy 13 is a genetic disorder that your baby gets when they have an extra 13th chromosome. In other words, they have three copies of their chromosome 13 when they should have just two. It happens when cells divide abnormally during reproduction, and create extra genetic material on chromosome 13.
The additional chromosome can come from either the egg or the sperm, but doctors think that the chances a woman will have a baby with any chromosome abnormality go up after age 35.
The extra 13th chromosome causes severe mental and physical problems. Unfortunately, most babies born with it don’t live past their first month or year. But some can survive for years.
How Is It Diagnosed?
Your doctor might spot physical signs of trisomy 13 during your routine first-trimester fetal ultrasounds. Or it could show up in tests such as cell-free DNA screening (NIPT) or the PAPP-A (pregnancy-associated plasma protein A).
These are all screening tests, which means they can’t tell your doctor whether your baby definitely has trisomy 13. They only alert your doctor that your baby is more likely to have trisomy 13, and that you need more tests to confirm it.
Birth Defects
Babies born with trisomy 13 often have a low birthweight. They usually have brain-structure problems, which can affect their facial development, as well. A baby with trisomy 13 may have eyes set close together and an underdeveloped nose or nostrils and cleft lip or palate.
Other birth defects of trisomy 13 include:
Clenched hands
Cleft lip or palate
Extra fingers or toes (polydactyly)
Hernias
Kidney, wrist, or scalp problems
Low-set ears
Small head (microcephaly)
Undescended testes
Babies born with trisomy 13 can have many health problems, and more than 80% don’t survive more than a few weeks. Those that do can have serious complications including:
Breathing difficulties
Congenital heart defects
Hearing loss
High blood pressure (hypertension)
Intellectual disabilities
Neurological problems
Pneumonia
Seizures
Slow growth
Trouble feeding or digesting food
What Are the Treatments?
There is no cure for trisomy 13, and treatments focus on your baby’s symptoms. These can include surgery and therapy. Although, depending on the severity of your baby’s issues, some doctors may choose to wait and consider any measures based on the chances of your baby’s survival.
Trisomy 13 isn’t always fatal. But doctors can’t predict how long a baby might live if they don’t have any immediate life-threatening problems. However, babies born with trisomy 13 rarely live into their teens.
