However sometimes, when a genetic disorder occurs in a pregnancy, it is due to a random genetic accident. Even babies of absolutely fit and fine parents who have no medical history of any genetic abnormality can sometime be affected at birth.
Genetic testing is to be carried on both the parents. It should be ideally done before the pregnancy is planned so that the parents know exactly what the chances of their baby being affected are. If there are high chances that the baby can be born with the abnormal gene traits, then other options like egg donation or sperm donation can even be thought about.
But in case, the pregnancy is not planned or genetic testing has been skipped before conceiving, then the tests should be done as early as possible. With a diagnosis of the parents and a look into the family history, doctors can single out diseases from which the child is more prone to suffer.
For example, if the baby is at an increased risk for having cystic fibrosis or sickle cell disease, the doctor can look for those conditions specifically either through a chorionic villi sampling or amniocentesis.
Most genetic disorders are known as “recessive disorders,” which means that each parent needs to pass along an affected gene to the baby in order for the child to be affected. A genetic testing will clearly tell you the following things:
- If neither of the parents is a carrier, the baby will not inherit the condition.
- If one of the parents is a carrier, but the partner is not, the baby will not inherit the condition.
- If both the parents are carriers, the child will have a 25 percent chance of inheriting the condition.
Some common genetic disorders are:
- Cystic fibrosis – a life-threatening condition that causes lung damage and digestive problems.
- Sickle cell disease – a blood disorder that leads to anaemia, a weakened immune system, and other health complications.
- Thalassaemia – another blood disorder that causes anaemia and bone growth and liver problems; in severe cases, babies born with the condition may not survive.
- Tay – Sachs disease – a disorder of the central nervous system that is usually fatal in early childhood.
- Fragile X Syndrome – a condition that can cause developmental problems, including learning disabilities and mental retardation.
Some common tests available for detecting different genital and birth defects are:
- Ultrasound: A safe test that uses high-frequency sound waves to produce an image of your baby.
- First-trimester screening: Generally done between the 11th and 14th The results look for problems with the baby’s chromosomes, such as Down syndrome.
- Quad Marker screening: Blood test performed between the 15th and 20th weeks of pregnancy. Used to detect problems with a baby’s brain and spinal cord.
- Amniocentesis: This can be used to test for Sickle cell disease, Cystic fibrosis, Muscular dystrophy, Tay-Sachs disease, Neural tube defects.
- Chorionic Villus sampling: It is an alternative to amniocentesis, and it can be performed earlier in the pregnancy.
- Non-invasive prenatal diagnosis: Also called cell-free DNA testing, it is done between 10 and 22 weeks of pregnancy.