How to detect chromosomal abnormalities in babies in the womb & bull; hello healthy

The mother must really take care of her pregnancy so that the baby will be born healthy. However, sometimes some babies can be born with chromosomal abnormalities with no known cause. Actually, there are ways to find out if the baby in the womb has chromosomal abnormalities or not, which is done before the baby is born.

What are chromosomal abnormalities?

Before discussing how to detect it, what must be done to find out if a baby has chromosomes or not, we should first know what a chromosomal abnormality is.

Chromosomal abnormalities occur when there is a defect in the chromosomes or in the genetic makeup of the chromosomes of the unborn baby. This chromosomal abnormality can be in the form of additional material that may be attached to a chromosome or the presence of part or all of the chromosome is missing, or chromosome defects.

Any addition or decrease in chromosomal material can interfere with normal development and function in the baby's body. So there are many different types that are caused due to this chromosomal abnormality. For example, Down syndrome has three chromosomes number 21 or Edward syndrome has an additional chromosome number 18, and many more.

How to detect chromosomal abnormalities?

Several tests can be done to detect chromosomal abnormalities during pregnancy, including:

Amniocentesis

Amniocentesis is a test performed to diagnose chromosomal abnormalities and neural tube defects (neural tube defects), such as spina bifida. Amniocentesis is done by taking a sample of the amniotic fluid that surrounds the fetus.

Amniocentesis is usually performed by pregnant women who are at high risk for chromosomal abnormalities at 15-20 weeks of gestation (second trimester), but can be done at any time during pregnancy. Pregnant women who have a high risk of having chromosomal abnormalities, including those who will give birth over the age of 35 years or who have had a screening test for maternal serum abnormalities.

Amniocentesis is performed by inserting a needle through the mother's stomach into the baby's amniotic sac in the uterus to obtain a sample of the baby's amniotic fluid. Help ultrasound needed to guide the insertion and removal of needles. About three tablespoons of amniotic fluid are then removed through the needle. The cells from this amniotic fluid are then used for genetic testing in the laboratory. The results will usually come out in about 10 days to 2 weeks, depending on each laboratory. The risk of miscarriage after amniocentesis is 1/500 to 1/1000 of pregnancies.

Women who are pregnant with twins need to have a sample of each baby's amniotic fluid to study each baby. This depends on the position of the baby and the placenta, the amount of fluid, and the woman's anatomy, because sometimes amniocentesis is not possible. Keep in mind that the amniotic fluid contains baby cells that contain genetic information.

Chorionic Villus Sampling (CVS)

If amniocentesis involves taking a sample of amniotic fluid, CVS involves taking a sample of the placental tissue. The tissue in the placenta has the same genetic material as that of the fetus, so this tissue can be tested for chromosomal abnormalities and some other genetic problems. However, CVS cannot test for open neural tube defects. Therefore, pregnant women who have had a CVS test may also need a blood test in the second trimester to determine the risk of neural tube defects because CVS cannot provide these test results.

CVS is usually performed on pregnant women who are at risk for chromosomal abnormalities or who have a history of genetic defects. CVS can be done between 10-13 weeks of gestation (first trimester). However, CVS can lead to about 1/250 to 1/300 risk of miscarriage.

CVS is done by inserting a small tube (catheter) through the vagina or cervix (choose one) into the placenta. The entry and discharge of this small tube is also guided by ultrasound. A small piece of placental tissue is then removed and sent to a laboratory for genetic testing. Results from CVS usually come out in about 10 days to 2 weeks, depending on each laboratory.

Women pregnant with twins usually require a sample from each placenta, but this is not always possible due to the difficulty of the procedure and placement of the placenta. Some pregnant women are prohibited from doing this procedure, such as in pregnant women with active vaginal infections (for example, herpes or gonorrhea). Pregnant women who do not get accurate results after undergoing this procedure may need a follow-up amniocentesis. Incomplete or inconclusive results may occur because the doctor may take a sample that does not have enough tissue to grow in the laboratory.