- This topic has 1 reply, 2 voices, and was last updated 3 weeks, 5 days ago by
.
-
Posts
-
-
-
First, take a breath. A high-risk screening result does not mean your babies definitely have a condition. It means further testing is recommended to find out.
Two of the most common misunderstandings Team Genetidoc sees in prenatal screening are treating a screening result as a diagnosis, and assuming a high-risk result is a confirmed problem. Both can cause unnecessary distress and rushed decisions.
Step one: genetic counseling
A genetic counselor and clinical geneticist will review your result alongside your scans, your twin type and your history. They will explain what the result means for each baby, whether anything such as a vanishing twin could explain it, and what your options are. Bring all your scan reports and blood test reports to this session.
Step two: diagnostic testing, if you choose it
Diagnostic tests examine cells from the pregnancy directly and can confirm or rule out a chromosome condition.
Chorionic villus sampling takes a small sample of placental tissue, usually between 11 and 14 weeks.
Amniocentesis takes a small sample of the fluid around the baby, usually from 15 or 16 weeks.The cells are then studied with one of two tests. Karyotyping gives a picture of all the chromosomes. Chromosomal microarray analysis is a more detailed test that can find smaller missing or extra pieces of chromosomes.
How this works with twins
Twins with two placentas: each baby is usually sampled separately. The specialist carefully maps which sample came from which baby, so that results can be matched to the right twin.
Twins sharing one placenta: one sample is often enough when the babies look alike on scan, because they are almost always genetically identical. If one baby shows a problem on scan and the other does not, both may be sampled.The risk of pregnancy loss after these procedures is slightly higher in twins than in single pregnancies. They should be done by a fetal medicine specialist experienced with twins.
Genetidoc does not perform these procedures itself. The team works alongside your obstetrician or fetal medicine specialist to choose the right laboratory test and interpret the results with you.
An illustrative example (composite, details changed)
A couple expecting twins who shared one placenta received a high-risk Non-Invasive Prenatal Testing result for Down syndrome. They assumed only one baby might be affected.
In counseling, they learned that twins sharing a placenta are almost always identical, so the result most likely applied to both. Amniocentesis confirmed the result, and the genetic team explained what it meant for each baby and the support available.
If only one twin is affected
In non-identical twins, one baby can have a chromosome condition while the other is healthy. This is one of the hardest situations a family can face.
Options may include continuing the pregnancy with additional planning and support, or, in some situations, a procedure called selective reduction. Whether this is possible, and how safe it is for the healthy twin, depends on whether the twins share a placenta and on the stage of pregnancy. These procedures are done only at specialized fetal medicine centres, and Indian law sets time limits and conditions that your fetal medicine team will explain.
-
- You must be logged in to reply to this topic.