(CVS) Sampling
Sampling of the placenta is for prenatal diagnosis. The sample will be taken from the placenta. The genetic information of placenta is similar to that of the fetus the investigation of which facilitates genetic disorder diagnosis.
Placenta
Placenta is the tissue apart from the fetus which is connected to the fetus by the umbilical cord. The placenta connects to the wall of the uterus and is responsible for feeding the fetus through connection with the mothers blood system. Contrary to the impression of some people, sampling will not be performed from the fetus, but it is taken directly from the placenta under the guidance of an ultrasound device.
Appropriate Gestational Age for Sampling of the Placenta
The most appropriate gestational age for the sampling of the placenta is 10 to 12 weeks of pregnancy. Sampling in gestational age less than 10 weeks is not recommended because it increases the risk of miscarriage.
The Method of Sampling of the Placenta
Sampling of the placenta in this clinic will be performed through the abdomen skin. First, fetal heart rate will be evaluated by ultrasound. Then, the position and thickness of the placenta will be determined and the sampling needle will be inserted into the placenta and sampling will be performed under ultrasound guidance.
Sampling is performed without anesthesia and only with local analgesia. Local analgesia has a pain like intramuscular injection which can be easily tolerated.
Sampling Will Not Damage the Fetus
Sampling of placenta will be performed by an experienced specialist. Given that the needle will be inserted only into the placenta, it will never lead to direct harm to the fetus.
After sampling of the placenta, there is a possibility of miscarriage, the rate of which in various centers around the world is 2-4%. In a review of the patients in this clinic, miscarriage rate was reported less than 2%, which is significantly less the centers abroad.
Post-Sampling Problems
Following the sampling, spotting of bleeding or discharge may occur, which will be usually improved spontaneously and need no particular medicine.
In individuals with no history of miscarriage of bleeding, they need 24 hours of rest at home after sampling. However, people with a history of miscarriage or bleeding need more rest.
The Number of Sampling Sessions
In most cases, a sufficient amount of sample will be prepared from the placenta in one session. However, in some case, due to the small amount of placenta sample, the existence of maternal tissue in the sample, or the suspiciousness of the test result, sampling need to be repeated.
Required Preparations
– Removal of unwanted hair from uterus area
– Having the laboratorys introduction letter
– Having a companion to do the paperwork
– Fasting and stopping medicines
It is better to eat little breakfast in the morning of the day of sampling. If the patient takes a particular medicine prescribed by the doctor, he/she could take the medicine as usual on the day of sampling and there is no need to stop taking it.