How accurate are 12 week dating scans
How accurate are 12 week dating scans - dating finder ru maria php
This is presuming that the pregnancy is actually at this stage of development.
It is usually done as part of your first pregnancy visit.You’ll have to wait three or four weeks to get the results back from the laboratory. This test, done between the 16th and 20th week of pregnancy, detects chromosomal disorders, the most common of which is Down Syndrome.Your obstetrician withdraws a small amount of the amniotic fluid surrounding the foetus by inserting a thin, hollow needle through your abdomen and into the uterus. This procedure only takes a few minutes and the fluid is then sent to the laboratory for tests.“Genetic screening is not the only issue, it also seeks out structural anomalies and common problems such as Diaphragmatic hernias and Congenital Heart Disease.Most dating scans are done with a trans-abdominal transducer and a fullish bladder.If the pregnancy is very early the gestation sac and fetus will not be big enough to see, so the transvaginal approach will give better pictures.
For transvaginal ultrasound you can have an empty bladder Dating scans are usually recommended if there is doubt about the validity of the last menstrual period.
The following tests should be performed if there is sufficient history that suggests a medical problem or if the patient is exhibiting signs of the lack of it: iron levels, oral glucose tolerance test, thyroid function tests, uric acid and liver function.
“A detailed Foetal Anomaly Scan should be performed at twenty to 22 weeks gestation,” says Dr Tan.
Ultrasound is used to guide the needle so as not to harm your baby.
The procedure takes only a few minutes and the tissue is then sent to the laboratory for tests.
The sensitivity of the test is approximately 90 per cent.