Prenatal screenings

The aim of prenatal screenings is to improve the treatment of the baby and reduce morbidity and mortality in the newborn. Participation in prenatal screenings is voluntary. You can get information about prenatal screenings and related further examinations from your maternity clinic.

If you wish to test for chromosomal abnormalities (trisomies 21, 18 and 13) with a combined first-trimester screening, the child health clinic can write you a referral to a blood sample that is needed for the test. (See the dates of prenatal testing)

Usually, the client books the appointment for a general ultrasound examination for the combined first-trimester screening themselves digitally through OmaTays.
If you do not have online banking IDs or you need an interpreter for the appointment, the child health clinic will write a referral for the ultrasound examination.

If the client has received timely advice on combined screening and a referral to the laboratory, but has not given a sample yet, we carry out a general first-trimester ultrasound scan.

If you have turned 40 years of age by the recommended time of the combined screening (pregnancy week 9+0–13 +6), you will be offered a NIPT test and a general first-trimester ultrasound instead of the combined screening.
If the family does not wish to test for chromosomal abnormalities, book the appointment for a first-trimester ultrasound scan for week 10+0–13+6 of pregnancy.

Where are the tests taken?

Prenatal testing is carried out at Tays. The maternity ultrasound examination facilities (Äitiysultra) are located in Tays Central Hospital on the 3rd floor of Building D. You can register at the outpatient clinic using the registration machine in the main lobby or in the 3rd floor entrance lobby by the elevator.

The midwives at the ultrasound appointment explain what the examination results mean and which further examinations you still need.

It is possible to carry out further examinations at the maternity outpatient clinic if a suspicion of foetal abnormalities arise during screening.

Information on client fees

Dates and times of prenatal testing

Prenatal tests are carried out at the following times:

The first trimester general ultrasound scan

The scan is done between 10 weeks + 0 days to 13 weeks + 6 days of pregnancy.

The examination is performed across the abdominal wall or transvaginally. The examination aims to establish the due date of the pregnancy and the number of foetuses and ensures there are no severe structural abnormalities observed in early pregnancy.

Screening for chromosomal abnormalities

Screening for chromosomal abnormalities i.e. first-trimester combined screening, consists of:

A) First-trimester serum screening on the week 9+0–11+6 of pregnancy. The best time to take the laboratory tests is after 10 weeks of pregnancy.

• The blood sample is used to determine hormone and protein levels in the placenta and foetus.
• During the combined screening (on pregnancy week 9+0–13+6), a NIPT test and a general first-trimester ultrasound are offered (instead of a second-trimester serum screening) if the pregnant person is over 40 years of age or if the duration of their pregnancy differs from the normal duration as estimated during the general first-trimester ultrasound.

B) Nuchal translucency (NT) measured during the general first-trimester ultrasound examination on weeks 11+0–13+6 of pregnancy

• In addition to NT, the foetus's crown-rump length is also measured during the ultrasound examination. The mother's smoking, weight, and age impact potential risk factors. These questions are taken into account in the risk assessment.
• The best time for the ultrasound scan is on week 12 of pregnancy. 
• During the appointment, the risk for trisomies 21, 18 and 13 is calculated; if the risk is elevated, you will be advised on further examinations.

Combined screening detects more than 80% of chromosome abnormalities. The most common form of chromosome abnormality is Trisomy 21, i.e. Down syndrome.

If a severe structural anomality is suspected in an ultrasound screening (general first-trimester ultrasound examination and chromosome abnormality screening) or increased nuchal translucency is detected in the foetus, further examinations will be arranged.

Screening for structural anomalies

Screening for structural anomalies is done during weeks 18+0–21+6 of pregnancy.

The screening examines the structures of the foetus and detects possible abnormalities. Usually the examination is performed by a specialised midwife, but in high-risk pregnancies, the examination is performed by a specialist physician. The examination is best carried out in the maternity ultrasound unit around week 20 of pregnancy. This scan is conducted across the abdominal wall.

In addition to the structures of the foetus, the anomaly scan examines the growth of the foetus, the placement of the placenta, the amount of amniotic fluid and, if necessary, the length of the cervix is checked. This examination is usually performed by a doctor.

It is also possible to conduct the structural screening after 24+0 weeks of pregnancy. At that point, terminating the pregnancy is no longer possible under Finnish law, even if a severe structural abnormality is detected in the foetus.