What Is First Trimester Screening?

First trimester screening estimates the probability of certain fetal chromosomal conditions, including:

• Down syndrome, or trisomy 21
• Edwards syndrome, or trisomy 18
• Patau syndrome, or trisomy 13 in some screening programs

It is a screening test, not a definitive diagnosis. A higher-risk result does not confirm that the fetus has a chromosomal condition.

What Does the Screening Include?

Depending on the clinic and selected program, screening may involve:

• Review of maternal age and medical history
• Ultrasound measurement of nuchal translucency
• Assessment of early fetal anatomy
• Maternal blood testing
• Confirmation of gestational age
• Discussion of noninvasive prenatal testing
• Genetic counseling when appropriate

Screening options and calculation methods may differ among Busan medical providers.

When Is First Trimester Screening Performed?

The ultrasound and blood tests must be completed within specific gestational periods. Patients should contact an OB-GYN early in pregnancy rather than waiting until the end of the first trimester.

Accurate timing is based on ultrasound measurements and the healthcare provider’s screening protocol.

Nuchal Translucency Ultrasound

Nuchal translucency screening measures fluid beneath the skin at the back of the fetus’s neck. The measurement is combined with other factors to estimate chromosomal risk.

An increased measurement can be associated with chromosomal or structural conditions, but it does not provide a diagnosis. Further testing may be recommended.

First Trimester Screening vs. NIPT

Noninvasive prenatal testing, or NIPT, analyzes placental DNA fragments in maternal blood. It generally provides more accurate screening for common trisomies than traditional combined screening, but it remains a screening test.

Your OB-GYN may discuss:

• Traditional combined first trimester screening
• NIPT
• Ultrasound alone
• Diagnostic testing based on individual risk

The appropriate option depends on pregnancy stage, maternal age, medical history, ultrasound findings, cost, and personal preference.

What Happens After the Results?

AA lower-risk result reduces—but does not eliminate—the chance of a screened condition.

If results indicate a higher probability, the next steps may include:

• Detailed ultrasound
• NIPT when not already completed
• Genetic counseling
• Chorionic villus sampling
• Amniocentesis later in pregnancy
• Consultation with a maternal-fetal medicine specialist

Diagnostic procedures provide more definitive information but involve different benefits and risks.

First Trimester Screening for Foreigners in Busan

International patients can arrange screening through private OB-GYN clinics, maternity hospitals, or university hospitals around Seomyeon, Haeundae, Centum City, Gwangalli, Nam-gu, and other Busan areas.

Before booking, ask about:

• Screening types available
• Appropriate appointment timing
• English-speaking consultations
• Testing fees and insurance coverage
• English laboratory reports
• Genetic counseling
• High-risk pregnancy referrals

Patients transferring care should bring previous ultrasound images, pregnancy records, and laboratory results.

Preparing for Your Appointment

Bring:

• Estimated due date
• Date of your last menstrual period
• Previous ultrasound reports
• Fertility-treatment information
• Medication and supplement list
• Personal and family medical history
• Previous prenatal screening results

Your clinic will explain whether fasting or a full bladder is required.

Frequently Asked Questions

Does first trimester screening diagnose Down syndrome?
No. It estimates probability. Diagnostic testing is required to confirm a chromosomal condition.

Is NIPT the same as first trimester screening?
No. NIPT is a blood-based screening method. It may be offered instead of or alongside ultrasound-based screening.

Is an ultrasound still needed after NIPT?
Yes. NIPT does not evaluate all structural abnormalities or replace medically recommended ultrasound examinations.

What does a higher-risk result mean?
It means the calculated probability is above the program’s cutoff. It does not mean the fetus definitely has the condition.

Can twins have first trimester screening?
Yes, but test accuracy and interpretation can differ. Specialized counseling may be recommended.

Book First Trimester Screening in Busan

Contact a Busan OB-GYN provider early in pregnancy to discuss screening options, accurate timing, ultrasound, NIPT, and any recommended follow-up testing.