Comparison of false positive rates in prenatal combined screening and cell free DNA screening for trisomy 21

Status

Active, not recruiting

Phases

Unknown

Study type

Interventional

Source

ISRCTN

Registry ID

ISRCTN11174071

Enrollment

1400

Registered

2016-08-03

Start date

2016-08-01

Completion date

Unknown

Last updated

2022-10-24

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Prenatal screening for trisomy 21 Genetic Diseases Down syndrome, unspecified

Interventions

Following the normal ultrasound examination, randomization is performed into cell-free DNA screening or combined screening (maternal age, fetal NT, PAPP-A and free beta hCG). In the c

Eligibility

Sex/Gender

Female

Inclusion criteria

Inclusion criteria: 1. Patients coming for prenatal screening for trisomy at 11-13 weeks’ gestation 2. Singleton pregnancies 3. Normal ultrasound examination without increased nuchal translucency thickness >3.5mm and without fetal defects. If NT is increased or there are fetal defects, screening is not appropriate and invasive testing is performed 4. Informed consent

Exclusion criteria

Exclusion criteria: 1. Increased nuchal translucency thickness 2. Fetal defects 3. Multiple gestations

Design outcomes

Primary

Measure	Time frame
Number and proportion of false positive cases in each arm. False positive cases are defined as euploid cases with a risk for trisomy 21 > 1:100. The karyotype will either be obtained by invasive testing somedays after the screening test or after birth.	—

Secondary

Measure	Time frame
1. Number of cases that cannot be randomized (due to fetal defects, increased NT, multiple gestations). This data will become available at 11-13 weeks’ gestation. 2. Time interval between randomization and return of the blood results 3. Number of cases without results in each study arm. This data will be become available latest 2 weeks after the blood sample is taken. 4. Number of women who opt for invasive testing. This data will generally be available within the consecutive 4 weeks after the screening test but theoretically the invasive test can be carried out through the pregnancy. 5. Acceptance of each screening test. The patient will be contacted by us to assess the acceptance level of each of the screening tests. This will be done 4 weeks after the screening test and after birth.	—

Measure

Time frame

1. Number of cases that cannot be randomized (due to fetal defects, increased NT, multiple gestations). This data will become available at 11-13 weeks’ gestation. 2. Time interval between randomization and return of the blood results 3. Number of cases without results in each study arm. This data will be become available latest 2 weeks after the blood sample is taken. 4. Number of women who opt for invasive testing. This data will generally be available within the consecutive 4 weeks after the screening test but theoretically the invasive test can be carried out through the pregnancy. 5. Acceptance of each screening test. The patient will be contacted by us to assess the acceptance level of each of the screening tests. This will be done 4 weeks after the screening test and after birth.

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Countries

Germany

Outcome results

None listed

Source: ISRCTN (via WHO ICTRP) · Data processed: Feb 4, 2026