Research letter
Initial Data on a Non-invasive Prenatal Test (NIPT) for Trisomies 13, 18, and 21
A Retrospective Cohort Study Based on Billing Records of the BARMER Health Insurance Carrier
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Following the decision of the German Federal Joint Committee (G-BA) of September 19, 2019, and after finalizing the information provided to insured persons, the non-invasive prenatal test for trisomies 13, 18, and 21 (NIPT) became part of the list of services provided by the statutory health insurance funds as of July 01, 2022. Its introduction was closely bound with the aims of lowering the rate of invasive prenatal examinations and ensuring that the test would not be used for screening. So far, no valid data on utilization of the NIPT and achievement of these aims have been available (1). Reimbursement by health insurance funds now, for the first time, allows an evaluation of pertinent billing records.
Methods
A retrospective cohort study was conducted, drawing on the billing records of the BARMER health insurance carrier (comprising around 10% of the general population), which included age, sex, information on maternity allowance, and quarterly diagnoses (according to ICD-10-GM, the German modification of the International Statistical Classification of Diseases and Related Health Problems, 10th revision) and medical procedures performed on a daily outpatient (according to EBM-GOP, the doctors‘ fee schedule) and inpatient (according to OPS, the German procedure classification) basis.
The study population consisted of women receiving medical prenatal care between January 01, 2014, and March 31, 2024. Recourse to information on pregnancies prior to the introduction of the NIPT as a service covered by medical insurance allowed a comparison of the number of invasive prenatal tests. Pregnancies were identified using the endpoints birth (in an outpatient or inpatient setting) and miscarriage or abortion (as per maternity allowance), or the confirmed diagnosis ICD-10 O0 [2–5]). Medical prenatal care was considered to have been utilized if at least one billing for prenatal care (EBM-GOP 01770) had been registered. A detailed method description and further analyses and results are to be found at www.bifg.de/publikationen/epaper/10.30433/ePGSF.2024.008.
Results
A total of 766 245 pregnancies were identified for the observation period. Of these pregnancies, 30 365 NIPTs, 166 841 NIPT counselings, and 629 counselings for positive results were billed (Table).
The first quarter of 2024 revealed that 482 of 1000 pregnant women had undergone an NIPT. Three hundred and two () of 1000 pregnant women received counseling not followed by an NIPT, i.e., 38% (302/784) of the pregnant women opted against an NIPT after being counseled. Seven hundred eighty-four of 1000 pregnant women were counseled as part of the NIPT process. Of 1000 pregnant women who had opted for an NIPT after being counseled, eight had a positive (4/482) and 992 a negative NIPT result (478/482). Six and two of 1000 underwent amniocentesis and chorionic villus biopsy, respectively. Those pregnant women who took advantage of counseling received advice on average 3.3 times (billing code 01789 is valid for 5 minutes each time and may be billed four times per pregnancy). An average of 1.5 counselings were provided for a positive test result. Supplementary material is available for further analysis (2).
The Figure presents the age distribution of those pregnant women who took advantage of the NIPT. Utilization rates reached the 50% mark for 36 to 39-year-olds shortly after funding had been agreed and introduced, and rates were around 75% for women over 40. In 2024, about one in four pregnant women under 26 made use of an NIPT. Depending on their age, between 50 and 75% of all pregnant women had at least one counseling session for NIPT (not presented here).
Discussion
For the first time after its inclusion in the benefits catalog of the German statutory health insurance scheme, data on utilization of NIPT are now available. Those ensured with the BARMER health insurance carrier have a somewhat higher level of education which may have an impact on benefits; on the whole, however, we regard the results as representative. With an average utilization of almost 50% of pregnant women, the NIPT has ultimately become a screening test. Concerns about NIPT as a screening test had already been raised in the run-up to the agreement of funding (3). Furthermore, it was assumed that testing accuracy was by no means as good as assumed (4). The present article supports this assumption. From the number of counselings after positive tests, it follows that the actual number of false-positive results in real health care provision is four times higher than would have been expected for the stated specificity of 99.95%. This could be due to the increased utilization of the test by young women with a low risk of having a child with trisomy. Furthermore, an additional interrupted time series analysis (ITS) of the incidence of invasive prenatal tests has shown that the anticipated reduction of invasive prenatal tests did not occur, but instead there was an increase by 0.1 to 2.5 per 1000 pregnancies as compared with the expected value (2). Health insurance data have their limitations. For example, they contain no results or information about the quality of counseling. It is also not possible to reliably state the number of subsequent abortions. Monitoring of the NIPT, as is currently being discussed (5), would be desirable in order to learn more about the provision of health care services surrounding the use of NIPT. Such monitoring should include health insurance data and be supplemented by further information relating to, for example, abortions, clinical data and findings, and qualitative aspects such as the quality of counseling.
Conclusion
The present analysis shows that health insurance data provide a good picture of the utilization of the NIPT and of the trend of invasive procedures. However, the analysis also clearly indicates that the aims of the G-BA, i.e., to avoid the use of the NIPT as a screening test and to reduce the number of invasive prenatal diagnostic tests, have not been achieved. Monitoring of the NIPT would be desirable to expand the database on its utilization.
Dagmar Hertle, Danny Wende
BARMER Institute of Health Systems Research, Wuppertal, Germany (Hertle, Wende) dagmar.hertle@barmer.de
Conflict of interest statement
The authors declare that they have no conflict of interest.
Manuscript received on 09 October 2024, revised version accepted on 26 February 2025
Translated from the original German by Dr. Grahame Larkin
Cite this as:
Hertle D, Wende D: Initial data on a non-invasive prenatal test (NIPT) for trisomies 13, 18, and 21: A retrospective cohort study based on billing records of the BARMER health insurance carrier. Dtsch Arztebl Int 2025; 122: 283–4. DOI: 10.3238/arztebl.m2025.0043
