noninvasive prenatal testing: indications and results – … prenatal testing (nipt) ü positioning...
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6th Congress of the SEESPMZagreb, 5th December 2015
Noninvasive prenatal testing: indications and results –initial experience from Serbia
Noninvasive prenatal testing (NIPT)
ü Cell-free fetal DNA (cffDNA) in the maternal blood• Detectable after the 5w of gestation, dissapears few hours
after delivery
• 3-13% of total maternal cfDNA after 10w
• Amount of cffDNA essential for the accurate test results
üMassively parallel shotgun sequencing (MPSS), chromosome-specific sequencing (CSS), single-nucleotide-polymorphism-based analysis (SNP)
ü Clinically available since 2011
Noninvasive prenatal testing (NIPT)ü Positioning NIPT in the field of prenatal genetic screening and
diagnosisü Advantagesü Lower number of invasive prenatal diagnostic proceduresü Obtaining results early in pregnancyü High accuracy of the test
ü Possible problems ü Information lost (cFTS: NT, preeclampsia, IUGR screening; AFP)ü “Routinization” of the screening procedures and lack of
competent counselingü Sex-selection for non-medical issuesü Cost-effectiveness
NIPT in Serbia
ü Available from July 2013
ü 5 companies
ü Price range 590-790e (depending on the company and No of aneuplodies tested)
ü Expences not covered by insurance
üNo prevoius medical referral necessary (“direct to consumer basis”)
Patients and methods
ü Women with singleton pregnancies undergoing NIPT in a single private center for laboratory diagnostics in Belgrade
ü Written consent for the “provision of the personal data and follow-up information on the outcome of the pregnancy”
ü Questionnaire containing information on the gestational age and indication for the testing filled in by each patient on the day of blood taking
ü Patients contacted via e-mail and pregnancy outcomes recorded
NIPT – initial experience from Serbia
ü Study period July 2013-July 2015
ü Available follow-up data gathered until November 2015
ü 283 patientsü Average GA 15w (range 10w
– 32w)ü Average age 35.2 yrs (range
20 – 45 yrs)
24
62
83
114
0
20
40
60
80
100
120
2013 2014 / I 2014 / II 2015
NIPT – initial experience from Serbia
ü Insufficient cffDNA concentration in 7 (2.5%) patients
ü Follow-up data on pregnancy outcome available for 260 (91.9%) patients
ü 52 ongoing pregnancies
ü 3 positive NIPT results
ü 2 Trisomy 21 in Pts aged 37 and 40 yrs in 14w and 15w GA, respectively
üboth subsequently confirmed by AC; both underwent induced abortion
ü 1 Trisomy 18 in Pt aged 34 yrs, no follow-up data available
NIPT – reasons for taking the test
21%
59%
13%4% 3% "higher accuracy than
cFTS"Age > 35 yrs
High risk on cFTS
IVF/infertility
Family history/previouspregnancy
NIPT – reasons for taking the test
(31.4%) patients < 35 yrs
N (%)
Family history / prevoius pregnancy 8 (9.0%)
IVF / infertility 10 (11.2%)
High risk on cFTS 11 (12.4%)
Higher accuracy than cFTS 60 (67.4%)
89
NIPT – reasons for taking the test
ü 194 (68.6%) patients > 35 yrs
N (%)
Instead / before age-indicated AC 168 (86.6%)
IVF / infertility 1 (0.5%) *
High risk on cFTS 25 (12.9%)
194
* 69 (42.4%) patients in the first indication group conceived after IVF / infertility
NIPT – results
N %
Induced abortion 2 0.7%
Missed abortion 2 0.7%
Ongoing pregnancy 52 18.4%
Lost to follow-up 23 8.1%
Livebirth (uneventful) 204 72.1%
ü Limitations of the study
üRetrospective
üLimited No of patients
üPredesigned questionnaire, limited data
üUnavailable for follow-up
ü Screening the situation with the screening test
Conclusions
üNIPT popularity among patients growing
ü Expected test performance
ü Indications
ü59% age > 35 yrs
ü“Higher accuracy than cFTS” 21% of the patients ―The proportion of patients who underwent cFTS
―Replacement for the invasive prenatal genetic diagnosis
Conclusions
üMedical referral?
ü Informing the patients?
üDid the patients understand well both the advantages and limitations of the test?
üWhat is the health-care providers’ knowledge and attitude towards the NIPT?
THANK YOU!