Grand Rounds

NIPS in Twin Pregnancy – The Latest Meta-Analysis

BACKGROUND AND PURPOSE:

Gil et al. (Ultrasound in Obstetrics & Gynecology, 2019) assessed the performance of NIPS for twin pregnancies

Prospective study and systematic review and meta-analysis
Prospective study
- Twin pregnancies between 10w0d and 14w1d
- Screened for trisomies 21, 18 and 13 using DANSR NIPS technology
NIPS performed after routine first-trimester combined testing
Systematic review and meta-analysis
- Peer-reviewed publications
- Clinical validation or implementation studies that assessed maternal cfDNA testing for trisomies 21, 18 and 13 in twin pregnancy
- Technology included massively parallel shotgun sequencing or targeted analysis (either by NGS or custom microarray)

Prospective study

997 twin pregnancies
NIPS correctly classified
- Trisomy 21: 94.1% (16/17 cases)
- Trisomy 18: 90.0% (9/10 cases)
- Trisomy 13: 50.0% (1/2 cases)
- True negatives (none of the 3 trisomies): 99.4% (962/968 cases)

Meta-Analysis

Above data combined with 7 studies from the literature
Trisomy 21 detection meta-analysis
- 56 trisomy 21 | 3718 non-trisomy 21 twin pregnancies
- Pooled weighted detection rate (DR): 98.2% (95% CI, 83.2–99.8%)
- FPR 0.05% (95% CI, 0.01–0.26%)
Trisomy 18 detection meta-analysis
- 18 trisomy 18 and 3143 non-trisomy 18 twin pregnancies
- The pooled weighted DR: 88.9% (95% CI, 64.8–97.2%)
- FPR 0.03% (95% CI, 0.00–0.33%)
Trisomy 13 detection meta-analysis
- There were only three affected cases
- Two (66.7%) were detected | FPR of 0.19% (5/2569)

NIPS in twins
- Trisomy 21 performance is similar to singleton pregnancy
- Trisomy 21 performance is superior to first-trimester combined test or second-trimester biochemical testing
The authors note that due to small ‘n’ for trisomies 13 and 18, accurate assessment is limited

< Previous

Next >