Decades of Progress: A Seventeen-Year Journey of Prenatal Diagnostic Excellence

Abstract

Objective: To analyze experience of CVS in a single center for different disorders.
Methodology:  This retrospective study analyzed 4116 CVS procedures performed at NIBD & BMT (2004–2022) for prenatal diagnosis of ?-thalassemia, Down’s syndrome, and other genetic disorders. Chorionic villi samples were collected under ultrasound guidance, followed by DNA extraction (QIAamp kit) and ARMS-PCR to detect 15 ?-thalassemia mutations. Maternal contamination was ruled out via STR analysis (D13S317, D18S51, D21S11). Karyotyping was performed for chromosomal anomalies. Data included demographics, consanguinity, diagnostic outcomes, and parental decisions on pregnancy termination. Statistical analysis calculated proportions and cumulative prevalence.

Results: A total of 4116 CVS were performed since 2014 till to date with age from 17 to 49 years, Majority 2938 (71.4%) subjects were within age group 25-35 years. Out of 3629 CVS performed for thalassemia, 863(21.5%) were thalassemia major, 1883(45.4%) were carrier and 859 (20.4%) were normal, while 24(0.6%) fetuses revealed unidentified mutations and were advised to undergo advanced testing. Karyotyping for Trisomies of 79 fetuses revealed normal karyotype in 77 while 2 fetuses positive for Trisomy 21. Out of 4116 CVS performed 59% and 14.1% were belong to sindh and KPK respectively. Whereas equal and minor percent of patients came from province of Baluchistan and Punjab.  Overall, 866 (21%) fetuses were affected by the disease and 863 (20.9%) parents opted for termination of pregnancy. STR was informative in all the cases except 4/2522(0.15%).

Conclusion: Chorionic Villus Sampling is an effective method for prevention of inherited diseases that is opted comfortably by all patients.