Amniocontesis in early pregnancy (about 14-16 weeks) has now made it possible for prenatal diagnosis of conditions associated with chromosomal anomalies (e.g. Down's syndrom); many inborn errors of metabolism (e.g. Tay-sach disease, galactosemia, Maple syrup urine disease, Alpha thalassemia and neural tube defects). The indications for prenatal diagnosis are listed in following table:
Indications for prenatal diagnosis[51]
S. No.Indications
a.
Advanced Maternal age, previous child with chromosome aberration, intrauterine
Cytogenetics (amniocentesis, chorionic villus sampling)
b.
Biochemical disorders
Protein essay, DNA diagnosis
c.
Congenital anomaly
Sonography, Foetoscopy
d.
Screening for neural tube defects and trisomy
Maternal serium alpha-fetoprotein, and chorionic gonadotropin
Prenatal Diagnosis