Wide scope prenatal diagnosis at Kuopio University Hospital 1997-1998: integration of gene tests and fetal karyotyping.

OBJECTIVE

To investigate the applicability of carrier screening in women undergoing invasive prenatal diagnosis.

DESIGN

Prospective study.

SETTING

University-based clinic.

PARTICIPANTS

Two hundred and fifty-six pregnant women.

METHODS

Gene tests were offered for fragile X syndrome, aspartylglycosaminuria and infantile neuronal ceroid lipofuscinosis at the time of invasive prenatal testing.

RESULTS

The overall uptake of the tests was 92%. Previously unrecognised carriership was found in 10 women: aspartylglycosaminuria (7); infantile neuronal ceroid lipofuscinosis (2) and fragile X (1). Fetal genotyping was carried out in one carrier of aspartylglycosaminuria whose partner was also a carrier, and in one woman who was found to have fragile X premutation. Both fetuses were unaffected.

CONCLUSION

Carrier screening for single-gene disorders is feasible and well accepted among pregnant women undergoing invasive prenatal testing. The major benefit is that there is no need to consider extra invasive tests when carriership is detected. Incorporation of genetic testing into fetal karyotyping gives more security to future parents.