[Screening for Down's syndrome in the 10th to 13th week of pregnancy].

Objective: The implementation of antenatal screening for Down's syndrome at 10-13. week using nuchal translucency, maternal serum free subunit of human chorionic gonadotrophin and the mother's age.

Design: Nuchal translucency scan (NT) and serum free beta human chorionic gonadotrophin subunit (FB hCG) were measured at 283 consecutive pregnant women booked at the same antenatal care facility between 10-13. gestational week.

Setting: Antenatal screening center Klimentska, Prague.

Methods: Medians of both markers according to gestational age as well as retrospective combined risk of Down's syndrome were assessed.

Results: 95 per cent of NT measurements was below 1.77 multiples of median. 95 per cent of FB hCG measurements was below 1.88 multiples of median. Combined risk higher than 1/300 had 1 per cent mothers (total 3 screen positive results).

Conclusion: The results of this pilot study serve for implementation of screening for Down's syndrome at 10-13. week as well as for integration of both first and second trimester screening systems.