Difficulties in selecting an appropriate neonatal thyroid stimulating hormone (TSH) screening threshold.

Background: The UK Newborn Screening Programme Centre recommends that a blood spot thyroid stimulating hormone (TSH) cut-off of 10 mU/l is used to detect congenital hypothyroidism (CHT). As the value used varies from 5 to 10 mU/l, we examined the implications of altering this threshold.

Methods: Our regional blood spot TSH cut-off is 6 mU/l.

Second trimester maternal serum ADAM12 levels in Down's syndrome pregnancies.

Objective: To estimate the utility of maternal serum ADAM12 as a Down's syndrome marker.

Methods: Samples from 71 Down's syndrome affected pregnancies were retrieved from - 20 degrees C storage together with 710 controls matched for gestation and storage time. ADAM12 was measured prior to identification of the affected pregnancies, and expressed in multiples of the gestation-specific median (MoM).