Clinical follow-up of high mid-trimester maternal serum intact human chorionic gonadotrophin concentrations in singleton pregnancies

Mid-trimester biochemical screening of 38 143 pregnancies in south-east Sco tland revealed 127 cases (0.34 per cent) in which the maternal serum (MS) i ntact human chorionic gonadotrophin (hCG) concentration was greater than or equal to 4 multiples of the median in singleton pregnancies (MOM). Three w ere lost to follow-up but in 72 (58 per cent) complications developed or th ere were associated fetal abnormalities. This percentage was greatest at ve ry high hCG concentrations, 92 per cent with hCG greater than or equal to 1 0 MOM (n = 12) compared with 48 per cent with hCG concentrations of 4-4.99 MOM (n = 69). 22 cases had an MS alpha-fetoprotein greater than or equal to 2 MOM in addition to an MS hCG greater than or equal to 4 MOM, and in only 3 of these was the pregnancy uneventful; 86 per cent were associated with abnormalities or pregnancy complications. Copyright (C) 1999 John Wiley & S ons, Ltd.