First-trimester maternal serum human chorionic gonadotrophin as a marker for fetal chromosomal disorders. The Dutch Working Party on Prenatal Diagnosis.
The Dutch Working Party on Prenatal Diagnosis has initiated a study on the possibilities of first-trimester screening for fetal chromosomal disorders. We report on maternal serum human chorionic gonadotrophin (MS-hCG) measurements in 1348 pregnancies with a chromosomally normal fetus and 53 pregnancies with a chromosomally abnormal fetus. The median MS-hCG concentration in 24 pregnancies with Down's syndrome was 1.19 multiples of the normal median (MoM). The MS-hCG distributions in normal and Down's syndrome pregnancies did not differ significantly (t-test: t = 1.945, p greater than 0.05). We also found no difference between normal pregnancies and pregnancies with other chromosomal disorders (six cases of trisomy 18, MoM = 0.80; four cases of sex chromosome abnormality, MoM = 1.01; 17 cases of chromosomal mosaicism in chorionic villi, MoM = 1.11). Selecting an upper limit at the 90th centile could detect 25 per cent of pregnancies with Down's syndrome. We conclude that, in the first trimester, MS-hCG as a screening factor for Down's syndrome is of minor value. However, MS-hCG could be a useful factor in a first-trimester screening programme based on a combination of markers.
Van Lith
J M
JM
Department of Obstetrics and Gynaecology, University Hospital Groningen, The Netherlands.
D006063:Chorionic Gonadotropin / Q000097:blood*; D015193:Chorionic Villi Sampling; D002869:Chromosome Aberrations / Q000175:diagnosis*; D025063:Chromosome Disorders; D004314:Down Syndrome / Q000175:diagnosis*; D005189:False Positive Reactions; D005260:Female; D006801:Humans; D007621:Karyotyping; D008403:Mass Screening / Q000379:methods; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D011296:Prenatal Diagnosis; D014314:Trisomy
D006063:Chorionic Gonadotropin