Amniocentesis rate and the detection of down syndrome and other chromosomal anomalies in Israel

Abstract

We investigated the contribution of different screening criteria to the prenatal detection of Down syndrome (DS) as well as other chromosomal anomalies in the Jewish population in Israel during 1990 and 1992. There was a significant decrease (P < 0.03) in the incidence of DS live-births during 1992 (40:78 442) compared with 1990 (69:73 751) which paralleled a marked increase in total prenatal testing and in DS cases detected prenatally. Private laboratories, which perform amniocenteses mostly for women with a low risk of DS and without genetic counselling, had a significantly lower detection rate (1:917) compared with that of the genetic institutes, which following genetic counselling test both women > or = 37 years of age (1:91) and women younger than 37 years (1:113). The detection of chromosomal anomalies other than DS was less affected by the reason for amniocentesis. Amniocentesis indicated by maternal serum marker screening of women younger than 37 years identified a greater number of chromosomal anomalies other than DS than amniocentesis based on age (> or = 37 years) alone (111:9604 versus 94:9810; P < 0.06). Prenatal detection of DS is most effective when the indication for amniocentesis follows genetic counselling. The increasing use of maternal serum marker screening leads to a significant improvement in the positive detection rate of chromosomal anomalies other than DS in young women.

Mid‐gestation Down syndrome screening test and pregnancy outcome among unstimulated assisted‐conception pregnancies

“…The reference MoM values were calculated from our own local population as established in Zer Medical Laboratories during the same period of time. The results of the screening tests are presented in Israel as risk for a DS live birth, and the cutoff level for recommending fetal karyotyping is ≥1 : 380 (Shohat et al, 1995).…”

Prenatal diagnosis of Down syndrome: Ten year experience in the Israeli population

“…The DS prevention program in Israel is unique in its data completeness as described in previous studies [Davidov et al, 1994; Shohat et al, 1995a,b]. All the invasive prenatal tests (amniocentesis and chorionic villus sampling [CVS]) are reported as well as all of the cases of DS diagnosed at birth or detected by the prenatal tests.…”

“…While data were collected on both the Jewish and non‐Jewish populations, we concentrate here on the Jewish population. This is a population with a high percentage of pregnancies in women above the age of 35 years, with a high use of tests, and a large enough population to allow for sound statistical analysis [Davidov et al, 1994; Shohat et al, 1995a,b]. The non‐Jewish population in Israel comprises a relatively small group within the total number of pregnancies, with a relatively very low use of these tests.…”

Correlation and Overlapping between Nuchal Translucency and Triple Test among Down Syndrome-Affected Pregnancies

“…that the series does not fairly represent a DS population. Those figures, however, do represent the DS group in the Israeli population, since more than half of all DS-affected pregnancies were among the older age group, constituting 17% of the total number of deliveries [26]. Moreover, maternal age per se does not affect log MOM distribution of NT or serum markers among normal or DS-affected pregnancies.…”