Screening of mothers to detect Down syndrome: a practical approach in a resource limited setting

Shaji Thomas John, Kizhanipurath Gayathri


Background: Advanced maternal age, history of abortion and/or bleeding in pregnancy are risk factors for the birth of a chromosomally abnormal child. This study was done to find out their relationship especially in Down syndrome (DS).

Methods: Retrospective observational study was done in children with DS and their mothers, from a major referral institution in India over a period of 20 years. The prevalence of abortion/bleeding in pregnancy with the age of mothers were analysed using statistical package for social sciences (SPSS) V20 software and compared in all the cytogenetic profiles.

Results: In mothers less than 35 years 21.8% had abortion, 8% had bleeding and 4.5% had both abortion and bleeding. In mothers more than 35 years 25% had abortion, 7.3% had bleeding and 4% had both abortion and bleeding. Thus 34.5% had abortion/bleeding in mothers less than 35 years and 36.8% in those above 35 years. 15.25% mothers were more than 35 years. When the individual cytogenetic pattern and the prevalence of abortion/bleeding were analysed in maternal age group less than 35 years; a higher prevalence was seen in the non-disjunction group (34.2%), followed by translocation (24%) and mosaic (21.42%). In maternal age group >35 years prevalence was high, though not statistically significant, in the mosaic group (66.67%) followed by non-disjunction (43%).

Conclusions: Mothers with a history of abortion/bleeding and those above 35 years constituted 44.7%. Ideally all pregnant women should be screened for chromosomal aneuploidies, but in resource limited countries screening should be done at least in the above noted high risk groups.


Abortion, Bleeding, Maternal age, Down syndrome

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