In 1887 Landon-Down described a syndrome of mental handicap associated with various physical abnormalities and a supposed resemblance to members of the Mongol race. This unfortunately led to this condition becoming known as mongolism but the condition is now known as Down's syndrome or trisomy 21.
Down's syndrome is the commonest of the chromosomal disorders and a major cause of mental retardation. The incidence is approximately 1 in 700 births (1).
The incidence of Down's syndrome, as with other trisomic abnormalities, increases with maternal age. In the last decade the number of live births to women aged 40+ has doubled, with a 6% increase in fertility seen in 2006 (2). Note however that mothers of any age can have infants with Down's syndrome and the majority of Down's syndrome babies are born to younger mothers.
- advice from the UK National Screening Committee on antenatal screening for Down's syndrome..click here
- 1. Down's Syndrome Report 2007 Accessed at www.wolfson.qmul.ac-uk/ndscr
- 2. : http://www.statistics.gove.uk/cci/nugget.asp?id+369