The number of babies born with malformations has soared by as much as 50% in five years, research conducted for a medical charity has revealed.

Some 48,000 families are affected each year, with 3,000 birth defects being displayed. The total amounts to one in 16 births - or 124 babies each day - and is six times higher than the government's figures for neonatal abnormalities.

The research, by the Birth Defects Foundation (BDF), a charity set up by parents and doctors, shows a steep increase in three specific areas: cleft palate, gastroschisis and hypospadias. The steepest rise was in the numbers of cleft lips or palate, which had risen from 5.9 cases per 10,000 births in 1995 to 9.2 cases in 1999.

Gastroschisis, where intestines protrude at birth, had risen from 1.3 to 1.9 cases; while hypospadias, in which the opening of a boy's penis is on the underside of the shaft, had increased from 7.5 to 8.5 cases.

No clear explanation for the increase has emerged, but possible factors include an increase in oestrogen-like substances in the diet and the use of recreational drugs.

Michael Patton, the BDF's medical director and head of medical genetics at St George's hospital, Tooting, told the Independent: "Some substances in the diet, such as soya, contain phyto-oestragens which it has been suggested could have a feminising effect on males."

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