Old Mothers' Children Have Higher Diabetes (糖尿病) Risk Children of older mothers run a higher risk of developing insulin-dependent (胰岛素依赖型的) diabetes, the British Medical Journal said. 'A strong association was found between increasing maternal (母亲的) age at delivery and risk of (insulin-dependent) diabetes in the child. Risk was highest in firstborn children and decreased progressively with higher birth order,' Professor Edwin Gale and colleagues at Southmead Hospital in Bristol said. Diabetes is a serious, incurable, lifelong disease characterized (以……作为特性) by an inability to control the amount of sugar in the blood. Insulin-dependent diabetes, which mainly affects children, is treated by administering the hormone insulin. Gale looked into 1,375 families in the Oxford area where one or more children had diabetes and found that the risk of a child developing insulin-dependent diabetes increased by 25 percent for each five-year band of the mother's age. The risk of developing diabetes was also linked to the age of the father. For every five-year band of the father's age the risk of the child developing diabetes increased by nine percent. The risk of diabetes was highest among the firstborn children of mothers who started their families late and the risk decreased by about 15 percent for each subsequent child, the BMJ said. The older the mother, the earlier the start of insulin-dependent diabetes in the child. Other studies have already shown that children born to older mothers, over the age of 35, have an increased risk of diabetes but this study is the first to establish that risk increases continuously in relation to increasing maternal age, Dr. Polly Bingley of Southmead Hospital told Reuters (路透社). The new study is the first to show that risk is related to birth order. The study also partly explains increasing diabetes. Between 1970 and 1996 the proportion of children born to mothers aged between 30 and 34 increased to 28 percent from 15 percent and this could account for rising numbers of childhood diabetes patients, the scientists said in the BMJ. The diabetes charity Diabetes UK agreed that the study may have uncovered a reason for the alarming increase in the rate of (insulin-dependent) diabetes among children in recent years. 'This study may well provide a clue to the understanding of this problem. It is most likely that t. here are a number of factors to explain the increase,' Diabetes UK said. There are some 1.4 million diagnosed diabetes sufferers in Britain, the charity Diabetes UK said. Of these 1.4 million sufferers there are 20,000 people under age 20 who suffer from insulin-dependent diabetes. According to the passage, the risk of a child developing insulin-dependent diabetes is linked to all the following factors EXCEPT