Babies should sleep in their mother’s bed until they are at least three years old, it was claimed last night。

　　The controversial advice comes from a paediatrician who found that two-day-old babies who were placed in cots slept less well than those who dozed on their mother’s chest。

　　Their hearts were also under more stress, it was claimed。

　　Sleeping alone makes it harder for mother and child to bond - and damages the development of the brain, leading to bad behaviour as the child grows up, researchers fear。

　　Dr Nils Bergman, of the University of Cape Town, South Africa, says that for optimal development, healthy newborns should sleep on their mother’s chest for the first few weeks。

　　After that, they should stay in the mother’s bed until they are three or even four years old。

　　However, studies linking bed-sharing with an increased risk of cot death and fears that a mother will roll over and smother her child means that women are generally advised against this。

　　In a recent British study of sudden infant deaths, almost two-thirds of those that were unexplained occurred when the bed was being shared。

　　But Dr Bergman said: ‘When babies are smothered and suffer cot deaths, it is not because their mother is present. It is because of other things: toxic fumes, cigarettes, alcohol, big pillows and dangerous toys.’

　　Sixteen infants were studied while they slept on their mother’s chest and in a cot by her bed. Monitoring revealed the baby’s heart to be under three times as much stress when he or she slept alone。

　　Being in a cot also disrupted sleep, with the babies’ brains less likely to ‘cycle’ or make the transition between two types of sleep called active and quiet。

　　In the cots, only six out of the 16 had any quiet sleep and its quality was far worse。

　　Making this transition is thought to be key to the normal development of the brain。

　　Animal studies have linked the combination of stress and lack of sleep to behavioural problems in teenage years。

　　Dr Bergman said that changes to the brain brought on by stress hormones may make it more difficult to form relationships later on, leading to problems such as promiscuity。

　　昨晚发布的研究报告称，至少要到三岁大，宝宝才能和妈妈分床睡。

　　提出这一争议性建议的是一名小儿科医生，这名医生发现，在婴儿床里睡觉的两岁大的宝宝睡眠质量比睡在妈妈胸口的宝宝要差。

　　而且，据称，睡婴儿床的宝宝的心脏要承受更大的压力。

　　研究人员担心宝宝单独睡不利于母子之间建立感情纽带，而且会损害大脑的发育，导致孩子成长过程中的不良行为。

　　南非开普敦大学的尼尔斯•伯格曼医生说，为了让孩子的成长最优化，健康的新生儿在头几周应该睡在妈妈的胸口。

　　此后，一直到三岁甚至四岁，他们都应该和妈妈同床睡。

　　然而，有研究认为宝宝和妈妈同床睡会增加婴儿猝死风险，担心妈妈翻身会压到宝宝，让宝宝窒息，因此一般建议女性不要和宝宝同床睡。

　　近日英国一项针对婴儿猝死的研究指出，近三分之二的不明猝死事件都是在和母亲同床睡时发生的。

　　不过伯格曼医生说：“宝宝窒息和猝死不是因为妈妈在身边，而是因为其他因素：比如有毒气体、香烟、酒精、大枕头和危险的玩具等等。”

　　该研究观察了16名婴儿在母亲胸口睡觉和在母亲床边的婴儿床睡觉的情况。监测记录显示，婴儿在单独睡时心脏承受的压力是和母亲同床睡的三倍。

　　在婴儿床中睡觉还会扰乱婴儿的睡眠，这样婴儿的大脑就比较无法适应“周期”，不能在动态睡眠和静态睡眠两种模式中切换。

　　在婴儿床中，16名婴儿中只有6名可以有静态睡眠，而且睡眠质量也相对差得多。

　　在动态和静态睡眠之间切换被认为对大脑正常发育很关键。

　　动物研究曾将压力大和睡眠不足并存的状况与青少年时期的行为问题联系在一起。

　　伯格曼医生说，压力荷尔蒙引起的大脑的变化可能会让孩子日后更难建立感情关系，并可能导致性乱交这样的问题。