1998 From: New Scientist
Natural Childbirth Could Play A Role In Brain DevelopmentCAESAREAN babies may be more susceptible to schizophrenia than children born naturally, say Canadian researchers who studied the effects of the operation on rats. The finding raises doubts about the increasing number of Caesarean sections performed for convenience. Patricia Boksa and Bassem El-Khodor of McGill University in Montreal gave pregnant rats general anaesthetics and delivered their young by Caesarean section. The operations were uncomplicated and the rat pups appeared normal at birth. But they grew into adults with marked differences compared with controls born naturally. "To our surprise, we kept finding dopamine system differences," says Boksa. When the Caesarean rats were given amphetamines, for instance, drugs that activate the dopamine system in the brain, they became far more active than the other group, the researchers told last week's meeting. The Caesarean rats also had a far worse response to repeated tail pinching, a standard test for stress reactions. The results hint that babies born by Caesarean may be more vulnerable to schizophrenia, which is thought to involve an overactive dopamine system and has a statistical link with birth complications. But no one knows why a Caesarean birth might increase the risk of developing the illness. Boksa thinks the absence of hormonal surges when a baby is born naturally may play a role, because these may be important for brain development. Boksa says we need more evidence about the operation's effects. "I would question the Caesarean section of convenience," she says. "There's a lot of discussion about complications precipitating schizophrenia in genetically vulnerable people," says Barbara Fish of the University of California at Los Angeles, who studies the effects of difficult births. But she cautions that it is difficult to draw conclusions from the studies when many environmental factors are involved. Author: Alison Motluk New Scientist , issue 21st Nov. 98 PLEASE MENTION NEW SCIENTIST AS THE SOURCE OF THIS ARTICLE - THANK YOU UK CONTACT - Claire Bowles, New Scientist Press Office, London: Tel: 44-171-331-2751 or email [email protected] US CONTACT - Barbara Thurlow, New Scientist Washington office: Tel: 202-452-1178 or email [email protected]
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