孕婦的壓力會影響男嬰健康大綱

Baby boys are more sensitive to stress in the womb

子宮中的男嬰對壓力更敏感

May explain why maternAl stress and disorders such as autism and schizophrenia are more common in boys

因受母體的壓力和精神失常因素影響，所以，如自閉症和精神分裂症在男孩中較常見

A pregnant women can transmit the damaging effects of stress to her unborn child through the placenta, say researchers.

研究人員說，孕婦壓力經胎盤對未出生嬰兒有破壞性影響。

Scientists believe it could explain known links between maternal stress and disorders such as autism and schizophrenia, which are more common and serious in male offspring.

科學家認爲因受母體的壓力和精神失常這些因素影響，所以，如自閉症和精神分裂症在男孩中較常見較嚴重。

'Almost everything experienced by a woman during a pregnancy has to interact with the placenta in order to transmit to the foetus,' said lead researcher Dr Tracy Bale, from the University of Pennsylvania’s School of Veterinary Medicine in the U.S.

幾乎女性懷孕期間所經歷的一切都會經胎盤傳遞給嬰兒，美國賓夕法尼亞大學獸醫學學院負責此項研究的特雷西·貝爾說。

'Now we have a marker that appears to signal to the foetus that its mother has experienced stress.'

現在我們研究發現胎兒的表現信號與母親所經歷的壓力因素有關。

The researchers studied female mice that were exposed to mild stresses such as the smell of foxes or unfamiliar noises during the first week of pregnancy. They identified an enzyme called OGT that was present at lower levels in the placentas of stressed mice than in unstressed mice.

經研究人員鑑定有壓力的小白鼠比沒有壓力的小白鼠胎盤內的一種稱爲轉移酶（OGT）的這種酶含量低。

Male offspring placentas also had lower natural levels of OGT than those attached to female offspring.

男性胎盤的轉移酶也比女性胎盤的轉移酶含量低。

Further research showed that cutting levels of OGT triggered changes in more than 370 genes in the brains of unborn mice.

進一步研究發現轉移酶含量降低引起了未出生小白鼠大腦中370個基因發生變化。

Many of these genes play a role in functions critical to neurological development, such as energy use, protein regulation and creating nerve cell connections.

這些基因對神經發育功能起到關鍵作用，如精神狀態、蛋白質調節、造神經細胞、連接神經細胞。

Analysis of human placentas discarded after the birth of male babies showed evidence of reduced OGT levels.

分析男嬰出生後的胎盤，結果表明轉移酶的含量降低了。

The results suggest that OGT may protect the brain during pregnancy. Males have less of the protein to begin with, placing them at greater risk if their mothers are stressed.

結果表明懷孕期間轉移酶可保護大腦，最開始男性蛋白質較少，如果母親有壓力就會對男嬰構成較大風險。

'We want to get to the point where we can predict the occurrence of neurodevelopmental disease,' said Dr Bale.

貝爾博士說，重點在於我們能預知神經發育疾病。

'If we have a marker for exposure, we can meld that with what we know about the genetic profiles that predispose individuals to these conditions and keep a close eye on children who have increased risks.'

如果我們發現這一跡象，再加上我們對基因結構的瞭解，預測個人對這些條件的瞭解並密切關注孩子們的風險增加情況。