美國羅徹斯特大學(xué)醫(yī)學(xué)中心(University of Rochester Medical Center)的研究團隊,，調(diào)查了387位在2000到2005年懷孕的婦女,，發(fā)現(xiàn)在懷孕期間攝取大量牛肉(每周吃超過七份牛肉)的婦女，其兒子的精蟲濃度會比一般標(biāo)準(zhǔn)值低24.3%,，其中有18%的人被WHO判定為不孕(sub-fertile),。研究人員認為罪魁禍?zhǔn)讘?yīng)是飼養(yǎng)牛只的飼料或飼草含有的殺蟲劑、污染物,，或飼主為了使牛只快速生長而施打的荷爾蒙,。此研究發(fā)表于Human Reproduction期刊,。
Shanna Swan博士說：「雖然在研究中發(fā)現(xiàn)懷孕婦女吃大量牛肉會導(dǎo)致其子的精蟲濃度降低的現(xiàn)象，但這個現(xiàn)象仍需持續(xù)仔細的追蹤及分析,，才能有所結(jié)論,，因為男子的精蟲濃度過低可能和很多因子都有相關(guān)性?！共贿^,，一份先前在動物模式的研究中，的確已證實環(huán)境荷爾蒙會降低動物的精蟲數(shù)目,。
這項研究從2000年就開始進行,，研究人員設(shè)計了一些問卷給那些精蟲受測者的母親填寫，Swan自己也承認這份研究在某些程度上是有瑕疵的,，因為許多的數(shù)據(jù)來源是藉由這些母親們回憶而得到的,，不過，Swan也確信,，大部份的懷孕婦女都會特別留意什么食物該吃或吃的最多,。Swan研究團隊接下來要調(diào)查的對象，是住在歐盟的年輕男性,，因為歐盟在1988年就禁止在牛只身上施打荷爾蒙。藉由這些后續(xù)的研究來驗證懷孕婦女吃牛肉與其子精蟲數(shù)減少之間的關(guān)聯(lián)性,。 (資料來源 : Reuters)
英文原文：
Eat a lot of beef? It may affect your son's sperm
Wed Mar 28, 2007 3:55AM EDT
By Maggie Fox, Health and Science Editor
WASHINGTON (Reuters) - U.S. women who eat a lot of beef while pregnant give birth to sons who grow up to have low sperm counts, researchers reported on Tuesday.
They believe pesticides, hormones or contaminants in cattle feed may be to blame. Chemicals can build up in the fat of animals that eat contaminated feed or grass, and cattle were and are routinely given hormones to boost their growth.
"In sons of 'high beef consumers' (more than seven beef meals/week), sperm concentration was 24.3 percent lower," the researchers wrote in their report, published in the journal Human Reproduction.
The team at the University of Rochester Medical Center in New York studied data on the partners of 387 pregnant women in five U.S. cities between 2000 and 2005, and on the mothers of the fathers-to-be.
Of the 51 men whose mothers remembered eating the most beef, 18 percent had sperm counts classified by the World Health Organization as sub-fertile.
"The average sperm concentration of the men in our study went down as their mothers' beef intake went up. But this needs to be followed carefully before we can draw any conclusions," said Shanna Swan, who led the team.
Swan said she would like to study infertile men to see if similar findings might hold for them.
"I was really surprised when we found this. It was a really strong association," Swan said in a telephone interview.
Swan is perhaps best known for controversial findings that male sperm counts are falling in many regions. She has been doing research to find out if environmental hormones may be to blame.
"We know from rodent studies that even tiny amounts of estrogen in utero (while in the womb) can affect sperm count," Swan said.
