21世纪，英语已经走进了我们每个人的生活，学好英语成了我们共同的目标，为了帮助大学生更好地掌握英语，特提供以下文章：
曩昔年夜夫认为试管婴儿是一种很好的辅佐不孕不育的佳耦圆孩子梦的体例。但此刻，这种体例需要三思尔后行。现代医学证实，试管婴儿也许比正常怀孕出产的孩子罹患先天或后天疾病的可能性更年夜。
Do infertility treatments damage babies'genes? Doctors used to think not.Now they are not so sure.
治疗不孕损害婴儿的遗传基因吗?年夜夫们曩昔认为不会有什媚暌拱响，此刻他们对此不十分必定了。
In the 24 years since the birth of Louise Brown，the world's first test-tube baby，thousands of would-be parents have been assure that as far as scientists knew there was no extra risk of genetic damage associated with in-vitro fertilization，or IVF.No matter how sperm meets egg--whether in a woman's body or in a Petri dish(and even if the sperm needs some help getting inside the egg)--nature is equally vigilant about preventing serious genetic mishaps from coming to term.With those assurances，test-tube births have soared from a few hundred a year in the early 1980s to tens of thousands today.
世界首例试管婴儿路易斯·布朗出生后24年的时刻里，成千上万想做怙恃亲的人们获得科学家们的保证说，试管内受精对基因不会有什么额外的危险。无论精子若何与卵子连系--是否在女人体内仍是在较硬的试管壁上，(即使精子需外力辅佐才与卵子连系)，年夜自然都同样会阻止严重变形的基因临蓐，有了这样的允诺和保证，试管婴儿的出生在20世纪80年月早期由每年的百余例上升到现现在的数万例。
But according to a pair of reports in last week's New England Journal of Medicine，that conventional wisdom may be wrong.In the first study，doctors in Britain and Australia found that infants conceived with both straightforward test-tube methods and a more invasive technique called intra-cytoplasmic sperm in jection，in which sperm is injected directly into the egg，have an 8.6% risk of major birth defects--including heart and kidney abnormalities，cleft palate and undescended testicles -- compared with the 4.2% rate in babies made the old-fashioned way.The second study，conducted by the U.S.Centers for Disease Control and Prevention(CDC)，reported that babies conceived through what doctors call assisted reproductive technologies(ART)have 2.6 times the risk of low or very low birth weight --a significant risk factor for cardiac and cognitive problems.
但上周的《新英格兰医学杂志》有两篇陈述指出：这种传统的说法也许是错误的。在第一篇研究陈述中，英国和澳年夜利亚的年夜夫们发现，直接的试管受精和经由过程更具侵人道的手艺--把精液经由过程打针直接与卵子相遇的体例而出生的婴儿，有8.6%存在着首要由出生造成的缺陷的危险性--搜罗心脏、肾功能不正常、裂腭、男孩隐睾症等。而正常受孕出生的孩子这种现象的比率只为4.2%。第二个研究陈述是由美国疾病节制与预防中心主持作出的。陈述指出，经由过程年夜夫们所谓协助生育手艺的体例而受孕出生的婴儿出生时低体重或严重低体重的危险是正常情形的2.6倍。这是引起心脏病和认知能力问题的危险身分。