VOA标准英语2010年-Birth Delivery Method Gives Babies Dif

Around the world, cesarean births are on the rise, and many experts think that's a bad thing. Now, a new study looks at one way that babies delivered by c-section are different.

The number of surgical¹ deliveries has been increasing for years. Some cesareans are medically necessary. But in other cases, women just want the convenience of knowing when they will give birth. For some, it's the modern thing to do.

Doctors like that predictability, too. And health care providers usually charge more.

A World Health Organization survey of hospital and clinic births in nine Asian countries earlier this year found 27 percent were c-sections, and in China it was nearly half of all births. And there were more deaths and complications when women had a cesarean delivery that wasn't medically required.

Other research has found c-section babies are more likely to have asthma² or allergies³.

Now, a small but intriguing⁴ new study looks at one way the delivery method might affect the baby's health. Co-lead author Elizabeth Costello, now at Stanford, was at the University of Colorado when the study was done.

"We were looking at effect of delivery mode on the very first bacteria that the baby is exposed to," Costello explained. "So we sampled babies literally⁵ seconds and minutes after they were delivered. So we're only looking at a snapshot of that very first moment in time.

To do that, Costello's co-lead researcher Maria Dominguez-Bello of the University of Puerto Rico took samples of bacteria from mothers and babies immediately before and after birth. Women who gave birth vaginally transferred the unique mix, their unique "community" of vaginal bacterial⁶ to the newborn baby.

"And that was in direct contrast with the c-section babies, who harbored bacterial communities that resembled human skin, but not their own mother's human skin any more than any of the other mothers in the study."

The researchers suspect that the newborn c-section babies might be picking up their generic⁷ bacteria mix from the air - one way bacteria gets on our skin.

Exactly how the differences in bacteria might make vaginally born babies less prone⁸ to allergies and asthma isn't yet clear, but it does point to a difference that researchers can look at going forward. Costello says she expects more studies as DNA⁹ analysis gets cheaper and faster.

So, does Costello's study support the notion that vaginal birth is somehow "better" than a cesarean? Speaking via Skype, she says no.

"I think further studies will be necessary to show whether the differences we've demonstrated depending on delivery mode of babies when they first emerge into the world actually carry over time, and whether those differences might contribute to health outcomes."

Elizabeth Costello's paper is published online by the Proceedings¹⁰ of the National Academy of Sciences.

 

1 surgical   

adj.外科的，外科医生的，手术上的

参考例句：

• He performs the surgical operations at the Red Cross Hospital.他在红十字会医院做外科手术。
• All surgical instruments must be sterilised before use.所有的外科手术器械在使用之前，必须消毒。

2 asthma   

n.气喘病，哮喘病

参考例句：

• I think he's having an asthma attack.我想他现在是哮喘病发作了。
• Its presence in allergic asthma is well known.它在过敏性气喘中的存在是大家很熟悉的。

3 allergies   

n.[医]过敏症；[口]厌恶，反感；（对食物、花粉、虫咬等的）过敏症( allergy的名词复数 )；变态反应，变应性

参考例句：

• Food allergies can result in an enormous variety of different symptoms. 食物过敏会引发很多不同的症状。 来自辞典例句
• Let us, however, examine one of the most common allergies; hayfever. 现在让我们来看看最常见的变态反应的一种--枯草热。 来自辞典例句

4 intriguing   

adj.有趣的；迷人的v.搞阴谋诡计(intrigue的现在分词)；激起…的好奇心

参考例句：

• These discoveries raise intriguing questions. 这些发现带来了非常有趣的问题。
• It all sounds very intriguing. 这些听起来都很有趣。 来自《简明英汉词典》

5 literally   

adv.照字面意义，逐字地；确实

参考例句：

• He translated the passage literally.他逐字逐句地翻译这段文字。
• Sometimes she would not sit down till she was literally faint.有时候，她不走到真正要昏厥了，决不肯坐下来。

6 bacterial   

a.细菌的

参考例句：

• Bacterial reproduction is accelerated in weightless space. 在失重的空间，细菌繁殖加快了。
• Brain lesions can be caused by bacterial infections. 大脑损伤可能由细菌感染引起。

7 generic   

adj.一般的，普通的，共有的

参考例句：

• I usually buy generic clothes instead of name brands.我通常买普通的衣服，不买名牌。
• The generic woman appears to have an extraordinary faculty for swallowing the individual.一般妇女在婚后似乎有特别突出的抑制个性的能力。

8 prone   

adj.(to)易于…的，很可能…的；俯卧的

参考例句：

• Some people are prone to jump to hasty conclusions.有些人往往作出轻率的结论。
• He is prone to lose his temper when people disagree with him.人家一不同意他的意见,他就发脾气。

9 DNA   

(缩)deoxyribonucleic acid 脱氧核糖核酸

参考例句：

• DNA is stored in the nucleus of a cell.脱氧核糖核酸储存于细胞的细胞核里。
• Gene mutations are alterations in the DNA code.基因突变是指DNA密码的改变。

10 proceedings   

n.进程，过程，议程；诉讼(程序)；公报

参考例句：

• He was released on bail pending committal proceedings. 他交保获释正在候审。
• to initiate legal proceedings against sb 对某人提起诉讼