美国国家公共电台 NPR Even Low-Dose Contraceptives Slightly Increase Breast Cancer Risk

 

MARY LOUISE KELLY, HOST:

New research finds an increased risk of breast cancer among women who are using hormonal¹ birth control. The study's published in The New England Journal of Medicine, and NPR's Patti Neighmond has our report.

PATTI NEIGHMOND, BYLINE²: Scientists have long known contraceptives that contain estrogen can increase the risk of breast cancer. But researchers in Denmark looked at 1.8 million women between the ages of 15 and 49 to see if new lower-dosed formulations are still risky³. They compared what happened over nearly 11 years among women taking hormonal birth control and women using other methods. Epidemiologist Lina Morch headed the study.

LINA MORCH: We found approximately a 20 percent increased risk among women who currently use some type of hormonal contraception.

NEIGHMOND: Hormonal contraception releases estrogen, progestin or a combination of both to suppress ovulation and prevent pregnancy⁴. Mia Gaudet with the American Cancer Society says the findings are compelling because researchers didn't just look at the birth control pill. They looked at all birth control methods that release hormones⁵.

MIA GAUDET: Including the patch, the ring, the implant⁶, as well as IUD.

NEIGHMOND: All of these forms of hormonal contraception increased breast cancer risk by 20 percent. And the longer women used this type of birth control, the more breast cancer risk increased. The findings are disappointing, says epidemiologist David Hunter with the University of Oxford⁷. Over the past few decades, researchers tried to develop new hormonal formulas using less estrogen, which is known to promote breast cancer. The hope was the lower dose would decrease breast cancer risk. But that's not what this study found.

DAVID HUNTER: Unfortunately, the increase of 20 percent appears to apply to the most recent formulations just like it did in the '70s, '80s and '90s. So this tells us that things haven't changed.

NEIGHMOND: Lead researcher Morch says the findings should serve as a caution but not an alarm. A 20 percent increase translates into only one extra breast cancer case for nearly every 8,000 women. It's even lower among younger women since breast cancer in this age group is relatively⁸ rare.

MORCH: So it has to be balanced - the pros⁹ and cons¹⁰ of these contraceptives. And if it's not needed to take hormonal contraceptions, it might be worth considering using other methods like the copper¹¹ IUD or barium if it's - like condoms, for instance.

NEIGHMOND: Now, it's important to note in the study, women over 40 were more likely to suffer breast cancer than younger women in their 20s and 30s. Age, family history and weight gain later in life all contribute to breast cancer risk. Morch suggests women over 40 discuss possible alternatives with their doctor. And epidemiologist Hunter says there are other clear benefits of hormonal contraception.

HUNTER: There's very good evidence that oral contraceptives reduce the risk of ovarian cancer. They reduce the risk of endometrial cancer. There's a strong suggestion they actually reduce the risk of colorectal cancer. And so many calculations suggest that use of all contraceptives actually prevents more cancers than it causes.

NEIGHMOND: Hunter says the search for new hormonal contraceptives that don't elevate breast cancer risk should continue. Patti Neighmond, NPR News.

1 hormonal   

adj.激素的

参考例句：

• Some viral diseases are more severe during pregnancy, probably tecause of hormonal changes. 有些病毒病在妊娠期间比较严重，可能是由于激素变化引起的。
• She underwent surgical intervention and a subsequent short period of hormonal therapy. 他接受外科手术及随后短暂荷尔蒙治疗。

2 byline   

n.署名；v.署名

参考例句：

• His byline was absent as well.他的署名也不见了。
• We wish to thank the author of this article which carries no byline.我们要感谢这篇文章的那位没有署名的作者。

3 risky   

adj.有风险的，冒险的

参考例句：

• It may be risky but we will chance it anyhow.这可能有危险，但我们无论如何要冒一冒险。
• He is well aware how risky this investment is.他心里对这项投资的风险十分清楚。

4 pregnancy   

n.怀孕，怀孕期

参考例句：

• Early pregnancy is often accompanied by nausea.怀孕早期常有恶心的现象。
• Smoking during pregnancy increases the risk of miscarriage.怀孕期吸烟会增加流产的危险。

5 hormones   

n. 荷尔蒙，激素 名词hormone的复数形式

参考例句：

• This hormone interacts closely with other hormones in the body. 这种荷尔蒙与体內其他荷尔蒙紧密地相互作用。
• The adrenals produce a large per cent of a man's sex hormones. 肾上腺分泌人体的大部分性激素。

6 implant   

vt.注入，植入，灌输

参考例句：

• A good teacher should implant high ideals in children.好教师应该把高尚理想灌输给孩子们。
• The operation to implant the artificial heart took two hours.人工心脏植入手术花费了两小时。

7 Oxford   

n.牛津（英国城市）

参考例句：

• At present he has become a Professor of Chemistry at Oxford.他现在已是牛津大学的化学教授了。
• This is where the road to Oxford joins the road to London.这是去牛津的路与去伦敦的路的汇合处。

8 relatively   

adv.比较...地，相对地

参考例句：

• The rabbit is a relatively recent introduction in Australia.兔子是相对较新引入澳大利亚的物种。
• The operation was relatively painless.手术相对来说不痛。

9 pros   

abbr.prosecuting 起诉；prosecutor 起诉人；professionals 自由职业者；proscenium （舞台）前部n.赞成的意见( pro的名词复数 )；赞成的理由；抵偿物；交换物

参考例句：

• The pros and cons cancel out. 正反两种意见抵消。 来自《现代英汉综合大词典》
• We should hear all the pros and cons of the matter before we make a decision. 我们在对这事做出决定之前，应该先听取正反两方面的意见。 来自《简明英汉词典》

10 cons   

n.欺骗，骗局( con的名词复数 )v.诈骗，哄骗( con的第三人称单数 )

参考例句：

• The pros and cons cancel out. 正反两种意见抵消。 来自《现代英汉综合大词典》
• We should hear all the pros and cons of the matter before we make a decision. 我们在对这事做出决定之前，应该先听取正反两方面的意见。 来自《简明英汉词典》

11 copper   

n.铜；铜币；铜器；adj.铜(制)的；(紫)铜色的

参考例句：

• The students are asked to prove the purity of copper.要求学生们检验铜的纯度。
• Copper is a good medium for the conduction of heat and electricity.铜是热和电的良导体。