US Officials: Twin Births Drop to Lowest Level in 10 Years

 

United States health officials say the number of twin births nationwide has dropped to their lowest level in 10 years.

The U.S. Centers for Disease Control and Prevention, CDC, reported the decrease. Twin births nationwide began to increase about 40 years ago, CDC records show. From 1980 until 2014, the total number rose 79 percent.

But from 2014 to 2018, the twin birth rates fell 4 percent. Last year, there were 32.6 twins for every 1,000 total births, the CDC reported.

While the latest drop was not huge, officials said they consider it a good sign. Pregnancy¹ with more than one child raises the risks of complications and death for both the mother and the baby.

Dmitry Kissin is a doctor who works with the CDC’s Division of Reproductive Health. He told The Associated Press that many people do not realize there can be serious risks with twin births.

“In the media,” he said, “there are often stories about very cute twins and talking about how great to have two babies at the same time.” Such stories ignore the health risks, Kissin added.

In 2018, about 124,000 babies born in the United States were twins. That represents about one in every 31 births.

Health experts say there is no single explanation for the falling twin birth rates.

However, Joyce Martin, the lead writer of the report, suggested one likely reason. She noted² that the falling rates were only among white women and in women 30 years of age or older. Women from these groups are the biggest users of in vitro fertility treatments.

In vitro fertilization is when doctors combine male and female cells to create an embryo³, which is later implanted in a woman’s uterus. This technique results in about 15 percent of all births involving more than one baby.

In the past, it was common for fertility experts to implant⁴ two or more embryos⁵ to improve the chances of a successful birth. This greatly increased the woman’s chances of having more than one baby.

In recent years, however, the method has changed. Fertility specialists now grow embryos longer in the lab and carry out more tests for genetic⁶ problems. They then choose the best single embryo to implant.

The CDC’s Dmitry Kissin says that today, about two-thirds of in vitro fertility treatments involve just one embryo.

Aaron Styer is an infertility⁷ treatment specialist in Chestnut⁸ Hill, Massachusetts. He told The AP the success rate for one embryo rose from about 20 percent in the 1980s to around 50 percent today.

Styer said that health insurance companies and medical organizations have increasingly been pushing doctors to implant just a single embryo. More and more patients are also accepting the method to improve their chances of a successful pregnancy, he added.

I’m Bryan Lynn.

Words in This Story

twin – n. one of two children born to the same mother at the same time

complication – n. something that makes a situation more difficult

cute – adj. having a pleasing and usually youthful appearance

embryo – n. an animal or human being in the early days of development

uterus – n. a muscular organ in the female mammal for carrying the young while it develops inside her body

insurance – n. a process in which a company or government agency provides a guarantee of payment for losses or damages

1 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。

2 noted   

adj.著名的，知名的

参考例句：

• The local hotel is noted for its good table.当地的那家酒店以餐食精美而著称。
• Jim is noted for arriving late for work.吉姆上班迟到出了名。

3 embryo   

n.胚胎，萌芽的事物

参考例句：

• They are engaging in an embryo research.他们正在进行一项胚胎研究。
• The project was barely in embryo.该计划只是个雏形。

4 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。

5 embryos   

n.晶胚；胚，胚胎( embryo的名词复数 )

参考例句：

• Somatic cells of angiosperms enter a regenerative phase and behave like embryos. 被子植物体细胞进入一个生殖阶段，而且其行为象胚。 来自辞典例句
• Evolution can explain why human embryos look like gilled fishes. 进化论能够解释为什么人类的胚胎看起来象除去了内脏的鱼一样。 来自辞典例句

6 genetic   

adj.遗传的，遗传学的

参考例句：

• It's very difficult to treat genetic diseases.遗传性疾病治疗起来很困难。
• Each daughter cell can receive a full complement of the genetic information.每个子细胞可以收到遗传信息的一个完全补偿物。

7 infertility   

n.不肥沃，不毛；不育

参考例句：

• It is the Geneva, Switzerland-based Biotech Company's second recombinant infertility drug. 它是瑞士生物技术公司在日内瓦的公司生产的第二种重组治疗不孕症的药。 来自英汉非文学 - 生命科学 - 生物技术制药疫苗
• Endometritis is a cause of infertility. 子宫内膜炎是不育的原子。 来自辞典例句

8 chestnut   

n.栗树，栗子

参考例句：

• We have a chestnut tree in the bottom of our garden.我们的花园尽头有一棵栗树。
• In summer we had tea outdoors,under the chestnut tree.夏天我们在室外栗树下喝茶。