VOA标准英语2011--Hormone Could Restore Fertility in Lean

（单词翻译）

Hormone¹ Could Restore Fertility in Lean Women

Some women with very low body fat - such as athletes and professional dancers - stop menstruating and have an increased risk of bone fracture. Now, there's increasing evidence that hormone treatments can help these women.
The study involved young women with extremely low body fat and a condition called hypothalamic amenorrhea. It's part of a self-preservation mechanism² shared by many species: when the food supply is low, scarce energy is focused on survival, not reproduction.
"These women had stopped having their periods because they were exercising more than usual, or having stress, or a little bit of decreased food intake," says Sharon Chou, a researcher at Beth Israel Deaconess Medical Center in Boston.
In a new study, she and her colleagues tested whether a synthetic³ form of the hormone leptin could restore normal menstrual periods.
Leptin was discovered in 1994. It is related to the body's reserves of fat, so the hormone was investigated as a possible treatment to curb⁴ the appetites of obese⁵ people. That didn't work, but subsequent research found that leptin does play an important role in regulating how the body responds to lower food supplies.
Researchers found women with hypothalamic amenorrhea had low levels of leptin, and a 2004 study suggested that treatments with synthetic leptin (metreleptin) could restore menstruation. This latest research confirms that finding with a larger, more scientifically-rigorous study.
Nevertheless, Chou says the research is still a work in progress, so doctors won't be doing leptin treatments in the immediate⁶ future.
"But the idea is, these women can regain⁷ their menstrual cycle, menstrual function. And then, we're also looking to see if, used over a longer time period - perhaps one or two years - if these women would regain some of their bone loss."
The paper describing the effectiveness of leptin treatments by first author Sharon Chou, senior author Christos Mantzoros, and colleagues, is published online in the Proceedings⁸ of the National Academy of Sciences.