Women who have ever been around smokers regularly may have more difficulty getting pregnant than those who have not, a new study suggests. The findings, researchers say, offer one more reason for women to kick the smoking habit.
Studies have found that women who smoke raise their risk of a number of pregnancy complications, as well as their infants' risk of health problems. Less is known about the dangers of secondhand smoke, though some studies have linked exposure during pregnancy to an elevated risk of miscarriage.

In the new study, of more than 4,800 women, researchers found those who'd grown up with a parent who smoked were more likely to report they'd had difficulty becoming pregnant — defined as having to try for more than 1 year.

In addition, women who'd been exposed to secondhand smoke in both childhood and adulthood were 39 percent more likely to have suffered a miscarriage or stillbirth, and 68 percent more likely to have had problems getting pregnant.

"These statistics are breathtaking and certainly (point) to yet another danger of secondhand smoke exposure," said lead researcher Luke J. Peppone at the University of Rochester, New York.

"We all know that cigarettes and secondhand smoke are dangerous," he added. "Breathing the smoke has lasting effects, especially for women when they're ready for children."

Peppone and his colleagues at the University of Rochester in New York report their findings in the December 5 online issue of the journal Tobacco Control.

For the study, the researchers analyzed surveys from 4,804 women who'd visited the university's Roswell Park Cancer Institute between 1982 and 1998 for health screening or cancer treatment. All had been pregnant at least once in their lives.

Overall, Peppone's team found 11 percent of the women had difficulty becoming pregnant, while one third had a miscarriage or stillbirth.

The risk of these problems tended to climb in tandem with the number of hours per day that a woman was exposed to secondhand smoke — a pattern that suggests a cause-effect relationship.

Secondhand smoke contains a host of toxic compounds that could potentially harm a woman's reproductive health, Peppone and his colleagues note. Tobacco toxins may damage cells' genetic material, interfere with conception, raise the risk of miscarriage, or inhibit the hormones needed for conception and a successful pregnancy.

一项新的研究显示,经常被动吸烟的女性比正常女性更难受孕。研究人员称,这项研究结果将有助于女性戒掉吸烟恶习。

研究发现,孕妇吸烟会增加患孕期并发症的可能性,由此孩子的健康也会受损。对于孕妇吸二手烟的危害性还有待进一步研究,但有些研究显示,孕期被动吸烟会增加流产的可能性。

一项由4,800多人参与的研究表明,有吸烟史人的子女更有可能经过1年以上的尝试也不易怀孕。

此外,从儿时到成年时期都吸二手烟的女性有39%在怀孕期间更容易导致流产或死胎,68%的人很难受孕。

研究小组组长,纽约罗彻斯特大学的卢克.杰.派鹏介绍说,“这些数据触目惊心,证明了二手烟带来的又一风险。”

“我们都知道吸烟和被动吸烟有害健康,吸入的烟会产生一个长期的影响,尤其对于那些准备怀孕的女性影响更多。”

12月5日,派鹏和他的研究小组在《烟草控制杂志》上刊登了研究报告。

研究人员对4,804位于1982年至1998年期间到Roswell Park肿瘤医院进行身体检查或接受治疗的女性患者情况进行了分析,这些女性都至少有过一次怀孕的经历。

派鹏小组研究发现,其中11%的女性难以受孕,三分之一的女性有过流产或死胎的经历。

女性被动吸二手烟,上述问题发生的危险性与时俱增—这已经形成了一种原因-结果的关系模式。

派鹏和他的研究小组指出,二手烟包含一系列有毒成份,可能会潜在地损伤女性生殖健康。烟草毒素会破坏细胞遗传物质,影响受孕,增加流产的风险性,以及阻止成功受孕所需荷尔蒙的分泌。