In one study, use of birth control pills led to a higher risk of premenopausal breast cancer in women who took the pill for four or more years before having a baby.

一项研究显示，在生育前使用口服避孕药达10年或以上，可导致绝经前乳腺癌风险增加。

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We enrolled for NCT classes: four or five couples sitting round on bean bags, all questing for the perfect birth.

我们加入了NCT课程：4 - 5对夫妻坐在豆子袋上，围在一堂，提些如何顺产的问题。

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They were assessed for symptoms of depression and anxiety twice during their pregnancy and four times after giving birth, at 8 weeks, 8 months, 21 months and 33 months.

这些女性大部分在怀孕期间产生2次抑郁和焦虑的症状，而在生产之后产生了4次症状，分别在生产的8个星期、8个月、21个月以及33个月之后。

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For example, four of the seven biggest manufacturers of birth control drugs and devices donated to a trade association supporting Republicans who were presumably pro-business, but who had also vowed to limit access to birth control-related products.

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The birth of her fourth child, Liza, left her unconscious for four days and prevented her having more children.

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The last ended in 1958 when the Liberals and Conservatives set up the National Front in which they agreed to rotate power between them every four years, excluding other political parties and so giving birth to the insurgency and the current civil conflict that has raged for four decades.

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