The effect in the second trimester of pregnancy was most marked.

在怀孕的第4-6个月时影响最为显著。

youdao

These severe leg cramps usually pop up in the second trimester and continue through the third.

这种严重的腿部肌肉抽筋现象通常出现在怀孕中期，并持续整个怀孕后期。

youdao

The second trimester is coming to an end and your body is gearing up for the prenatal homestretch.

怀孕中期马上就要结束了，你的身体正在做产前的最后准备。

youdao

And so we are proposing to give this pouch to mothers in their first or second trimester, when they come in for their first antenatal care visit.

VOA: special.2010.05.24

Some states have no time limit, while others allow abortion up to the end of the second trimester, about 27 or 28 weeks into the pregnancy.

CNN: North Dakota governor signs law banning most abortions

To get human retinal cells at the same stage of development, however, would involve taking stem cells from a foetus during the second trimester of pregnancy.

BBC: NEWS | Health | Cell transplants 'restore sight'

It usually ends by the second trimester.

NPR: FDA Approves Return Of Drug For Morning Sickness