英语语法分析

At the end of the first trimester, the fetus is about three inches long.

在怀孕的第三个月末，胎儿差不多有三英寸长了。

《柯林斯英汉双解大词典》

Especially during the final trimester.

特别是在怀孕终期。

See your eye doctor within the first trimester of pregnancy.

在怀孕的前三个月要去看眼科医生。