However, the nipples and areolas are not colored and the nipples are not sensitive, for example, when touched by hand, the nipples become erect, which is not a symptom before menstruation. However, after pregnancy, the estrogen in the body increases thousands of times, causing the breasts to enlarge and become mildly swollen and painful, and the breasts are very soft to the touch, mainly due to the action of estrogen, and the nipples and areolas become colored, and the nipples are particularly sensitive, and if touched with the hands, they become erect. This is the difference between regular and pregnant breasts.