In addition to getting a much bigger belly, having morning (and sometimes afternoon and evening) sickness, there are other things that may change in your body. One of these may be your bowel movements.
Almost two thirds of women who are pregnant say they have to search for constipation relief to some extent.
One of the reasons for this is some of the hormone changes that are happening in the body. Once a woman gets pregnant, her body starts making large amounts of the hormone progesterone. This particular hormone has a slight muscle relaxing effect on the body. Often the digestive system is where this effect is seen, as it slows down the processing done by the intestines and digestive system, and leads to constipation.