Pregnancy brings changes in your hormonal balance. And that can cause other symptoms..
Frequent urination. For many women, this starts around the sixth or eighth week after conception. Although this could be caused by a urinary tract infection, diabetes, or overusing diuretics, if you're pregnant, it's most likely due to hormonal levels.
Constipation. During pregnancy, higher levels of the hormone progesterone can make you constipated. Progesterone causes food to pass more slowly through your intestines. To ease the problem, drink plenty of water, exercise, and eat plenty of high-fiber foods.
Mood swings. These are common, especially during the first trimester. These are also related to changes in hormones.