Like most other symptoms of
pregnancy, these food preferences can be chalked up to hormonal changes — especially in the
first trimester, when hormone changes are the most dramatic.
Headaches
Early in pregnancy, increased blood circulation caused by hormonal changes may trigger frequent, mild headaches.
Constipation
Constipation is another common early symptom of pregnancy. An increase in progesterone causes food to pass more slowly through the intestines — which can lead to constipation.