1 Both these new developments cause frequent urination during pregnancy. 2  This adds to the feeling of dehydration and dryness of the mouth in pregnancy. 3  Dry mouth at night during pregnancy could also be the result of some kind of health condition. 4  Dry mouth in pregnancy is not a disease but a symptom.
(June 2015). In the United States, the academic year typically has about 180 school days for K-12, running from the early in the Northern Hemisphere fall to early summer.
Iran is another nation in the northern hemisphere with a school year similar to European countries. Students in Iran go to school for 10 months a year, or about 200 active days, from September to June. The average number of students per classroom is 27. From ages 5 to 18, boys and girls are educated separately.