Symptoms may not start for 6 to 12 hours after exposure to the ultraviolet light. Symptoms include: 1  A feeling that something is in the eyes (foreign body sensation). 2  Sensitivity to light (photophobia). 3  Tearing.
It is divided into three stages, called trimesters: first trimester, second trimester, and third trimester. Conception to about the 12th week of pregnancy marks the first trimester. The second trimester is weeks 13 to 27, and the third trimester starts about 28 weeks and lasts until birth.
Pregnancy can be divided into weeks and sometimes days. A pregnancy that is â36 and 3/7 weeksâ means â36 weeks and 3 days of pregnancy.â The 40 weeks of pregnancy often are grouped into three trimesters. Each trimester lasts about 12â13 weeks (or about 3 months): First trimester: 0 weeksâ13 and 6/7 weeks (Months 1â3)