During which part of pregnancy does the fetus begin to blink its eyes and become more active

The answer is In the last trimester of pregnancy. While the senses of the fetus start to develop in the 8th week, the different sense mature at different stages. Vision is the last sense to mature. After the 26th week, after the eyelids of the fetus have fully developed, the fetus begins to blink (even experience REM while involves rapid eyelid movements).