Final answer:
Early decelerations should be done by the end of the second trimester of pregnancy, which occurs between weeks 13 to 28.
Step-by-step explanation:
Early decelerations should be done by the end of the second trimester of pregnancy, which occurs between weeks 13 to 28. During this trimester, the fetus grows larger and the mother can start feeling its movements by about week 20. The second trimester is characterized by increased energy levels and a decrease in symptoms like nausea and vomiting.