Final answer:
During the third trimester, mild swelling in the ankles and occasional heartburn after meals are common, but sudden and severe abdominal pain is not and should be reported to the doctor immediately.
Step-by-step explanation:
During the third trimester of pregnancy, a woman may experience a range of symptoms due to the expanding uterus and the growing fetus. It is crucial to know which symptoms are typical and which require immediate medical attention. Mild swelling in the ankles is a common occurrence due to increased blood volume and circulation changes. However, while occasional heartburn after meals and normal fetal movement patterns are also to be expected, sudden and severe abdominal pain is a potential indicator of a serious problem and should be reported to the doctor immediately.