Which of the following is a common discomfort during the first trimester of pregnancy?

Morning sickness is a common discomfort experienced during the first trimester of pregnancy, affecting a significant number of pregnant individuals. This condition typically involves nausea and vomiting, particularly in the morning, but it can occur at any time of the day. The occurrence of morning sickness is attributed to hormonal changes, especially the increase in human chorionic gonadotropin (hCG) and estrogen, as well as physical and emotional adjustments that the body goes through in early pregnancy.

While back pain, heartburn, and leg cramps can occur during pregnancy, they are more commonly associated with later stages. Back pain might be more typical in the second and third trimesters due to the growing uterus and increased weight. Heartburn often arises later in pregnancy as the uterus expands and places pressure on the stomach, leading to acid reflux. Leg cramps are also more prevalent in the later stages as physical changes and pressure on blood vessels occur. Therefore, morning sickness is distinctly recognized as a hallmark symptom of the first trimester.