What might frequent urination in the third trimester indicate?

Frequent urination in the third trimester is often associated with fetal engagement in the pelvis. As the pregnancy progresses, the growing fetus exerts increased pressure on the bladder, especially when the baby descends into the pelvic cavity in preparation for birth. This engagement can lead to a sensation of needing to urinate more frequently, as the capacity of the bladder becomes compromised by the presence of the engaged fetus.

Other factors related to urination during pregnancy may include hydration levels, but that does not specifically explain the increased frequency in the third trimester; hydration would generally affect urine output but not specifically the urge to urinate more often. Low blood sugar levels and kidney function problems are less directly related to the common experience of frequent urination in late pregnancy and are more indicative of other health issues. Therefore, the correct answer focuses on the relationship between fetal positioning and the physical changes occurring in a woman's body as she approaches labor.