The third trimester of pregnancy typically begins around week 28 and lasts until the birth of the baby. This is an important phase when both the mother and baby experience significant growth and development. During this time, the baby's organs continue to mature, and they start gaining weight rapidly. The mother may also notice increased discomfort due to the growing size of her belly, along with symptoms like back pain, frequent urination, and shortness of breath. Regular prenatal check-ups become even more crucial during this period to monitor the health and progress of both mother and baby. It's important for expectant mothers to take care of their physical and emotional well-being during this final stretch of pregnancy.