How does the fetus change between the third and sixth months f pregnancy?

Between the third and sixth months of pregnancy, the fetus undergoes significant growth and development. By the end of the third month, the fetus is about 3 inches long and has developed most of its major organs and structures. During the fourth to sixth months, it experiences rapid growth, increasing in size to approximately 12 inches by the sixth month, and begins to develop more distinct features such as hair, eyebrows, and nails. Additionally, the fetus starts to demonstrate movements, and its respiratory and digestive systems continue to mature.