At 24 weeks of fetal development, the baby measures about 11.5–13 inches from head to toe and weighs approximately 1.3–1.5 pounds. The body is becoming more filled out as fat begins to accumulate beneath the skin, though the skin remains thin and pink with visible blood vessels. The fetus now has a more recognizable newborn-like appearance. The lungs are reaching an important milestone at this stage. Air sacs continue to develop, and the cells begin producing surfactant, a substance that helps k