Placental maturity level 2 at 24 weeks is normal. The placenta is between the fetus and the mother, and is an important organ for maintaining normal fetal development, with material exchange, defense function, synthesis and immune function.Ultrasound classifies placental maturity in pregnancy into four grades: 0, 1, 2 and 3. On mid-pregnancy ultrasound, a cut at the placental chorionic plate is observed, which extends to the placental parenchyma but does not reach the basal layer, and the placental parenchyma particles become coarser, with the appearance of stronger short columnar echoes, suggesting a grade 2 placenta, i.e., the placenta has matured, which is generally normal. If the mid-pregnancy placental maturity is more than grade 2, i.e., grade 3 placenta, marking that the placenta has matured and tends to aging, it is not normal at this time. The aging of the placenta will reduce the amount of nutrients it can transport, which will affect the development of the fetus if it cannot continue to tolerate it in the uterus.