How mature should the placenta be?

Whether the placenta is mature or not has a great relationship with whether the fetus reaches the due date. The nutrients in the placenta are for the fetus. The maturity of the placenta means that our fetus has absorbed enough nutrients and is ready to be born. What we need to make clear is that it doesn’t necessarily take ten months of pregnancy for the baby to be born. As long as the placenta is mature, the baby can be born early. There are four levels of placental maturity. So at which level should the placenta be mature before birth?

How mature is the placenta? How mature is the placenta?

Placental maturity is a measure of whether the fetus is developing normally. There are four levels of placental maturity: grade O, grade 1, grade 2, and grade 3. Level 1 indicates that the placenta is basically mature; Level 2 indicates that the placenta is mature; Level 3 indicates that the placenta is aged. Due to calcification and cellulose deposition, the placenta's ability to distribute oxygen and nutrients is reduced, and the fetus is in danger. Everyone's situation is different. Placenta: mid-pregnancy (12-28 weeks) - placenta grade 0; late pregnancy (30-32 weeks) - placenta I; after 36 weeks - placenta grade II (relatively mature). If a grade III placenta is found before 37 weeks and combined with the value of the biparietal diameter and the estimated fetal weight of 2500 grams, placental precocity should be considered and the patient should be alert to the possibility of intrauterine growth retardation. At 38 weeks, the placenta enters grade III, marking placental maturity. You can give birth when the placenta reaches grade 2 maturity.

Normal value :

1. Grade 0: The villous plate of the placenta appears as a bright straight line, and the substance is uniform and fine granular, with no visible base. It usually appears before 28 weeks of pregnancy.

2. Grade I placenta: The villous plate is a slightly undulating bright line, the placental parenchyma is slightly coarse, the echo is slightly stronger, and the basal layer has not yet appeared. It usually occurs at gestational weeks 29-36.

3. Grade II placenta has notches on the chorionic villus plate that extend to the placental parenchyma but do not reach the basal layer. The placental parenchyma granules become coarser, with stronger short columnar echoes. Irregular and stronger strip echoes may appear in the basal layer, parallel to the muscle wall. The gestational age is usually between 36 and 40 weeks.

4. Grade III: The villous notch of the placenta has reached the basal layer, and multiple strong echo rings appear in the placental substance. Small echo-free pools may appear inside, and sometimes calcification foci with enhanced reflection can be seen.

5. Level 0 to I at 28 weeks, level I to II at 36 weeks, level II to III at 40 weeks.

Function of the placenta

1. Gas Exchange

The most important substance to maintain fetal life is O2. The placenta is between the mother and the fetus. O2 and CO2 are exchanged by simple diffusion, which can replace the function of the fetal respiratory system.

2. Nutrient supply can replace the function of the fetal digestive system

(1) Glucose is the main source of heat energy for the fetus and crosses the placenta by facilitated diffusion; (2) The concentration of amino acids in fetal blood is higher than that in maternal blood and crosses the placenta by active transport. Most electrolytes and vitamins pass through the placenta by active transport; (3) The placenta contains a variety of enzymes, such as oxidases, reductases, hydrolases, etc., which can break down complex compounds into simple substances, and can also synthesize simple substances and supply them to the fetus.

3. Eliminate fetal metabolic products, such as urea, uric acid, creatinine, creatine, etc., which are sent into the maternal blood through the placenta and excreted from the mother's body, thus replacing the function of the fetal urinary system.