The amount of amniotic water is greatly related to the health of the fetus.
The uterine abdominal circumference of the mother will increase, and vice versa, but there are too many influencing factors, and generally we use ultrasound to estimate the amount of amniotic fluid.
There are two reporting methods for amniotic fluid during ultrasonography, one is the maximum depth of amniotic fluid, and the deepest meridian of the amniotic pool under ultrasound images is determined, which is generally used when the gestational age is small; One is the amniotic fluid index, which divides the uterus into four quadrants, up, down, left and right, and the sum of the values of the deepest meridians in the four quadrants is the amniotic fluid index.
The amniotic fluid index in the third trimester is less than 5, indicating that the amniotic fluid is too little, possibly less than 300ml, and if the amniotic fluid index exceeds 18, then it means that the amniotic fluid is too much, which may exceed 2000ml.
Too little amniotic fluid
The main component of amniotic fluid in the third trimester of pregnancy is the urine of the fetus. The main reason for the lack of amniotic fluid is the poor function of the placenta, the mother can not provide enough nutrition and water to the fetus, then the fetus's urine will not be more, as if we do not drink water, less urine is a truth.
Placental dysfunction is not only manifested by less amniotic fluid, but also with less fetal development than normal fetuses. Fetal growth restriction and oligohydramnios may be causal.
The second cause of oligohydramnios is malformations of the urinary system of the fetus, including dysplasia of the kidneys. The kidneys are the organs that produce urine, and if the kidneys cannot produce urine, there will be less natural amniotic fluid.
However, it will manifest as persistent amniotic fluid from the second trimester onwards, and if there is suddenly too little amniotic fluid in the third trimester, it may indicate placental dysfunction and fetal hypoxia.
In addition to suggesting abnormalities in fetal development, too little amniotic fluid also has an impact on lung development. The fetus begins with a breathing movement, and the lungs are filled with amniotic fluid.
If there is too little amniotic fluid at the beginning of the second trimester, it often leads to the fetus's lung dysplasia and insufficient lung volume. Fetal lung dysplasia will occur after birth, and respiratory distress syndrome will occur, resulting in severe neonatal death.
There is little amniotic fluid in the third trimester, and there is no pressure buffer between the uterus and the carcass and the umbilical cord, which will cause the umbilical cord to be compressed and affect the nutrition and oxygen supply of the fetus.
What should I do if I have too little amniotic fluid?
1. Strengthen guardianship
If fetal malformations are not found, fetal movements, fetal heart rate, and ultrasound are closely monitored. Some cases can be alleviated by drinking water and amniotic fluid after infusion.
2. Replenish amniotic fluid
Injection of liquid directly into the amniotic cavity is only suitable for the earlier occurrence of too little amniotic fluid. However, there are not many people who may cause infection, etc., and there are not many people who have reduced amniotic fluid in the second trimester, so they are less clinically used.
3. Termination of pregnancy
If the fetus is close to term, the fetal lungs are mature, the amniotic fluid continues to decrease, and the mother's disease cannot be improved, then letting the baby leave the harsh environment in the uterus as soon as possible is more conducive to the baby's growth.
hydramnios
Hyperhydramnios usually occurs in the third trimester, mainly in the fetus with a lot of urine.
One reason is that the fetus is overnutrition, such as: the fetus is too large, the mother has mild diabetes, can lead to excessive amniotic fluid.
Fetal malformations can also lead to excessive amniotic fluid, mainly malformations of the digestive tract such as esophageal atresia, so that amniotic fluid can not be reduced normally through the digestive tract.
Open neural tube defects, abdominal wall defects can lead to cerebrospinal fluid outflow, excessive exudation of body fluids leading to excessive fetal amniotic fluid.
Some chromosomal abnormalities can lead to impaired swallowing function, intrauterine viral infections, fetal edema due to fetal hemolysis, and can also lead to hyperhydramnios.
In addition to being a signal of fetal health, too much amniotic fluid can also affect the health of the mother and fetus.
Excessive amniotic fluid leads to excessive swelling of the uterus, prone to premature rupture of membranes, placental abruption, postpartum uterine contractions, postpartum bleeding and other complications, acute amniotic fluid is too much, but also affects the mother's blood circulation system, resulting in mother chest tightness, shortness of breath, inability to lie flat, edema aggravation and so on.
The amount of amniotic fluid is very important, so doctors attach great importance to the amount of amniotic fluid checked by ultrasound in the second and third trimesters.