[Abstract] On the maternal and child forum, an expectant father, Mr. He, sent a request for help: My wife is 8 months pregnant. The doctor said that my wife has low amniotic fluid. In fact, the problem is not serious. What is the cause of oligohydramnios? Is it really good to have low amniotic fluid? What can I do as a husband to help my wife?
Amniotic fluid refers to the fluid in the amniotic cavity and is the water that nourishes the fetus. The common name is cytoplasmic water. During pregnancy, the amniotic membrane forms a fluid-filled sac that surrounds the embryo (fetus). The fluid in the middle is amniotic fluid. It is an important component in maintaining fetal life throughout pregnancy. At different stages of fetal development, the sources of amniotic fluid are also different. In early pregnancy, amniotic fluid mainly comes from the plasma component of the embryo; later, as the embryo\’s organs begin to mature and develop, other things, such as the fetal urine, respiratory system, gastrointestinal tract, umbilical cord, placental surface, etc., also become amniotic fluid. source.
Composition of amniotic fluid: 98% amniotic fluid is water, containing a small amount of inorganic salts, organic hormones and shed fetal cells. The amount of amniotic fluid generally increases with the number of weeks of pregnancy. At 20 weeks, the average is 500 ml; it will increase to 700 ml around 28 weeks; it will be the most at 3236 weeks, about 10001500ml; and then gradually decrease. Therefore, clinically, 300-2000 ml is the normal range. The doctor said that Teacher He\’s wife had oligohydramnios, which means that the amniotic fluid did not meet the above indicators. There are many causes of oligohydramnios. Generally speaking, there are the following causes:
Reasons for low amniotic fluid in pregnant women 1: Insufficient drinking water, insufficient blood volume, drug effects, pregnancy-induced hypertension, etc.
Reason 2 for low amniotic fluid in pregnant women: placental insufficiency.
Placental insufficiency leads to intrauterine hypoxia, reduced blood supply to the pulmonary capillary bed, reduced amniotic fluid exchange, reduced renal blood flow, reduced fetal urine output, chromosomal abnormalities, congenital anomalies, growth retardation, stillbirth, postterm pregnancy, etc.
Reason 3 for pregnant women with low amniotic fluid: intrauterine growth retardation (IUGR).
Oligohydramnios is one of the hallmarks of intrauterine growth retardation. Chronic hypoxia leads to a redistribution of fetal blood circulation, mainly supplying the brain and heart, while renal blood flow is reduced and fetal urine production is reduced, resulting in oligohydramnios.