If the amniotic fluid at 30 weeks of pregnancy is not very serious, the amount of amniotic fluid can be increased by drinking a lot of water and rehydration. If it is caused by diseases, such as gestational hypertension, aging of the placenta, malformation of the urinary system or chromosomal abnormality, it is necessary to take medication or induction of labor according to the different situations. 1. Non-pathological causes: If the pregnant woman has no pathological conditions and the decrease in amniotic fluid is not very large, she can increase the amount of amniotic fluid by drinking a lot of water and replenishing fluids. 2. Gestational hypertension: Hypertension during pregnancy may lead to a decline in placental function, which may cause low amniotic fluid. Clinically, oral antihypertensive drugs are often used to reduce blood pressure, and after the blood pressure is reduced to normal, regular ultrasound is used to check the change of amniotic fluid volume. 3. Placenta aging: under normal circumstances, the maturity of the placenta is normal in the 30th week of pregnancy, if the placenta is aging at this time, there will be less amniotic fluid, and low molecular heparin treatment can be carried out under the guidance of the doctor, to improve the circulation of the placenta and increase the amount of amniotic fluid. 4. Fetal urinary malformation: amniotic fluid is mainly composed of fetal urine, if there is a serious malformation of the urinary system, can lead to amniotic fluid, according to the wishes of the pregnant woman to decide whether to induce labor. 5. Chromosomal abnormality: low amniotic fluid may also be caused by chromosomal abnormality, you can do umbilical cord blood puncture, pay attention to whether the fetal chromosomes are normal. If the fetus is found to have serious chromosomal abnormalities, it is necessary to induce labor to give up the fetus. The occurrence of low amniotic fluid will affect the growth and development of the fetus, so pregnant women need to find out the cause as soon as possible and deal with it, and not to use medication privately, so as not to cause adverse consequences.