What are the common causes of oligohydramnios?
Jul 19, 2025
Source: Cainiu Health
Dr. Zhang Lu
Introduction
In general, oligohydramnios (low amniotic fluid) may be caused by factors such as advancing gestational age, insufficient water intake, premature rupture of membranes, placental insufficiency, or gestational hypertension. If related abnormalities occur, it is recommended to seek timely medical evaluation and treatment at a reputable hospital. In daily life, pregnant women should maintain a balanced diet and consume more water-rich vegetables and fruits.
Generally, oligohydramnios (low amniotic fluid) may be caused by factors such as advancing gestational age, insufficient water intake, premature rupture of membranes, placental insufficiency, and gestational hypertension. If abnormalities occur, it is recommended to seek timely treatment at a regular hospital. Detailed explanations are as follows:
1. Advancing Gestational Age
As pregnancy progresses into the late stages, the fetus gradually matures, and lung function develops fully. The fetal urine output may relatively decrease, while the amniotic membrane's secretory function also declines, leading to a gradual reduction in amniotic fluid. This is a normal physiological phenomenon that does not require special treatment, only regular prenatal checkups.
2. Insufficient Water Intake
If a pregnant woman consumes too little water daily, her body may enter a mildly dehydrated state, affecting blood circulation and subsequently reducing placental perfusion, resulting in insufficient fetal urine production and causing oligohydramnios. Pregnant women should ensure adequate daily water intake, generally recommended at 1500-2000 milliliters per day. They can also appropriately consume beverages such as soy milk and fruit juice to increase fluid intake.
3. Premature Rupture of Membranes
After premature rupture of membranes, amniotic fluid continuously leaks through the rupture, rapidly reducing amniotic fluid volume. Pregnant women should immediately rest in bed with the hips elevated to prevent further fluid loss. Additionally, maintain external genital hygiene, use sterile perineal pads, and prevent infection. If the gestational age is small and the fetus is viable, infection can be prevented under medical guidance with medications such as penicillin V potassium tablets, cefaclor capsules, and amoxicillin capsules.
4. Placental Insufficiency
The placenta is a vital organ for material exchange between the fetus and mother. When placental function declines, the fetus receives insufficient nutrients and oxygen, leading to redistribution of fetal circulation, reduced renal blood flow, and decreased fetal urine output, resulting in oligohydramnios. Under medical guidance, low molecular weight heparin sodium injection, compound amino acid injection, vitamin E soft capsules, and other medications can be used to improve placental blood circulation.
Gestational hypertension can affect systemic blood vessels, including placental vessels, leading to insufficient placental blood flow, fetal ischemia and hypoxia, and subsequently reduced fetal urine output, causing oligohydramnios. Patients should control blood pressure under medical guidance using medications such as labetalol tablets, nifedipine sustained-release tablets, and methyldopa tablets.
In daily life, pregnant women should maintain a balanced diet and consume more water-rich fruits and vegetables. Engage in moderate exercise such as walking to strengthen physical health. If significant amniotic fluid reduction occurs, seek medical attention promptly.
