Oligohydramnios is one of the possible complications during pregnancy. The amniotic sac has too little amniotic fluid.


What is oligohydramnios?

Oligohydramnios occurs when the amniotic fluid in the amniotic sac decreases to less than 500 milliliters during pregnancy. This pregnancy complication occurs in around 0.5 to 4 percent of all pregnant women. In the last third of pregnancy, the trimester, there is an insufficient amount of amniotic fluid in 3 to 5 percent of all pregnancies. See acronymmonster for Definition of Copper Poisoning in English.

The production of amniotic fluid takes place from the 12th to 14th day of pregnancy. It is initially composed of water that comes from the mother. From the 20th week of pregnancy, the urine of the fetus then serves as the main component. Amniotic fluid is vital for the unborn child, as it is needed for the development of organs and provides protection against impact. For this reason, the pregnant woman should have the amount of her amniotic fluid checked at regular intervals.


The causes of oligohydramnios lie either with the mother or with the child. If the reduction in amniotic fluid is due to the baby, it is usually due to malformations of the kidneys or the urinary tract such as malformations of the urethra or the ureter. Potter’s syndrome is a frequently occurring malformation of the kidneys. The kidneys are no longer able to produce urine.

Sometimes, in Potter syndrome, no kidneys form at all. Likewise, polycystic kidneys and narrowing of the urethra or ureter can cause oligohydramnios. The malformations mean that the child cannot produce any urine or the urine cannot be excreted in the form of amniotic fluid in the amniotic sac. The loss of urine leads to a decrease in amniotic fluid. It is not uncommon for oligohydramnios to occur in monozygotic twin pregnancies and multiple pregnancies.

The reason for this is an imbalance in the blood exchange between the children. For example, one child gets too little blood, resulting in not enough amniotic fluid, while the other gets too much blood, resulting in too much amniotic fluid. One of the primary maternal causes of oligohydramnios is hypertension. This leads to damage to the placenta. This is then no longer able to fulfill its function.

In such cases, gynecologists speak of placental insufficiency. Another possible cause is premature rupture of membranes. This is accompanied by the loss of amniotic fluid. Another maternal cause of oligohydramnios can be dehydration in the mother, which also causes the child to receive less fluid and produce less urine.

Symptoms, Ailments & Signs

An oligohydramnios is often noticeable through reduced mobility of the unborn child. The mother feels her baby moving less often, which is due to the reduced amount of amniotic fluid. In addition, the belly of the pregnant woman hardly gets any bigger. Possible consequences of an oligohydramnios can be an intrauterine constraint, a heeled foot or a torticollis. There is also an increased risk of birth.

Diagnosis & course of disease

If the mother feels less movements of her child, it is advisable to consult the gynecologist. During the examination, he usually finds that the uterus is too small for the week of pregnancy. An ultrasound examination (sonography) can determine a reduction in amniotic fluid. It is important to rule out a ruptured membrane that happened a long time ago as the cause of the oligohydramnios.

If the complication occurs between the 14th and 26th week of pregnancy, the doctor uses a sonography to look for possible malformations in the child, as these can trigger the lack of amniotic fluid. The amniotic fluid index serves as a measure of the amount of amniotic fluid. A value between 8 and 18 centimeters is considered normal. If the value is lower, however, an oligohydramnios must be assumed. The course of an oligohydramnios depends on the extent of amniotic fluid loss. In most cases, the complications can be medically treated or even eliminated.


Oligohydramnios is usually a complication. This can have a very negative effect on pregnancy and the further development of the child. For this reason, early diagnosis and treatment of this disease is necessary to prevent further complications. The risk of a miscarriage increases enormously due to oligohydramnios, so that in the worst case the child can die during childbirth and endanger the life of the mother.

Likewise, the oligohydramnios can lead to the development of various malformations, so that those affected suffer from a heeled foot or a torticollis after birth. In most cases, oligohydramnios can be treated relatively well. There are no complications. If the complaint is diagnosed early enough, all malformations in the child can usually be avoided.

The birth itself usually takes place by caesarean section. This is especially the case when vaginal birth would be too risky for the life of the child. If the treatment and birth are successful, there will be no further complaints or complications, and the life expectancy of the child and the mother will not be reduced due to the illness.

When should you go to the doctor?

During pregnancy, women should always take part in all preventive and check-up examinations offered by a gynecologist so that the well-being of the offspring and the health of the mother-to-be can be checked. Changes and developments are documented. This means that action can be taken immediately in the event of discrepancies. In particular, women who have a multiple pregnancy should be particularly vigilant in the event of irregularities. If signs of an unusual change appear outside of the planned appointments for checking the developmental status of the fetus, an immediate visit to the doctor for clarification is advisable.

If the child moves very little or not at all in the womb, the observations should be discussed with a doctor. If the mother-to-be experiences anxiety or has a vague feeling that something might be wrong, a doctor’s consultation is necessary. If you feel unwell, have trouble sleeping or are feeling restless, you should consult a doctor. Sudden abnormalities or irregularities during pregnancy should be investigated as soon as possible. In the event of pain, bleeding or a sensory disturbance, the health status of mother and child should be clarified. Fluid excreted from the vagina during gestation is considered a warning signal from the organism. A doctor’s visit should take place

Treatment & Therapy

A special treatment of the oligohydramnios is not possible. Normally, the triggering causes can no longer be reversed. In the event that only a small amount of amniotic fluid is missing, it can often be sufficient to give the mother more fluids, such as water. If you lose large amounts of amniotic fluid, there are also treatment options. This includes the amniotic infusion, the filling of the amniotic sac with a solution of sugar and sodium chloride.

For this purpose, the doctor punctures the abdominal wall of the pregnant woman with a needle, which he carefully advances through a catheter to the child’s amniotic sac. He controls the course of the needle with the help of ultrasound. If the child has already developed far enough to be able to survive outside the mother’s body, preparations are made for an early birth. Depending on how far the pregnancy has progressed, an induction of lung maturation takes place.

In a normal vaginal birth, the lack of amniotic fluid usually causes changes in the child’s heartbeat. Due to the tighter space conditions, the baby squeezes its own umbilical cord. As a result, there is an interruption in the flow of blood between the placenta and the child. If vaginal birth is not possible or too risky, a caesarean section is performed.

Outlook & Forecast

Further health development depends on the severity of the disease. In some cases, the prognosis is extremely favorable. If a small amount of amniotic fluid is missing, it may be sufficient for the expectant mother to consume additional fluids. Water intake changes the amount of amniotic fluid available. There is a chance that spontaneous healing will occur and no further complications will arise.

If health discrepancies have already occurred in the unborn child, the prognosis worsens considerably. Acquired malformations can no longer be corrected with the current treatment methods. The individual severity of the existing complaints is decisive for the further development. Lifelong impairments can occur. Consequential disturbances due to health discrepancies are also possible. Doctors focus on symptomatic therapy.

Without medical attention, oligohydramnios can be fatal. With an unfavorable development, the survival of the fetus is at risk. At the same time, the expectant mother has an increased risk of suffering from long-term health problems. When the lack of amniotic fluid is detected, an immediate caesarean section is often considered. This depends on when the diagnosis was made and the developmental stage of the fetus. If the caesarean section proceeds without further complications, there are good prospects of safeguarding the lives of mother and child.


It is difficult to prevent oligohydramnios. However, since pregnant women who smoke are often affected, tobacco consumption during pregnancy is not recommended.


In most cases, those affected with oligohydramnios have only a few or limited direct follow-up measures available. For this reason, a doctor should be consulted at an early stage so that further complications or symptoms from this disease can be prevented. Self-healing cannot occur, so a doctor should be contacted at the first signs or symptoms.

Most patients with oligohydramnios require surgical intervention, which can permanently relieve the symptoms. Strict bed rest should be maintained thereafter, and exertion or physical and stressful activities should be avoided. After the birth of the child, it must be subjected to regular checks and examinations in order to identify and treat further damage to the body and internal organs at an early stage.

The support and care of one’s own family is often very important, which can also prevent the development of depression and other mental disorders. In rare cases, oligohydramnios reduces the life expectancy of both mother and child.

You can do that yourself

If oligohydramnios has been diagnosed, sufficient fluid intake is usually sufficient to compensate for the lack of amniotic fluid. In order to balance the excretion of minerals, care should be taken to ensure a balanced diet. The gynecologist can suggest an appropriate diet or refer the patient to a nutritionist.

In the case of oligohydramnios, the affected woman should be examined so that any developmental or genetic disorders in the child can be ruled out. In order to reduce the stress associated with this, various relaxation techniques from yoga or progressive muscle relaxation can be used, for example stretching exercises or autosuggestion in connection with physical exercises. Pregnant women who have been diagnosed with reduced amniotic fluid should always consult their gynaecologist. Often enough amniotic fluid forms by itself and no further measures are necessary.

In principle, the individual assessment of the doctor should be awaited before further measures are taken. If the oligohydramnios only occurs in the last stages of pregnancy, a specialist clinic should be consulted for further clarification so that the child is not endangered by the lack of amniotic fluid.