Oligohydramnios sequence

The Oligohydramnios sequence describes the effects of insufficient amniotic fluid production. These are severe malformations that develop during embryogenesis due to small amounts of amniotic fluid. The disease is fatal.

What is an oligohydramnios sequence?

The Potter syndrome or the oligohydramnios sequence can already be diagnosed prenatally as part of a prenatal ultrasound examination. From the 17th week of pregnancy, a Potter syndrome can be clearly seen.
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The Oligohydramnios sequence describes the effects of insufficient amniotic fluid production during pregnancy. The embryo cannot develop normally due to the limited space due to the small amount of amniotic fluid. Serious malformations of the internal and external organs occur. First, the syndrome was described by the American pathologist Edith Potter with bilateral absence of the kidneys (bilateral renal agenesis). Hence it is also called Potter Syndrome designated.

Potter performed around 5000 autopsies on 3 female and 17 male embryos or newborns. Since the malformations are not limited to the absence of the kidneys, the term oligohydramnios sequence is used. The lack of amniotic fluid during pregnancy is also known as oligohydramnios. By definition, this is the case when the amount of amniotic fluid falls below 200 to 500 ml.

The amniotic fluid index is less than 5.1 cm or the amniotic fluid deposits are less than 2 cm between the placenta (placenta), uterine wall and fetus. Oligohydramnia occurs in up to four percent of pregnancies and can have several causes. Only rarely does an oligohydramnios sequence develop from this.

causes

The cause of an oligohydramnios sequence is the lack of amniotic fluid. The most common cause of premature rupture of the bladder is the loss of amniotic fluid. However, this is not the cause of an oligohydramnios sequence because the amniotic fluid loss occurs shortly before birth. The oligohydramnios sequence can only develop in the presence of long-term oligohydramnios. This is mainly caused by decreased urine production by the embryo.

Furthermore, severe growth retardation of the baby can lead to this. Functional disorders of the placenta due to high blood pressure or nicotine consumption also sometimes cause oligohydramnios. Other reasons could be obstructive urinary tract disease or chromosomal aberrations. As a result of the insufficient amount of amniotic fluid, there is a lack of space for the embryo, since it can only develop within the amniotic fluid.

These restricted space conditions lead to unusual growth conditions for the fetus. All malformations are due to it. However, in some cases, existing malformations of the kidneys or the urinary tract may restrict urine production and urine excretion. This results in decreased amniotic fluid production, which in turn hinders the development of the rest of the organs.

Overall, it is therefore not entirely clear whether the clinical picture of the oligohydramnios sequence can also be genetically determined or is really only based on growth disorders due to the oligohydramnios. There may also be multiple causes.

Symptoms, ailments & signs

The oligohydramnios sequence is characterized by severe internal and external dysplasia. The most important symptom is the malformation of the genitourinary tract. The two kidneys are particularly affected. They are either completely absent (renal agenesis) or they are severely underdeveloped. In addition, there is hypoplasia (underactive) of the lungs. In addition to club feet, other malformations of the extremities or the spine can occur.

The malformations on the face, known as Potter faces, are particularly noticeable. These dysmorphisms are similar to Down syndrome. The auricles are specially shaped for low-set and flat ears. The cartilage substance of the auricles is missing. Another symptom is a medial epicanthus. This is a double crease similar to the Mongolian crease on the inner edge of the eye.

In addition, the eye relief is comparatively large, which is referred to as hypertelorism. After all, the lower jaw is underdeveloped. It therefore appears shortened. The prognosis for the disease is very poor. Because of the renal agenesis alone, death occurs either before the child is born or shortly afterwards.

Diagnosis & course of disease

The Potter syndrome or the oligohydramnios sequence can already be diagnosed prenatally as part of a prenatal ultrasound examination. From the 17th week of pregnancy, a Potter syndrome can be clearly seen. It can be determined by the significant growth retardation and the unusual forced posture due to the lack of space due to the lack of amniotic fluid.

Complications

Due to the oligohydramnios sequence, the children suffer from very severe malformations and malformations. In serious cases, the children can be born dead or die shortly after birth. As a rule, the parents and relatives of the child also suffer from severe psychological complaints and also from depression.

Furthermore, the kidneys can be completely absent in the patient, so that the child is directly dependent on dialysis. Down syndrome can also occur and significantly reduce the quality of life of the person affected. The lower jaw is shortened and there are also hearing problems and visual impairment. In most cases, however, the child dies shortly after birth as a result of the oligohydramnios sequence.

Treatment of the oligohydramnios sequence after birth is unfortunately not possible. However, the complaint can be diagnosed relatively early, so that early treatment of this disease is possible. The deficits of the amniotic fluid can be compensated so that the malformations can be avoided. The oligohydramnios sequence does not pose a health risk to the mother and there is no reduction in life expectancy.

When should you go to the doctor?

The far-reaching consequences of a lack of amniotic fluid are dramatic for the developing child. There are numerous deformities, as a result of which the child dies. The possible causes of an oligohydramnios sequence have not been clarified; multicausal causes are obvious.

It is true that an oligohydramnios sequence can be diagnosed prenatally and as part of a routine ultrasound examination. However, the presence of an oligohydramnios sequence can only be recognized after the 17th week of pregnancy. But then it is too late to terminate the pregnancy. However, if the gynecologist detects the amniotic fluid deficiency in good time, it can be compensated for. In this case, the child is likely to be born healthy or with only minor consequential damage.

If there is a pronounced oligohydramnios sequence, the unborn child often dies before birth. Sometimes it doesn't die until shortly afterwards. Due to the lack of space in the amniotic sac, the affected child was so severely damaged that it would not be able to survive even with the best medical help. In some cases the children are born alive but with severe kidney damage. You are immediately on dialysis. Such children learn that visits to the doctor are part of their short life.

Therapy & Treatment

Unfortunately, therapy is no longer possible if there is a pronounced oligohydramnios sequence. The prognosis is 100 percent fatal. If the baby is not born dead, it will die within a short time due to kidney and lung malformations. However, the triggering cause of the oligohydramnios sequence (oligohydramnios) can be treated during pregnancy. As already mentioned, oligohydramnios is characterized by a reduced amount of amniotic fluid.

Evidence of this can be found in an unusually small uterus and reduced child movement. That already indicates cramped space conditions. Sometimes it is enough for the pregnant woman to drink enough to bring the amount of amniotic fluid back to normal. This is the case when only temporary causes have led to a reduction in amniotic fluid. However, if the amount of amniotic fluid cannot be balanced by drinking, the child can expect undesirable developments.

In this case there is also the option of compensating for the amount of amniotic fluid through an amniotic infusion. An amniotic infusion is an amniotic fluid replenishment from the outside. With the help of a catheter or a needle, the amniotic fluid space is filled with a glucose-saline solution. This measure takes place under ultrasound control. However, if the child is in a poor general condition, the method of choice is to deliver the child prematurely. However, induction of lung maturation should be initiated beforehand.

Outlook & forecast

If insufficient amniotic fluid is produced during pregnancy, it can be a death sentence for the embryo. Too little amniotic fluid means that the unborn child cannot develop properly. It would suffer from severe malformations due to the oligohydramnios sequence or die in childbirth.

Obviously the oligohydramnios sequence arises multifactorial. Most children with the resulting deformities and consequential damage die at birth or a short time later. Those who survive longer are severely damaged and deformed in many organ systems and limbs. Among other things, the kidneys are missing. That alone prevents many of the children from surviving. The survivors are dependent on dialysis.They also have the most severe deformities.

Nowadays, however, prenatal examinations can determine whether or not there is enough amniotic fluid. If a deficiency is found, the amount of amniotic fluid can be increased. In this way, the serious consequential damage caused by the oligohydramnios sequence can be avoided. However, it is problematic that this examination only makes sense after the 17th week of pregnancy because the doctors cannot determine the lack of amniotic fluid beforehand. By then it will be too late for an abortion.

However, if the lack of amniotic fluid is recognized at this point in time, most children can be born healthy and with a good prognosis. Some show slight deformities.

prevention

To prevent an oligohydramnios sequence, a sufficient amount of amniotic fluid must be ensured during pregnancy. If there are signs of oligohydramnios, appropriate measures to replenish the amniotic fluid should be taken immediately.

You can do that yourself

Since the oligohydramnios sequence is a fatal disease, there are very few self-help measures. To prevent an oligohydramnios sequence, a sufficiently high amount of amniotic fluid must always be ensured during pregnancy. Sometimes it is enough for the pregnant woman to compensate for increased fluid loss through drinking.

If an oligohydramnios sequence is already diagnosed, the life expectancy of the unborn child is already very low due to possible lung and kidney damage. Since this represents an exceptional psychological situation for parents and relatives, it is important to offer sufficient support. As a person affected, it can help to open up to such support offers, which are often offered by hospitals and psychological services. Your own social environment should not be neglected in such a situation. An intact social environment can help to deal with the stress of an oligohydramnios sequence and its consequences.

The first signs of depression should be taken seriously and responded to. Alternative therapies and relaxation methods such as yoga and meditation can help you to gain new courage to face life even during the difficult time of illness in your own child or that of a loved one.