Oligoamnios/anamnios: what causes and consequences of the lack of amniotic fluid?

Oligoamniosanamnios what causes and consequences of the lack of amniotic

Amniotic fluid is essential for the survival of the baby in utero. When the mother-to-be lacks it, the consequences can be fatal. What are the risks for the baby? What are the treatments ? The point with Dr Caroline Verhaeghe, obstetrician gynecologist.

amniotic fluid is the biological fluid in which the fetus evolves throughout pregnancy. Essentially composed of urine and pulmonary secretions, it essentially aims to protect the fetus and promote its development. He swallows it, then eliminates it by urinating. But it can happen that the pregnant woman does not have enough amniotic fluid.

What are oligoamnios and anamnios?

The volume of amniotic fluid varies throughout pregnancy. At first, it represents only a few milliliters to reach up to 1000 ml at the 34th week of amenorrhea (SA) before decreasing and falling to 800 ml at term. “The terms oligoamnios and anamnios refer to an insufficient amount of amniotic fluid. When there are not enough, we speak of oligomanias and when there are none left at all, we speak of anamnios“, says Dr. Caroline Verhaeghe.

“When there is not enough amniotic fluid, we speak of oligomanias and when there is no more at all, we speak of anamnios”.

When do we speak of moderate oligohydramnios?

If in doubt, the obstetrician can assess the amount of amniotic fluid by measuring the large cistern of amniotic fluid. We speak of moderate oligohydramnios when the height is less than 30mm.

When do we speak of severe oligohydramnios?

Severe oligohydramnios is defined by a height of less than 20mm.

Why is there no amniotic fluid?

The highlighting of a oligoamnios or anamnios must systematically search for ae premature rupture of membranes. “This is the most common cause of amniotic fluid deficiency, and the diagnosis is quite easily made with a test or even sometimes with a clinical examination alone., comments the obstetrician-gynecologist. Other possible causes can be:

  • A renal or urinary anatomical anomaly;
  • High blood pressure;
  • Growth retardation (IUGR);
  • Maternal-fetal infection;
  • A passing of the term.

What are the consequences of a lack of amniotic fluid?

  • Iamniotic fluid protects the baby against infections. Premature rupture of the membranes therefore exposes you to a significant risk of infection.
  • It also increases the risk of delivery within 48 hours.
  • Amniotic fluid also allows the baby to develop his lungs and to breathe in utero. Therefore, an insufficient amount of amniotic fluid can lead to pulmonary aplasia, that is, insufficient lung development.
  • Amniotic fluid gives the baby space. An oligoamnios or anamnios impedes fetal movement, which could lead to malposition of the limbs or arthrogrtyposis (the limbs are all folded up so that at birth the baby is unable to extend its legs). limbs and to move).
  • An insufficient amount of amniotic fluid can also lead to fetal death in utero.

What to do in case of lack of amniotic fluid?

The treatment is adapted according to the stage of the pregnancy and the cause at the origin of the oligoamnios or the anamnios. First, rest is recommended. “In the event of a chromosomal abnormality or malformation detected early, a medical termination of pregnancy can be mentioned. If rupture of membranes occurs at an advanced stage of pregnancy permitting, labor can be induced“, informs our interlocutor.

Thanks to Dr Caroline Verhaeghe, obstetrician gynecologist

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