amniotic fluid
Quick Summary
Amniotic fluid is a protective liquid contained within the amnion, a membrane that forms the amniotic sac. This sac encloses the embryo in reptiles, birds, and mammals, providing a cushion against mechanical injury and preventing dehydration and tissue adhesion.1
In humans, the amniotic fluid typically totals about 1,000 ml (slightly over a quart) during pregnancy. Excessive fluid, known as hydramnios or polyhydramnios, can occur with fetal abnormalities, multiple fetuses, or maternal conditions like diabetes. Conversely, a deficiency in amniotic fluid, called oligohydramnios, is rare and can lead to fetal distortion and deformities if it occurs early in pregnancy. The exact cause of abnormal amniotic fluid levels is often unknown, but theories suggest imbalances in fluid transfer between the fetus and mother.23
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- pregnancyAbnormalities of the amniotic fluid
Hydramnios, sometimes called polyhydramnios, is the presence of an excessive amount of amniotic fluid. Normally the uterus contains approximately 1,000 millilitres (slightly more than one quart) of amniotic fluid; anything over 2,000 millilitres is abnormal. Accumulations of more than 3,000 millilitres occur…
Read MoreHydramnios, sometimes called polyhydramnios, is the presence of an excessive amount of amniotic fluid. Normally the uterus contains approximately 1,000 millilitres (slightly more than one quart) of amniotic fluid; anything over 2,000 millilitres is abnormal. Accumulations of more than 3,000 millilitres occur…
Read More - congenital disorderDeformities
…these involve a lack of amniotic fluid (oligohydramnios) buffering the fetus from the pressure of the uterine wall and may be due to leakage or failure to produce fluid. Characteristics include flattening of the nose and ears, fixation of the joints (leading to clubbed hands and feet), growth retardation, and…
Read More…these involve a lack of amniotic fluid (oligohydramnios) buffering the fetus from the pressure of the uterine wall and may be due to leakage or failure to produce fluid. Characteristics include flattening of the nose and ears, fixation of the joints (leading to clubbed hands and feet), growth retardation, and…
Read More - Down syndromeIncidence and diagnosis
…cells are taken from the amniotic fluid or from the mother’s placenta and analyzed for the presence of the abnormal chromosome. Because these procedures are invasive, however, they are associated with an increased risk of miscarriage.
Read More…cells are taken from the amniotic fluid or from the mother’s placenta and analyzed for the presence of the abnormal chromosome. Because these procedures are invasive, however, they are associated with an increased risk of miscarriage.
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