Polyhydramnios is the presence of excessive amniotic fluid surrounding the unborn infant.
Amniotic fluid surrounds and cushions the infant throughout development. Decreased or excessive amounts of amniotic fluid may be associated with abnormalities in the fetus. Polyhydramnios may result from failure of the fetus to swallow and absorb amniotic fluid in normal amounts. This may occur as a result of gastrointestinal disorders, neurological problems, or a variety of other causes. Polyhydramnios may also be related to increased fluid production, as is the case with certain fetal lung disorders. Sometimes, no specific cause for polyhydramnios is found.
Impaired swallowing reflex, which leads to inability for amniotic fluid to be swallowed by fetus, leading to build up outside the fetus.
A condition which causes part of the brain not to form is called anencephaly.
polyhydrominos
In current obstetrical practice, polyhydramnios and oligohydramnios are usually detected during a routine prenatal ultrasound
As an isolated defect, anencephaly appears to be caused by a combination of genetic factors and environmental influences that predispose to faulty formation of the nervous system.
Ronald J. Lemire has written: 'Anencephaly' -- subject(s): Anencephalus, Anencephaly
the brain
Anencephaly.
n most cases, the exact cause cannot be identified. A single case of polyhydramnios may have one or more causes. Some cases are due to maternal diabetes mellitus, which causes fetal hyperglycemiaand resulting polyuria(fetal urine is a major source of amniotic fluid) and also rh-isoimmunisation can cause it. Few cases are associated with fetal anomalies that impair the ability of the fetus to swallow (the fetus normally swallows the amniotic fluid). These anomalies include:gastrointestinalabnormalities such as esophageal atresia, duodenal atresia, facial cleft, neck masses, tracheoesophageal fistula, and diaphragmatic hernias. An annular pancreas causing obstruction may also be the cause.Bochdalek's hernia, in which the pleuro-peritoneal membranes (especially the left) will fail to develop & seal the pericardio- peritoneal canals. This results in the stomach protrusion up into the thoracic cavity, and the fetus is unable to swallow sufficient amounts of amniotic fluid.fetal renaldisorders that results in increased urine production during pregnancy, such as in antenatal Bartter syndrome.[6]Molecular diagnosis is available for these conditions.[7]neurological abnormalities such as anencephaly, which impair the swallowing reflexchromosomal abnormalities such as Down's syndrome and Edwards syndrome (which is itself often associated with GI abnormalities)Skeletal dysplasia, or dwarfism. There is a possibility of the chest cavity not being large enough to house all of the baby's organs causing the trachea and esophagus to be restricted, not allowing the baby to swallow the appropriate amount of amniotic fluid.It can also be caused by intrauterine infection (TORCH)In a multiple gestation pregnancy, the cause of polyhydramnios usually is twin-twin transfusion syndrome.Other maternal causes include cardiac or kidneyproblems. Additionally, chorioangioma of the placenta can also cause this condition.A recent study distinguishes between mild and severe polyhydramnios and showed that Apgar score of less than 7, perinatal death and structural malformations only occurred in women with severe polyhydramnios.[8]In another study, all patients with polyhydramnios, that had a sonographically normal fetus, showed no chromosomal anomalies
It occurs during the first month of embryonic development
Anencephaly is a birth defect where the brain, skull and scalp do not develop fully or properly. It is a fatal defect. Anecephaly is the absence of a major part of the brain, skull or scalp during the embryonic development.
Anencephaly also known as neural tube defect.
Do you mean Encephalitis? Or Anencephaly? I'll explain them both, and you can just skip the one that you didn't mean. Encephalitis is acute inflammation of the brain. It can be caused by viral/bacterial infections, auto-immune disease, HSV, the later stages of Syphilis, Rabies, Parasitic/Protozoal infections, etc. There's a variety of different causes. Anencephaly is a very serious birth defect in which a baby is born without parts of the brain/skull. If you google images 'Anencephaly' be warned that the images ae very disturbing. It happens when the neural tube (The neural tube is responsible for forming the brain/skull amongst other things) closes up before the brain/skull is fully developed.