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What is Polyhydramnios is NOT seen with and explain in detail?
(A) Renal agenesis # POLYHYDRAMNIOS: The underlying cause of the excessive amniotic fluid volume is obvious in some clinical conditions and is not completely understood in others.> Causes include the following: Multiple pregnancy: Twin gestation with twin-to-twin transfusion syndrome (increased amniotic fluid in the recipient twin and decreased amniotic fluid in the donor) or multiple gestations> Fetal anomalies, including esophageal atresia (usually associated with a tracheoesophageal fistula), tracheal agenesis, duodenal atresia, and other intestinal atresias CNS abnormalities Anencephaly; Open spina bifida; and neuromuscular diseases that cause swallowing dysfunction; Congenital cardiac-rhythm anomalies associated with hydrops, fetal-to-maternal hemorrhage, and parvovirus infection; Facial clefts & neck masses; Hydrops fetalis> Chromosomal abnormalities, most commonly trisomy 21, followed by trisomy 18 and trisomy 13.> Fetal akinesia syndrome with absence of swallowing> Placental: Chorioangioma of the placenta> Maternal: Poorly controlled maternal diabetes mellitus (Oligohydramnios may also be seen if severe vascular disease is present.) & cardiac or renal disease> Oligohydramnios:> Fetal urinary tract anomalies, such as renal agenesis, polycystic kidneys, or any urinary obstructive lesion (E.g., posterior urethral valves)> PROM and chronic leakage of the amniotic fluid> Chorioamnionitis is an additional important maternal complication from oligohydramnios due to rupture of the membranes, which has an incidence of 21-74%.> The earlier chorioamnionitis occurs in pregnancy, the greater the fetal risk of bronchopulmonary dysplasia (BPD), neurologic complications, pulmonary hypoplasia, and, in severe cases, respiratory failure in the neonate.> Placental insufficiency, as seen in pregnancy-induced hypertension (PIH), maternal diabetes, or postmaturity syndro ne when the pregnancy extends beyond 42 weeks' gestation> Maternal use of prostaglandin synthase inhibitors or ACE inhibitorsHYDRAMNIOSOligo hydramnios (< 100 ml AF)Polyhydramnios (> 2000 ml AF)Potter syndrome (renal agenesis)Obstruction to GIT (E.e. Esophageal atresia) 100%Urinary tract obstructionAnencephaly (in 50%)Placental insufficiency with IUGROpen spina bifidaBreechMaternal DM