X-rays are known to have possible adverse effects on the development of the fetus, and the risks need to be weighed against the benefits.Congenital disorders are acquired before birth. Infants with certain congenital heart defects can survive only as long as the ductus remains open: in such cases the closure of the ductus can be delayed by the administration of prostaglandins to permit sufficient time for the surgical correction of the anomalies. Conversely, in cases of patent ductus arteriosus, where the ductus does not properly close, drugs that inhibit prostaglandin synthesis can be used to encourage its closure, so that surgery can be avoided. Other heart birth defects include ventricular septal defect,  pulmonary atresia, and tetralogy of Fallot. An abdominal pregnancy can result in the death of the fetus and where this is rarely not resolved it can lead to its formation into a lithopedion. Fetal pain
Fetal pain, its existence and its implications are debated politically and academically. According to the conclusions of a review published in 2005, "Evidence regarding the capacity for fetal pain is limited but indicates that fetal perception of pain is unlikely before the third trimester." However, developmental neurobiologists argue that the establishment of thalamocortical connections (at about 6+1⁄2 months) is an essential event with regard to fetal perception of pain. Nevertheless, the perception of pain involves sensory, emotional and cognitive factors and it is "impossible to know" when pain is experienced, even if it is known when thalamocortical connections are established.
Crossed dystopia (syn.unilateral fusion cross fused renal ectopia) is a rare form of renal ectopia where both kidneys are on the same side of the spine. In many cases, the two kidneys are fused together, yet retain their own vessels and ureters. The ureter of the lower kidney crosses the midline to enter the bladder on the contralateral side. Both renal pelves can lie one above each other medial to the renal parenchyma (unilateral long kidney) or the pelvis of the crossed kidney faces laterally (unilateral "S" shaped kidney). Urogram is diagnostic. The anomaly can be diagnosed through ultrasound or urography, but surgical intervention is only necessary if there are other complications, such as tumors or pyelonephritis. == References ==