Because the placenta is less elastic than the uterus, it tears away when the uterine tissue stretches suddenly. When anatomical risk factors are present, the placenta does not attach in a place that provides adequate support, and it may not develop appropriately or be separated as it grows. Cocaine use during the third trimester has a 10% chance of causing abruption. Though the exact mechanism is not known, cocaine and tobacco cause systemic vasoconstriction, which can severely restrict the placental blood supply (hypoperfusion and ischemia), or otherwise disrupt the vasculature of the placenta, causing tissue necrosis, bleeding, and therefore abruption.In most cases, placental disease and abnormalities of the spiral arteries develop throughout the pregnancy and lead to necrosis, inflammation, vascular problems, and ultimately, abruption. Because of this, most abruptions are caused by bleeding from the arterial supply, not the venous supply. Production of thrombin via massive bleeding causes the uterus to contract and leads to DIC.The accumulating blood pushes between the layers of the decidua, pushing the uterine wall and placenta apart. When the placenta is separated, it is unable to exchange waste, nutrients, and oxygen, a necessary function for the fetuss survival. The fetus dies when it no longer receives enough oxygen and nutrients to survive. Diagnosis
Placental abruption is suspected when a pregnant mother has sudden localized abdominal pain with or without bleeding. The fundus may be monitored because a rising fundus can indicate bleeding. An ultrasound may be used to rule out placenta praevia but is not diagnostic for abruption.
Cidofovir, brand name Vistide, is a topical or injectable antiviral medication primarily used as a treatment for cytomegalovirus (CMV) retinitis (an infection of the retina of the eye) in people with AIDS.Cidofovir was approved for medical use in 1996. Medical use
DNA virus
Its only indication that has received regulatory approval worldwide is cytomegalovirus retinitis. Cidofovir has also shown efficacy in the treatment of aciclovir-resistant HSV infections. Cidofovir has also been investigated as a treatment for progressive multifocal leukoencephalopathy with successful case reports of its use. Despite this,  the drug failed to demonstrate any efficacy in controlled studies. Cidofovir might have anti-smallpox efficacy and might be used on a limited basis in the event of a bioterror incident involving smallpox cases. Brincidofovir, a cidofovir derivative with much higher activity against smallpox that can be taken orally has been developed. It has inhibitory effects on varicella-zoster virus replication in vitro although no clinical trials have been done to date, likely due to the abundance of safer alternatives such as aciclovir. Cidofovir shows anti-BK virus activity in a subgroup of transplant recipients. Cidofovir is being investigated as a complementary intralesional therapy against papillomatosis caused by HPV.It first received FDA approval on 26 June 1996, TGA approval on 30 April 1998 and EMA approval on 23 April 1997.It has been used topically to treat warts. Other
It has been suggested as an antitumour agent, due to its suppression of FGF2. Administration
Cidofovir is only available as an intravenous formulation.