Levetiracetam is classified as FDA pregnancy risk category C. In animal studies, there was evidence that levetiracetam produced developmental toxicity at doses similar to or greater than human therapeutic doses. There are no adequate and well-controlled studies in pregnant women. Levetiracetam should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. The effect of levetiracetam on labor and delivery in humans is not known. NOTE: Maternal clearance of levetiracetam is higher during pregnancy compared to baseline, especially during the third trimester (see Pharmacokinetics); if levetiracetam is continued during pregnancy, monitor seizure frequency closely. A dosage adjustment may be necessary for some patients. Physicians are advised to recommend that pregnant patients receiving levetiracetam enroll in the North American Antiepileptic Drug (NAAED) Pregnancy Registry to provide information about the effects of in utero exposure to the drug. Patients must call 1-888-233-2334 to enroll in the registry. The manufacturer of Keppra, UCB, has also established a pregnancy registry that patients or healthcare providers can enroll in by calling 1-888-537-7734.
Lewis Sarett of Merck & Co. was the first to synthesize cortisone, using a 36-step process that started with deoxycholic acid, which was extracted from ox bile .  The low efficiency of converting deoxycholic acid into cortisone led to a cost of US $200 per gram. Russell Marker , at Syntex , discovered a much cheaper and more convenient starting material, diosgenin from wild Mexican yams . His conversion of diosgenin into progesterone by a four-step process now known as Marker degradation was an important step in mass production of all steroidal hormones, including cortisone and chemicals used in hormonal contraception .  In 1952, . Peterson and . Murray of Upjohn developed a process that used Rhizopus mold to oxidize progesterone into a compound that was readily converted to cortisone.  The ability to cheaply synthesize large quantities of cortisone from the diosgenin in yams resulted in a rapid drop in price to US $6 per gram, falling to $ per gram by 1980. Percy Julian's research also aided progress in the field.  The exact nature of cortisone's anti-inflammatory action remained a mystery for years after, however, until the leukocyte adhesion cascade and the role of phospholipase A2 in the production of prostaglandins and leukotrienes was fully understood in the early 1980s.