Ursolic acid (UA) is a pentacyclic triterpenoid and has the characteristics to serve as a potential therapeutic agent for a range of disorders. However, detailed studies of the toxicity of UA, especially developmental toxicity of UA, are non-existing. The objective of this study was to determine the potential effects of UA on fetal development, adult reproductive system, and major organs. UA was dissolved in a 0.5% hydroxypropyl methylcellulose, 0.1% Tween 80 in Milli-Q Water solution. A 100, 300 or 1000 mg/kg/day dose of UA or a control vehicle was administered orally for 15 days to adults (Han Wistar) and pregnant females (Sprague-Dawley). The administration of UA in adults did not cause deaths or resulted in abnormal (reproductive) organ or body weights at the dose up to 1000 mg/kg/day. The administration of UA resulted in no significant toxicological changes in either maternal nor fetal subjects in terms of body weight, organ weights, food consumption, gross pathology, sex organs, maternal performances, and fetal performances. Together, this study indicates that oral dosing with UA is safe for adult rats and their offspring and the no observed adverse effect level for UA is likely higher than 1000 mg/kg/day.

熊果酸（UA）是一种五环三萜类化合物，具有可作为一系列疾病的潜在治疗剂的特征。然而，关于UA的毒性，特别是UA的发育毒性的详细研究尚不存在。这项研究的目的是确定UA对胎儿发育，成人生殖系统和主要器官的潜在影响。将UA溶于Milli-Q水溶液中的0.5％羟丙基甲基纤维素，0.1％Tween 80中。对成年人（Han Wistar）和怀孕的女性（Sprague-Dawley）口服给予100、300或1000 mg / kg / day剂量的UA或对照载体15天。在成人中服用UA不会导致死亡或导致高达1000 mg / kg /天的剂量的异常（生殖）器官或体重。在体重，器官重量，食物消耗，总体病理学，性器官，产妇表现和胎儿表现方面，UA的使用对孕妇和胎儿受试者均无明显的毒理学改变。总之，这项研究表明，口服UA对成年大鼠及其后代是安全的，未观察到的UA不良反应水平可能高于1000 mg / kg /天。