Nishioka F Y
Department of Pharmacy, Lucile Salter Packard Children's Hospital, Stanford University Medical Center, Palo Alto, California 94304.
J Reprod Med. 1993 Jan;38(1 Suppl):83-8.
The use of locally applied prostaglandin E2 (PGE2) has become a common intervention in the management of the unripened cervix in term pregnancy. The extemporaneously prepared, vaginally administered prostaglandin E2 gels are most often used clinically in the United States. Large-scale clinical trials have not been conducted with these products. The extemporaneously prepared gels are not standardized with regard to potency, purity or stability; the assessment of efficacy and safety is based on anecdotal clinical reports. PGE2 and its metabolites are eliminated rapidly from the circulation, thus plasma levels are not useful in assessing clinical efficacy. Pharmacokinetic evaluations are based on plasma levels of the stable bicyclo-metabolite of PGE2. Plasma levels resulting from exogenous administration of PGE2 cannot be distinguished from plasma levels caused by endogenous production. Available evidence supports local application of low doses of PGE2 for cervical ripening prior to labor induction. Local application may minimize undesirable systemic effects and uterine hypertonus. A cost/benefit evaluation of a commercially prepared intracervical PGE2 gel must consider several factors in addition to acquisition cost including avoidance of other more costly procedures, such as cesarean section, instrumental delivery, anesthesia, transfusions and monitoring of prolonged labor and fetal outcome, liability issues and pharmacy preparation costs.
局部应用前列腺素E2（PGE2）已成为足月妊娠未成熟宫颈处理中的一种常用干预措施。在美国，临床最常使用的是临时配制、经阴道给药的前列腺素E2凝胶。尚未针对这些产品开展大规模临床试验。临时配制的凝胶在效力、纯度或稳定性方面未标准化；其疗效和安全性评估基于临床传闻报告。PGE2及其代谢产物可迅速从循环中清除，因此血浆水平对评估临床疗效并无用处。药代动力学评估基于PGE2稳定双环代谢产物的血浆水平。外源性给予PGE2所导致的血浆水平无法与内源性产生所致的血浆水平相区分。现有证据支持在引产之前局部应用低剂量PGE2促进宫颈成熟。局部应用可最大程度减少不良全身效应和子宫过度紧张。对市售宫颈内PGE2凝胶进行成本效益评估时，除购置成本外，还必须考虑多个因素，包括避免其他成本更高的操作，如剖宫产、器械助产、麻醉、输血以及对延长产程和胎儿结局的监测、责任问题和药房配制成本。
