Crawford J S, Lewis M
Anaesthesia. 1986 Sep;41(9):900-5. doi: 10.1111/j.1365-2044.1986.tb12912.x.
An analysis of the outcome of 375 cases (383 fetuses) of cervical cerclage and 58 other operations (59 fetuses) conducted under general anaesthesia, which included the administration of nitrous oxide, failed to reveal a single instance of which nitrous oxide could have been clearly indicted as a cause of fetal abnormality The incidence of inevitable abortion and of low birth weight babies in the series of cervical cerclage conducted under general anaesthesia was identical to that in a series conducted under regional analgesia (115 fetuses). This represents the first of a two-part test of the proposition that nitrous oxide should not be administered to women in the first or second trimester. Our interim conclusion is that the proposition is unacceptable.
对375例（383例胎儿）宫颈环扎术以及58例（59例胎儿）在全身麻醉下进行的其他手术（包括使用氧化亚氮）的结果分析显示，未发现有任何一例能明确表明氧化亚氮是胎儿异常的原因。在全身麻醉下进行的宫颈环扎术系列中，难免流产和低体重儿的发生率与在区域镇痛下进行的系列手术（115例胎儿）相同。这是对氧化亚氮不应在孕早期或孕中期给予女性这一命题进行的两部分测试中的第一部分。我们的初步结论是该命题不可接受。
