Cashner K A, Christopher C R, Dysert G A
Department of Obstetrics and Gynecology, University of Cincinnati, Ohio.
Obstet Gynecol. 1987 Dec;70(6):827-30.
Chorionic villus sampling is being considered as an alternative to amniocentesis for genetic evaluation. The risk of subsequent spontaneous abortion from this invasive procedure, however, remains unclear. A prospective analysis of pregnancy outcome after ultrasound documentation of fetal viability at eight to 12 weeks' gestation was carried out in an uninstrumented population of patients to establish a background loss rate against which to evaluate the safety of chorionic villus sampling. All patients presenting to the authors' private practice from December 1983 to January 1986 were enrolled in the study. An ultrasound examination was performed at the first visit to confirm intrauterine pregnancy and assess gestational age; in gestations less than eight weeks, the sonogram was repeated four weeks later. Four hundred eighty-nine delivered patients are the subject of this study. We evaluated the differences between this group and those patients presenting either with a blighted ovum or beyond the first trimester, as well as the outcome of those patients with spotting early in gestation. This study suggests that if a live fetus is documented by ultrasonography at eight to 12 weeks' gestation, the risk of spontaneous abortion before 20 weeks' gestation in an uninstrumented population is 2.0%.
绒毛取样正在被视为羊膜穿刺术用于基因评估的一种替代方法。然而，这种侵入性操作导致后续自然流产的风险仍不明确。对一组未接受过相关操作的患者进行了一项前瞻性分析，这些患者在妊娠8至12周时经超声确认胎儿存活，以此确定一个背景流产率，用于评估绒毛取样的安全性。所有在1983年12月至1986年1月期间到作者私人诊所就诊的患者均纳入本研究。首次就诊时进行超声检查以确认宫内妊娠并评估孕周；孕周小于8周的患者，4周后复查超声。本研究以489例分娩患者为研究对象。我们评估了该组患者与那些出现空孕囊或妊娠中期之后就诊的患者之间的差异，以及妊娠早期有阴道点滴出血患者的结局。本研究表明，如果在妊娠8至12周时经超声确认胎儿存活，在未接受过相关操作的人群中，妊娠20周前自然流产的风险为2.0%。
