Green J R, Soohoo S L
Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California, San Francisco.
Obstet Gynecol. 1989 May;73(5 Pt 1):732-8.
Rectal injury during childbirth is a complication with potentially debilitating long-term consequences. Several factors have been suggested as influencing the risk of rectal injury. Among these are parity, infant birth weight, and various procedures performed by the birth attendant, including episiotomy. Whether episiotomies protect against or provoke laceration of the rectal sphincter and rectal mucosa is particularly controversial. Logistic analysis was used in an observational study of 2706 spontaneous cephalic deliveries to determine the risk of rectal injury for each of six explanatory factors, simultaneously controlling for the other factors. The adjusted risk for rectal injury was significantly increased for midline episiotomy (8.9 versus no episiotomy), nulliparity (3.3 versus parous), delivery by a physician (2.4 versus midwife), fetal macrosomia (2.4 versus normal weight), and delivery in a delivery room (2.0 versus labor bed). Compared with the risk for whites, significantly increased risk was found for Hispanic (1.9), Filipino (3.7), and Chinese (2.9) women. The practice of prophylactic midline episiotomy is questioned, and suggestions are offered for the design of experimental studies to resolve the questions raised.
分娩期间的直肠损伤是一种可能产生长期致残后果的并发症。有几个因素被认为会影响直肠损伤的风险。其中包括产次、婴儿出生体重以及接生人员实施的各种操作，包括会阴切开术。会阴切开术究竟是预防还是引发直肠括约肌和直肠黏膜撕裂，这一点尤其具有争议性。在一项对2706例自然头位分娩的观察性研究中，采用逻辑分析来确定六个解释性因素中每个因素导致直肠损伤的风险，同时对其他因素进行控制。与未行会阴切开术相比，正中会阴切开术导致直肠损伤的校正风险显著增加（8.9比未行会阴切开术），初产妇（3.3比经产妇）、由医生接生（2.4比助产士）、巨大儿（2.4比正常体重）以及在产房分娩（2.0比产床）。与白人相比，西班牙裔（1.9）、菲律宾裔（3.7）和华裔（2.9）女性的风险显著增加。预防性正中会阴切开术的做法受到质疑，并为设计实验研究以解决所提出的问题提供了建议。
