Green D C, Moore J M, Adams M M, Berg C J, Wilcox L S, McCarthy B J
Division of Reproductive Health, National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention, Public Health Service, US Department of Health and Human Services, Atlanta, GA, USA.
Am J Epidemiol. 1998 Mar 15;147(6):581-6. doi: 10.1093/oxfordjournals.aje.a009490.
Previous studies of birth certificates have not fully evaluated how accurately they identify delivery methods that have a historical component, such as repeat cesarean and vaginal birth after previous cesarean (VBAC). The authors used linked Georgia birth certificates for first and second deliveries to examine the accuracy of four reported delivery methods in the second pregnancy: vaginal (without previous cesarean), VBAC, primary cesarean, and repeat cesarean, as well as an indicator of a previous cesarean. From the immediate birth certificates, the delivery method for each of the two births was classified as vaginal (V) or cesarean section (CS), which produced possible sequences of V-V, CS-V, V-CS, and CS-CS. The delivery method for the second births to 106,049 women from 1989 through 1992 was reviewed, taking into account the historical information from the linked certificates regarding the first births. Only 42.0% of women with a CS-V sequence were correctly designated on the second birth certificate as a VBAC; 79.3% of women with a V- CS sequence were correctly designated as primary cesarean. From 1980 through 1988, birth certificates contained a check box indicating a previous cesarean (but no VBAC box). During this period, only 75.5% of 25,491 women with a previous cesarean were so designated on the birth certificate. These findings suggest that cross-sectional vital records data substantially underestimate VBAC and primary cesarean rates.
以往对出生证明的研究尚未充分评估其在识别具有历史因素的分娩方式方面的准确性，例如重复剖宫产和剖宫产术后阴道分娩（VBAC）。作者使用佐治亚州首次和第二次分娩的关联出生证明，来检验第二次妊娠中四种报告的分娩方式的准确性：阴道分娩（无既往剖宫产史）、VBAC、初次剖宫产和重复剖宫产，以及既往剖宫产的指标。从即时出生证明来看，两次分娩中每次的分娩方式被分类为阴道分娩（V）或剖宫产（CS），这产生了V-V、CS-V、V-CS和CS-CS的可能序列。回顾了1989年至1992年106,049名女性第二次分娩的分娩方式，并考虑了关联证明中关于第一次分娩的历史信息。在第二次出生证明上，CS-V序列的女性中只有42.0%被正确认定为VBAC；V-CS序列的女性中有79.3%被正确认定为初次剖宫产。1980年至1988年期间，出生证明包含一个表明既往剖宫产的复选框（但没有VBAC框）。在此期间，25,491名有既往剖宫产史的女性中，只有75.5%在出生证明上被如此认定。这些发现表明，横断面生命记录数据大幅低估了VBAC和初次剖宫产率。
