Volume 163 Number 2
Leiters
gynecologists may choose to develop adequate expertise to read their own mammography films. This issue should not be considered a turf battle between our two disciplines. Most gynecologists are more than horrified by their already existing medical liability situations and will not wish to expand it even further into the legally volatile diagnosis of breast cancer. At the same time, I cannot understand the apparent sensitivities expressed in the letter by Drs. Dodd and McLelland. Radiologists have no hesitation to enter practice areas of other specialties when they believe that a patient benefit can. be obtained. When this recently happened in an area of gynecology, lour community welcomed our radiology colleagues with open arms? We should expect the same. Norbert Gleicher, MD Department of Obstetrics and Gynecology, Mount Sinai Hospital Medical Center of Chicago , Chicago, IL 60608
REFERENCES I . Thurmond A, Novy M, Uchida B, Rosch J. Fallopian tube obstruction : selective salpingography and recanalization . Radiology 1987;163:511. 2. Thurmond A, RoschJ , Uchida B. Radiologic fallopian tube catheterization. Film presentation FP-02, at the forty-fifth annual meeting of the American Fertility Society, San Francisco, California, November 13-16, 1989.
Vaginal birth after cesarean section: An appraisal of the reappraisal To the Editors: Drs. Yetman and Nolan recently reported on attempted vaginal birth after cesarean section in 224 women (Yetman Tj, Nolan TE. Vaginal birth after cesarean section: a reappraisal of risk. AM j OBSTET GyNECOL 1989;161:1119-23). I am concerned that some of the conclusions reached in this study may not be supported by the data presented. The authors concluded that "women who consider vaginal birth after cesarean section should be counseled with regard to the increased risk of perineal trauma." This recommendation was based on the finding of fewer lacerations in a group of women with no prior cesarean operations. Although it is almost inconceivable that an abdominal operation could predispose the perineum to trauma in a subsequent labor, it may be hypothesized that among women who undergo an initial cesarean section there exists a subgroup of women who are in some way predisposed to later perineal trauma. However, I believe there is a much more straightforward explanation for this study's findings. The 224 patients in the trial of labor group were studied by obtaining their inpatient records and meticulously searching for complications. In contrast, the 6957 patients in the control group were studied by scanning for comments in labor and delivery logbooks. This introduces substantial bias into the study. It is almost certain that actual review of the thousands of control patient' charts would have revealed large numbers of lacerations that were not recorded in the labor logbooks. The authors also concluded: "Estimates of fetal weight at term should be a part of the decision-making
691
process before vaginal birth after cesarean section is attempted." However, several recent studies have cautioned that current technology cannot accurately identify macrosomic infants before birth. I This is true even when the most sophisticated ultrasound techniques and computerized analysis are available. 2 But what if fetal macrosomia could be predicted accurately? The study's finding that infants weighing < 3720 gm are more likely to be delivered vaginally than those weighing >3720 gm would still be clinically meaningless. Large babies are more likely to be delivered by cesarean section than small ones. It would have been surprising if this did not apply for the prior cesarean group. In light of the admittedly strict criteria used to diagnose arrest of dilatation, it is remarkable that 47% of the women with infants >3720 gm were able to avoid repeat cesarean operations. In any case the fetal weight recommendation was based on the observation of only 73 cases with fetal weight >3720 gm . A review of our data base reveals 1860 such cases, and 1238 (67 %) of these women had successful vaginal births. We recently reported the outcomes of 30 1 trials of labor with infant birth weights > 4000 gm. 3 The majority of these women were delivered vaginally. Two perinatal deaths occurred in the study by Yetman and Nolan. It should be emphasized that neither case was related to a previous uterine scar. These cases may emphasize the risks of postterm pregnancy, but they do not pertain to vaginal birth after cesarean section. Although the authors found it "sobering" to note that these cases might have been prevented by elective cesarean section at term , the same statement could be made about every postterm fetal death in America. Finally, it was perplexing that the authors considered a mandatory trial of labor (in the absence of medical contraindications) to be a "quick-fix" measure. If they meant to imply that current trial of labor recommendations were formulated in haste, I would like to remind them that National Institutes of Health and American College of Obstetricians and Gynecologists guidelines were based on the reassuring results of more than 40 studies published over the past 50 years.' It is clear that widespread acceptance of vaginal birth after cesarean section could quickly eliminate the need for a large portion of the I million cesarean operations performed in this country every year. Bruce L. Flamm, MD Department of Obstetrics and Gynecology, Kaiser-Permanente Medical Center, 10800 Magnolia Ave., Riverside, CA 92505
REFERENCES I. Benacerraf BR, Gelman R, Frigoletto FD. Sonographically estimated fetal weights: accuracy and limitation. AM J OsSTET GYNECOL 1988;159:1118-21. 2. Miller JM, Brown HL, Khawli OF, Pastored JG, Gabert HA. Ultrasonographic identification of the macrosomic fetus. AMJ OSSTET GYNECOL 1988;159:1110-4. 3. Flamm BL, Goings JR. Vaginal birth after c
Leiters
gynecologists may choose to develop adequate expertise to read their own mammography films. This issue should not be considered a turf battle between our two disciplines. Most gynecologists are more than horrified by their already existing medical liability situations and will not wish to expand it even further into the legally volatile diagnosis of breast cancer. At the same time, I cannot understand the apparent sensitivities expressed in the letter by Drs. Dodd and McLelland. Radiologists have no hesitation to enter practice areas of other specialties when they believe that a patient benefit can. be obtained. When this recently happened in an area of gynecology, lour community welcomed our radiology colleagues with open arms? We should expect the same. Norbert Gleicher, MD Department of Obstetrics and Gynecology, Mount Sinai Hospital Medical Center of Chicago , Chicago, IL 60608
REFERENCES I . Thurmond A, Novy M, Uchida B, Rosch J. Fallopian tube obstruction : selective salpingography and recanalization . Radiology 1987;163:511. 2. Thurmond A, RoschJ , Uchida B. Radiologic fallopian tube catheterization. Film presentation FP-02, at the forty-fifth annual meeting of the American Fertility Society, San Francisco, California, November 13-16, 1989.
Vaginal birth after cesarean section: An appraisal of the reappraisal To the Editors: Drs. Yetman and Nolan recently reported on attempted vaginal birth after cesarean section in 224 women (Yetman Tj, Nolan TE. Vaginal birth after cesarean section: a reappraisal of risk. AM j OBSTET GyNECOL 1989;161:1119-23). I am concerned that some of the conclusions reached in this study may not be supported by the data presented. The authors concluded that "women who consider vaginal birth after cesarean section should be counseled with regard to the increased risk of perineal trauma." This recommendation was based on the finding of fewer lacerations in a group of women with no prior cesarean operations. Although it is almost inconceivable that an abdominal operation could predispose the perineum to trauma in a subsequent labor, it may be hypothesized that among women who undergo an initial cesarean section there exists a subgroup of women who are in some way predisposed to later perineal trauma. However, I believe there is a much more straightforward explanation for this study's findings. The 224 patients in the trial of labor group were studied by obtaining their inpatient records and meticulously searching for complications. In contrast, the 6957 patients in the control group were studied by scanning for comments in labor and delivery logbooks. This introduces substantial bias into the study. It is almost certain that actual review of the thousands of control patient' charts would have revealed large numbers of lacerations that were not recorded in the labor logbooks. The authors also concluded: "Estimates of fetal weight at term should be a part of the decision-making
691
process before vaginal birth after cesarean section is attempted." However, several recent studies have cautioned that current technology cannot accurately identify macrosomic infants before birth. I This is true even when the most sophisticated ultrasound techniques and computerized analysis are available. 2 But what if fetal macrosomia could be predicted accurately? The study's finding that infants weighing < 3720 gm are more likely to be delivered vaginally than those weighing >3720 gm would still be clinically meaningless. Large babies are more likely to be delivered by cesarean section than small ones. It would have been surprising if this did not apply for the prior cesarean group. In light of the admittedly strict criteria used to diagnose arrest of dilatation, it is remarkable that 47% of the women with infants >3720 gm were able to avoid repeat cesarean operations. In any case the fetal weight recommendation was based on the observation of only 73 cases with fetal weight >3720 gm . A review of our data base reveals 1860 such cases, and 1238 (67 %) of these women had successful vaginal births. We recently reported the outcomes of 30 1 trials of labor with infant birth weights > 4000 gm. 3 The majority of these women were delivered vaginally. Two perinatal deaths occurred in the study by Yetman and Nolan. It should be emphasized that neither case was related to a previous uterine scar. These cases may emphasize the risks of postterm pregnancy, but they do not pertain to vaginal birth after cesarean section. Although the authors found it "sobering" to note that these cases might have been prevented by elective cesarean section at term , the same statement could be made about every postterm fetal death in America. Finally, it was perplexing that the authors considered a mandatory trial of labor (in the absence of medical contraindications) to be a "quick-fix" measure. If they meant to imply that current trial of labor recommendations were formulated in haste, I would like to remind them that National Institutes of Health and American College of Obstetricians and Gynecologists guidelines were based on the reassuring results of more than 40 studies published over the past 50 years.' It is clear that widespread acceptance of vaginal birth after cesarean section could quickly eliminate the need for a large portion of the I million cesarean operations performed in this country every year. Bruce L. Flamm, MD Department of Obstetrics and Gynecology, Kaiser-Permanente Medical Center, 10800 Magnolia Ave., Riverside, CA 92505
REFERENCES I. Benacerraf BR, Gelman R, Frigoletto FD. Sonographically estimated fetal weights: accuracy and limitation. AM J OsSTET GYNECOL 1988;159:1118-21. 2. Miller JM, Brown HL, Khawli OF, Pastored JG, Gabert HA. Ultrasonographic identification of the macrosomic fetus. AMJ OSSTET GYNECOL 1988;159:1110-4. 3. Flamm BL, Goings JR. Vaginal birth after c
