The Shirodkar operation: a reappraisal

Technique de cerclage prophylactique précoce des cols hypoplasiques après exposition au DES in utero

AIM

Presentation of a prophylactic cerclage technique, placed in the beginning of second trimester of the pregnancy, derived from McDonald cerclage and adapted to hypoplastic cervix following exposure to DES in utero.

MATERIALS AND METHODS

Prospective study including 20 pregnant patients exposed to DES in utero and presenting a hypoplastic cervix. Study of the location of the cerclage tape in the cervix and of changes in cervical length (before and after cerclage) assessed by physical examination of the cervix and by transvaginal ultrasonography.

RESULTS

The cervix was longer after cerclage as shown by physical examination and by ultrasound. The tape was localized near the internal cervical os, its posterior portion nearer the internal cervical os than its anterior portion.

CONCLUSION

This easy-to-perform technique of cerclage of hypoplastic cervix allows the tape to be localized near the internal cervical os without colpotomy and without use of the transabdominal approach, while allowing vaginal delivery.

Comparison of two methods of cervical cerclage by ultrasound cervical measurement

OBJECTIVE

To compare the effects of cerclage performed with a modified Shirodkar procedure or with McDonald's technique using transvaginal ultrasound measurement of the distance between the external os and the suture.

MATERIALS AND METHODS

We performed a retrospective study of all patients who underwent a prophylactic cerclage with either the modified Shirodkar procedure or the McDonald's technique over a 3-year period. Physicians chose the cerclage technique according to their own preferences. Transvaginal ultrasound examination of the cervix was performed 2 weeks after the cerclage to measure its functional length and the distance between the external os and the cerclage.

RESULTS

During the study period, 14 patients had a cerclage with the modified Shirodkar procedure and 19 patients with the McDonald's technique. Twelve of these 33 patients (36.4%) delivered before 37 weeks. The obstetric characteristics of the patients in both groups were similar. There were no significant differences between the Shirodkar and McDonald groups as to the functional cervical length before (31.3 +/- 8.7 vs. 35.6 +/- 9.7 mm, respectively) or after (37.0 +/- 7.3 vs. 36.1 +/- 7.9 mm) cerclage, the distance between the external os and cerclage (16.7 +/- 3.8 vs. 14.0 +/- 5.2 mm), or the number of deliveries before 32 (0 vs. 2) and 34 (1 vs. 3) weeks.

CONCLUSION

The anterior colpotomy of the Shirodkar procedure increased the distance between the external os and the cerclage by a mean of 2.7 mm. This slight gain does not justify exposing the patient to the risks related to this procedure. When cerclage is necessary, McDonald's technique seems preferable.

The 'virtual' cervical internal os: diagnosis during the first trimester of pregnancy

OBJECTIVE

To determine the appropriate time during gestation for assessing the cervix for possible incompetence by ascertaining the gestational week at which the sac reaches the level of the internal os.

METHODS

Three hundred and eighteen women with an intact singleton pregnancy at 5 to 15 weeks' gestation underwent endovaginal sonographic examination to measure the distance between the gestational sac and the cervical internal os. The change in location of the gestational sac in the endometrial cavity over time, and the earliest gestational week at which the gestational sac reached the level of the internal os, were calculated and analyzed with one-way analysis of variance.

RESULTS

The distance between the gestational sac and the 'virtual' cervical internal os decreased from a mean of 4.72 cm at 5 weeks to 1.71 cm at 13 weeks. This distance decreased significantly during the early first trimester (weeks 5 to 7) (P = 0.004), but remained almost unchanged from 12 to 15 weeks. Only at 12 weeks' gestation could the entire cervical length be determined and the configuration of the cervical internal os assessed for incompetence.

CONCLUSIONS

Transvaginal sonography is a good method for evaluating the cervix during pregnancy. The location of the 'virtual' internal os can be determined in the first trimester using the urinary bladder as a reference point.

Abdominal versus vaginal cerclage after a failed transvaginal cerclage: a systematic review

OBJECTIVE

The purpose of this study was to compare the outcomes of pregnancy after transabdominal cerclage versus after transvaginal cerclage in patients with a failed transvaginal cerclage during a previous pregnancy.

STUDY DESIGN

MEDLINE and EMBASE were searched in English. We included studies that reported perinatal and/or maternal outcomes in women who had a transabdominal cerclage or a transvaginal cerclage placed at or before 20 weeks of gestation, after having had a failed nonemergent transvaginal cerclage in a previous pregnancy. Data were included for individual patients if they met the inclusion criteria, and their outcomes were reported separately. We excluded patients with cervical amputation because transvaginal cerclage is not an option for these women because of technical difficulty.

RESULTS

Fourteen studies met the inclusion criteria. Thirteen of the studies were case series (12 retrospective and 1 prospective), and one study was a retrospective cohort study. In total, 157 women in the studies had a failed vaginal cerclage in a previous pregnancy; 117 women had a subsequent transabdominal cerclage; 40 women had a subsequent transvaginal cerclage. The likelihood of perinatal death or delivery at <24 weeks was 6.0% (95% CI, 3.8%-8.2%) after transabdominal cerclage and 12.5% (95% CI, 2.7%-22.7%) after transvaginal cerclage. The likelihood of serious operative complications after transabdominal cerclage was 3.4% (95% CI, 0.01%, 6.8%). There were no serious operative complications after transvaginal cerclage.

CONCLUSION

Transabdominal cerclage may be associated with a lower risk of perinatal death or delivery at <24 weeks of gestation, but it may be associated with a higher risk of serious operative complications. A multicenter randomized controlled trial should be conducted to address this question.

Management of cervical cerclage at term: remove the suture in labor?

OBJECTIVE

To assess the risks and benefits to patients who carry to term after undergoing a Shirodkar cerclage where the cerclage is not removed until the patient presents in labor.

METHODS

A retrospective analysis was conducted examining all patients who underwent a Shirodkar cerclage employing a 5 mm Mersilene band. All the cerclages were placed by a single operator over a twenty five year span, from 1/01/74 till 10/01/98. Only patients who delivered vaginally or were allowed a trial of labor were included. In all cases, the cerclage was removed under regional anesthesia after the patient presented to the hospital in labor.

RESULTS

Ninety six cerclage procedures were performed over that period. Eighty two pregnancies qualified for review. Sixty two patients delivered vaginally (76%). Nine cesareans were indicated for failure to progress in labor (11%) with cervical dystocia possibly implicated in one. There were no cases of ruptured uteri or the development of uterine windows. Of the 82 pregnancies there were five cases (6%) of minor cervical laceration.

CONCLUSION

Allowing patients to proceed to labor with a Shirodkar, cerclage in place, does not increase the risks of cervical dystocia, cervical laceration, or uterine rupture above the reported incidence for these complications in patients in whom the cerclage is removed prophylactically.