Short cervix on ultrasound: does indomethacin prevent preterm birth?

OBJECTIVE: Our aim was to estimate if indomethacin therapy prevents preterm birth (PTB) in women with a short cervical length (CL) on transvaginal ultrasound (TVU). STUDY DESIGN: Individual-level data from all randomized trials including asymptomatic women with a short CL on TVU were analyzed for use of indomethacin at the time of the short CL. The trials eligible would be ones that randomized women with a short CL <25 mm, identified between 14 and 27 weeks. The eligible trials randomized such women to receive either cerclage or no cerclage. Only women who did NOT receive cerclage were analyzed. Exclusion criteria were major fetal anomaly and cerclage. We compared demographics, risk factors, and outcomes in women who, at the time of the short CL, received indomethacin or not. Primary outcome was PTB <35 weeks. RESULTS: Three of the 4 randomized trials identified had databases which recorded indomethacin use at the time of the short CL. A total of 139 women with a short CL <25 mm identified at 14 to 27 weeks were identified. Of these women, 99 (71.2%) received indomethacin, and 40 (28.8%) did not. Demographics and risk factors, including previous PTB (45.5% vs 62.5%; P = .11), were similar in the 2 groups. The primary outcome of PTB <35 weeks occurred in 29.3% (29/99) of women who received indomethacin, and 42.5% (17/40) of women who did not receive indomethacin (RR 0.69, 95% CI 0.44-1.13). PTB <24 weeks occurred in 1.0% (1/99) versus 7.5% (3/40), respectively (RR 0.14; 95% CI 0.02-0.92). Incidence of perinatal death was similar in the 2 groups (6% vs 10%; RR 0.61, 95% CI 0.19-1.95). CONCLUSION: Indomethacin therapy for asymptomatic women who have a short CL <25 mm on TVU at 14 to 27 weeks and do not receive a cerclage did not prevent spontaneous PTB <35 weeks, but did prevent PTB <24 weeks. Further research including larger numbers and a randomized trial design is necessary to further clarify the effectiveness as well as the risks of this therapy.

Cerclage for short cervix on ultrasonography: meta-analysis of trials using individual patient-level data.

OBJECTIVE: Preterm birth is the main cause of perinatal morbidity and mortality. A short cervical length on transvaginal ultrasonography predicts preterm birth. Our aim was to estimate by meta-analysis of randomized trials whether cerclage prevents preterm birth in women with a short cervical length. DATA SOURCES: MEDLINE, PubMed, EMBASE, and the Cochrane Library were searched with the terms "cerclage," "cervical cerclage," "short cervix," "ultrasound," and "randomized trial." We included randomized trials involving the use of cerclage in women with short cervical length on transvaginal ultrasonography using patient-level data. TABULATION, INTEGRATION, AND RESULTS: Four properly conducted trials were identified. In the total population, preterm birth at less than 35 weeks of gestation occurred in 29.2% (89/305) of the cerclage group, compared with 34.8% (105/302) of the no-cerclage groups (relative risk [RR] 0.84, 95% confidence interval [CI] 0.67-1.06). There was no significant heterogeneity in the overall analysis (P = .29). There was a significant reduction in preterm birth at less than 35 weeks in the cerclage group compared with the no-cerclage groups in singleton gestations (RR 0.74, 95% CI 0.57-0.96), singleton gestations with prior preterm birth (RR 0.61, 95% CI 0.40-0.92), and singleton gestations with prior second-trimester loss (RR 0.57, 95% CI 0.33-0.99). There was a significant increase in preterm birth at less than 35 weeks in twin gestations (RR 2.15, 95% CI 1.15-4.01). CONCLUSION: Cerclage does not prevent preterm birth in all women with short cervical length on transvaginal ultrasonography. In the subgroup analysis of singleton gestations with short cervical length, especially those with a prior preterm birth, cerclage may reduce preterm birth, and a well-powered trial should be carried out in this group of patients. In contrast, in twins, cerclage was associated with a significantly higher incidence of preterm birth.

Cervical incompetence: a reappraisal of an obstetric controversy.

UNLABELLED: Cervical incompetence is not a categoric but rather a continuous variable, meaning that there are various degrees in the competency of the cervix. Furthermore, a certain degree of competency of the cervix can be expressed differently in subsequent pregnancies. Women with risk factors for cervical incompetence in their gynecological/obstetric history should be followed by transvaginal ultrasonography. History alone is not an indication for a prophylactic cerclage. Although transvaginal ultrasonography identifies women at high risk of preterm delivery, it does not discriminate between different underlying pathologies. Short cervical length alone is not an indication for a therapeutic cerclage. Serial transvaginal ultrasonographic measurements of cervical length in women with risk factors can identify those women truly at high risk of preterm delivery. A transvaginal cervical cerclage with bed rest reduces preterm delivery and improves perinatal outcome in women with a short cervical length and risk factors for cervical incompetence. TARGET AUDIENCE: Obstetricians & Gynecologists, Family Physicians. LEARNING OBJECTIVES: After completion of this article, the reader will be able to define cervical incompetence, explain the role of transvaginal ultrasonography in the prediction of preterm delivery, and summarize the data on the use of transvaginal cervical cerclage.

Shirodkar versus McDonald cerclage for the prevention of preterm birth in women with short cervical length.

The efficacy of Shirodkar cerclage was compared with that of the McDonald procedure for the prevention of preterm birth (PTB) in women with a short cervix. Secondary analysis using data from all published randomized trials including women with a short cervical length (CL) was performed comparing the use of Shirodkar versus McDonald sutures. Analysis was limited to singletons with short CL on transvaginal ultrasound. The primary outcome measure was PTB < 33 weeks. Statistical analysis was performed using bivariate and multivariable techniques. From 607 women randomly assigned in the study, 277 met our inclusion criteria; 127 received Shirodkar and 150 women received McDonald sutures. The mean ( +/- standard deviation) gestational age at delivery was 35.0 +/- 5.3 versus 36.3 +/- 4.7 for the Shirodkar versus McDonald groups, respectively ( p< 0.02). PTB < 33 weeks was seen in 61 (22%) of 277 women; 26 (20%) of 127 in the Shirodkar and 35 (23%) of 150 in the McDonald groups, respectively (odds ratio [OR], 0.85; 95% confidence interval [CI], 0.5 to 1.6). On adjusting for confounders using logistic regression modeling, no significant difference in PTB < 33 weeks was found between the two groups (OR, 0.55; 95% CI, 0.2 to 1.3). In women with short cervical length randomly assigned to receiving cerclage, no significant difference in prevention of PTB was observed using Shirodkar or McDonald's procedures.

The short and funneling cervix: when to use cerclage?

PURPOSE OF REVIEW: The diagnosis of cervical incompetence remains extremely difficult because there is no diagnostic test available prior to, during or after pregnancy. This review will summarize the latest publications on the use of transvaginal ultrasonography to identify women at high risk of preterm delivery and the use of cervical cerclage in these women. RECENT FINDINGS: Cervical length is not only inversely related to the risk of preterm delivery but also inversely related to the risk of intrauterine infection in women with preterm labor. Furthermore, previous history of preterm delivery is related to the risk of preterm delivery. Cerclage trials on women with short cervical length present conflicting results both in low and high-risk populations. Assessment of risk factors and obstetric history remain important in the diagnosis of cervical incompetence. Women at high risk of preterm delivery due to cervical incompetence should be followed-up with transvaginal measurements of cervical length. Only a minority of these women will develop a short cervical length and will consequently be at high risk of preterm delivery. SUMMARY: A combination of assessment of risk factors, obstetric history and follow-up of cervical length enables us to identify women who benefit from a cervical cerclage.

Strategies for prevention--cervical cerclage.

Transvaginal cervical cerclage was introduced as a treatment for cervical incompetence in 1951. Over the years, our understanding of this clinical entity has changed tremendously, which has implications for obstetric management. This review focuses on the obstetric management of women considered to be at high risk of preterm delivery due to cervical incompetence at different stages of pregnancy.

Cervical incompetence prevention randomized cerclage trial: emergency cerclage with bed rest versus bed rest alone.

OBJECTIVE: The purpose of this study was to compare preterm delivery rates and neonatal morbidity/mortality rates for women with cervical incompetence with membranes at or beyond a dilated external cervical os that was treated with emergency cerclage, bed rest plus indomethacin, versus just bed rest. STUDY DESIGN: Women with cervical incompetence with membranes at or beyond a dilated external cervical os, before 27 weeks of gestation, were treated with antibiotics and bed rest and randomly assigned for emergency cerclage and indomethacin or bed rest only. RESULTS: Twenty-three women were included; 13 women were allocated randomly to the emergency cerclage and indomethacin group, and 10 women were allocated randomly to the bed rest-only group. Gestational age at time of randomization was 22.2 weeks in the emergency cerclage and indomethacin group and 23.0 weeks in the bed rest-only group. Mean interval from randomization until delivery was 54 days in the emergency cerclage and indomethacin group and 20 days in the bed rest-only group (P=.046). Mean gestational age at delivery was 29.9 weeks in the emergency cerclage and indomethacin group and 25.9 weeks in the bed rest-only group. Preterm delivery before 34 weeks of gestation was significantly lower in the emergency cerclage and indomethacin group, with 7 of 13 deliveries versus all 10 deliveries in the bed rest-only group (P=.02). CONCLUSIONS: Emergency cerclage, indomethacin, antibiotics, and bed rest reduce preterm delivery before 34 weeks compared with bed rest and antibiotics alone.