Cervical incompetence: the use of transvaginal sonography to provide an objective diagnosis.

OBJECTIVE: To investigate the use of transvaginal sonography in monitoring the cervix in women at high risk of a preterm delivery. STUDY DESIGN: One hundred and six women at high risk of preterm labor had regular cervical monitoring by transvaginal ultrasound throughout pregnancy from the second trimester to delivery. The study was designed to be observational, but intervention was considered if the cervical length fell below 10 mm. RESULTS: Eleven women demonstrated opening of the cervical canal at rest or with fundal pressure before 24 weeks' gestation. Between 2 and 17 days later all 11 cervices progressively shortened to a cervical length of < 10 mm. Nine women had a cervical cerclage. Seven women had fetal membranes visible within the cervical canal at the time of cerclage. One woman miscarried at 18 weeks, and the other 10 had live births at a median gestational age of 36 (range, 27-38) weeks. CONCLUSIONS: Cervical length shortening in the second trimester, once started, progressed to a cervical length under 10 mm. Opening of the cervical os at rest or in response to fundal pressure detected by transvaginal ultrasound appears to be the early ultrasound feature of cervical incompetence.     

Transvaginal sonographic examination of the cervix in asymptomatic pregnant women: review of the literature.

Different strategies have been developed to refine the prediction of the risk of preterm delivery in asymptomatic patients. Transvaginal sonography has been used for this reason to measure and examine the length and shape of the cervix. In this review, we focus on clinical studies involving transvaginal sonographic assessment of the cervix in asymptomatic women at high risk of preterm delivery and in the general pregnant population. Three ultrasound signs are suggestive of cervical incompetence, namely, dilatation of the internal os, sacculation or prolapse of the membranes into the cervix (with shortening of the functional cervical length) either spontaneously or induced by transfundal pressure, and short cervix in the absence of uterine contractions. Transvaginal sonography has clearly demonstrated that cerclage leads to a measurable increase in cervical length which may contribute to the success of this procedure in reducing the risk of preterm delivery. Several non-randomized interventional studies among patients with cervical incompetence have been published. They have defined a new group of patients requiring cerclage when the women show progressive cervical modifications on transvaginal sonography, while in other studies, cerclage performed on the basis of cervical changes on transvaginal sonography did not prevent premature delivery. One prospective randomized trial in asymptomatic high-risk women has shown two benefits of cerclage following indications for transvaginal sonography: (1) it would generate fewer prophylactic cerclages in high-risk women; (2) therapeutic cerclage before 27 weeks may reduce the incidence of premature delivery before 34 weeks. The risk of preterm delivery is inversely correlated with cervical length. Routine transvaginal sonography of the cervix performed between 18 and 22 weeks can help identify patients at risk of preterm delivery. However, given the low prevalence of preterm births, screening would generate either a high false-positive rate or a low sensitivity. One non-randomized interventional study among patients with a short cervix on routine ultrasound examination found a lower risk of delivery before 32 weeks in the cerclage group than in the expectant management group. However, to date, there have been no prospective randomized trials in a general population. Although evidence is still lacking, there does appear to be a benefit in performing a cerclage rather than continuing with expectant management in cases with sonographic appearance of cervical incompetence in asymptomatic women at high risk of preterm delivery. Ultrasound can be offered to reduce the indications of cerclage for cases in which the situation is uncertain. Within the general obstetric population, transvaginal sonography might help in the selection of asymptomatic but high-risk women. However, the benefit associated with cerclage for sonographic indication has not been demonstrated.     

Elective cerclage vs. ultrasound-indicated cerclage in high-risk pregnancies.

OBJECTIVE: To compare pregnancy outcome after elective vs. ultrasound-indicated cervical cerclage in women at high risk of spontaneous mid-trimester loss or early preterm birth. METHODS: This was a retrospective study comparing two management strategies in women with singleton pregnancies who had at least one previous spontaneous delivery at 16-33 weeks of gestation. One group was managed by the placement of an elective cerclage at 12-16 weeks and the other group had transvaginal ultrasound examinations of the cervix at 12-15+6, 16-19+6, and 20-23+6 weeks and cervical cerclage was carried out if the cervical length was 25 mm or less. RESULTS: A total of 90 patients were examined, including 47 that were managed expectantly and 43 treated by elective cerclage. In the expectantly managed group, 59.6% (28/47) required a cervical cerclage. We excluded from further analysis three patients who were lost to follow-up and three because of fetal death or iatrogenic preterm delivery. Miscarriage or spontaneous delivery before 34 weeks' gestation occurred in 14.6% (6/41) of the elective cerclage group, compared with 20.9% (9/43) in the expectantly managed group (chi2 = 0.219, P = 0.640). CONCLUSION: In women at increased risk of spontaneous mid-trimester or early preterm delivery, a policy of sonographic surveillance followed by cervical cerclage in those with a short cervix reduces the need for surgical intervention without significantly increasing adverse pregnancy outcome.     

Improving the outcome of cervical cerclage by sonographic follow-up

A total of 39 patients with the diagnosis of cervical incompetence were followed up with cervical sonography after placement of prophylactic McDonald cerclage. During the first year of study, 3 out of 12 patients treated with prophylactic cerclage demonstrated funneling of the internal cervical os when examined with cervical sonography; all 3 had premature deliveries. During the last 3 years of the study, 8 of 27 patients treated with prophylactic cerclage demonstrated funneling. With active intervention, neonatal survival improved to 100%. Sonography aids in the management of patients with cervical incompetence and improves outcome even after placement of cervical cerclage.     

Second-trimester uterine artery Doppler and spontaneous preterm delivery.

OBJECTIVE: To assess the relationship between second-trimester uterine artery (UtA) Doppler measurements and spontaneous preterm delivery. METHODS: This was a retrospective analysis of UtA Doppler findings at 18-23 weeks' gestation in 234 singleton pregnancies with spontaneous preterm labor and 5472 pregnancies delivered at term. Cases with fetal chromosomal or structural abnormalities, pre-eclampsia, small-for-gestational-age (SGA) fetuses, concurrent maternal disease, cervical cerclage or history of cone biopsy were excluded. RESULTS: UtA mean resistance index (RI) and number of protodiastolic notches were not significantly different in the spontaneous preterm labor group compared to the normal group. The 62 preterm deliveries not preceded by spontaneous preterm premature rupture of membranes (PPROM) showed a significantly higher RI and prevalence of bilateral notches than cases of preterm deliveries preceded by PPROM (n = 172). However, this difference was not confirmed in a logistic regression model. CONCLUSION: Despite pathological evidence suggesting that defective placentation is associated with spontaneous preterm delivery, second-trimester UtA resistance, as assessed by Doppler ultrasound investigation, is not different in pregnancies subsequently complicated by preterm labor compared to pregnancies delivered at term.     

Ultrasound evaluation of sutures following cervical cerclage for incompetent cervix uteri.

This prospective study was designed to determine whether it is possible to visualize cerclage suture material by ultrasound and to evaluate the clinical usefulness of ultrasound examination after cervical cerclage during pregnancy. Ultrasound examinations demonstrated suture material in all patients in this study. The 5-mm-wide Mersiline tape suture, used in the Shirodkar procedure, was easier to visualize by ultrasound than the no. 2 nylon suture used in the McDonald procedure. Ultrasound examination can be helpful in evaluating the location and effectiveness of the sutures and in detecting protrusion of the membranes beyond the sutures before it is clinically apparent. The sonographic demonstration of the relationship of the protruding membranes to the level of the sutures can be valuable in patient management.     

Funneling to the stitch: an informative ultrasonographic finding after cervical cerclage.

OBJECTIVE: The purpose of this study was to evaluate the utility of ultrasound surveillance after cerclage placement and to propose a rationale for cervical sonography in this setting. SUBJECTS AND METHODS: This was a retrospective analysis of 53 women undergoing cervical cerclage by a maternal-fetal medicine specialist, regardless of indication, and delivering between January 1999 and April 2001. Transvaginal ultrasonographic assessment of cervical length and the degree of cervical funneling after cerclage were compared to preoperative values and to outcomes including gestational age at delivery. Funneling to the cerclage was defined as membranes prolapsing down the endocervical canal until they reached the plane of the cerclage. RESULTS: Cervical cerclage resulted in a significant increase in cervical length from 2.1 +/- 1.2 cm to 2.9 +/- 0.8 cm after the procedure, P < 0.001; however, this measure was not correlated with gestational age at delivery. Funneling to the level of the cerclage was associated with an earlier gestational age at delivery 31.3 +/- 5.6 weeks vs. 36.8 +/- 2.8 weeks for those cases without this finding, P < 0.001. A statistically significant association between funneling to the cerclage and preterm delivery was identified irrespective of the indication (prophylactic or emergency) for the procedure. When descent of the membranes to the level of the cerclage was noted, it occurred by 28 weeks' gestation in all patients studied. The incidence of premature rupture of the membranes was also significantly greater postcerclage in women with descent of the membranes to the cerclage (52%) compared to those without this finding (9%) P= 0.002. CONCLUSIONS: Funneling to the cerclage is significantly associated with earlier preterm delivery in patients who have undergone cervical cerclage. Serial sonography up to 28 weeks' gestation is useful in identifying patients at higher risk for premature rupture of the membranes and preterm delivery.     

The implications of sonographically identified cervical changes in patients not necessarily at risk for preterm birth.

Sonography of the cervix and lower uterine segment has been used in evaluating pregnancies at risk for incompetent cervix and premature labor. Shortened cervix (less than 3 cm) and open internal os with funneling of the membranes into the endocervical canal are sonographic features associated with premature delivery. We identified these sonographic signs in a group of 31 asymptomatic women who were undergoing prenatal sonography for multiple indications, not necessarily related to premature labor or cervical incompetence. Nineteen patients (61%) in this heterogeneous population had pregnancies complicated by preterm labor, clinical evidence of incompetent cervix, or preterm birth. We conclude that the presence of abnormal sonographic features of the cervix seen incidentally during prenatal sonography on asymptomatic patients warrants close clinical attention.     

The cervix as a predictor of preterm delivery in 'at-risk' women.

OBJECTIVE: To examine the relationship between ultrasound-determined cervical status and pregnancy outcome in women 'at-risk' of spontaneous preterm delivery. DESIGN: A prospective cohort study of 120 pregnant women considered to be 'at-risk' of spontaneous preterm delivery by their clinician. Transvaginal ultrasound of the cervix was used to assess overall cervical length, closed endocervical canal length, diameter and internal os dilatation in the second trimester. The main outcome measure was occurrence of spontaneous preterm birth (< 34 and < 37 weeks of gestation). RESULTS: The overall preterm delivery rate (< 37 weeks gestation) in these women was 35% (n = 42) with 20% (n = 24) delivering < 34 weeks gestation. Of the 71 women with a normal cervix, 8 (11%) delivered < 34 weeks, whereas of the 49 women with an abnormal cervix, 16 (33%) delivered < 34 weeks (RR 2.90; 95% CI 1.35-6.24). Using linear regression, closed endocervical canal length of < 21 mm before 20 weeks is associated with delivery < 34 weeks in 95% of women, and with delivery < 37 weeks in 95% of women if the canal length is < 33 mm. Logistic regression showed closed endocervical canal length to be the only significant factor in those women who delivered < 34 weeks after controlling for possible confounders. CONCLUSIONS: A strong relationship is demonstrated between cervical status and pregnancy outcome, particularly the cervical findings before 20 and 24 weeks of gestation. The length of the closed portion of the endocervical canal is the best predictor. A beneficial effect of this approach to 'at-risk' women is the reduction in unnecessary interventions in those with normal cervical findings.     

宫颈环扎术治疗宫颈机能不全妊娠结局

目的探讨宫颈环扎术治疗宫颈机能不全的不同手术时间、手术时机的临床效果及妊娠结局。方法回顾性分析2005年5月至2009年10月22例因宫颈机能不全行宫颈环扎术患者的不同手术时间、手术时机的临床效果及妊娠结局。结果①妊娠12～16周组13例与妊娠17～28周组9例行宫颈环扎术,两组流产、早产、足月产率比较,差异均有统计学意义(P0.05);②紧急宫颈环扎术组8例与择期宫颈环扎术组14例,流产、早产、足月产率比较差异均有统计学意义(P0.05)。结论对有宫颈机能不全者,应在妊娠14～16周择期行宫颈环扎术;对孕前未能诊断宫颈机能不全者,有晚期流产史或早产史的高危孕妇孕中期B超发现宫颈机能不全,行紧急宫颈环扎术,术后加强监测、防止感染亦能取得一定临床效果,降低晚期流产率及早产率。     

Sonographic cervical length in singleton pregnancies with intact membranes presenting with threatened preterm labor.

OBJECTIVE: Less than 10% of women presenting with preterm contractions progress to active labor and delivery. This study investigates whether cervical length measurements by ultrasound can discriminate between true and false labor in women presenting with threatened preterm labor. METHODS: Cervical length was measured by transvaginal ultrasound in 253 women with singleton pregnancies presenting with painful uterine contractions at a median age of 31 (range, 24-35) weeks of gestation. Women presenting in active labor, defined by the presence of cervical dilatation of >or = 3 cm, those with ruptured membranes and those that underwent prior or subsequent cervical cerclage were excluded from the study. The clinical management was determined by the attending obstetrician without taking into account the cervical length. Primary outcome of the study was delivery within 7 days of presentation based on the results of randomized studies on the use of tocolytics in women with preterm labor that reported a prolongation of pregnancy by 7 days. RESULTS: Delivery within 7 days of presentation occurred in 21/253 (8.3%) pregnancies and this was inversely related to cervical length. Receiver-operating characteristics (ROC) curves established a cervical length of 15 mm as the most relevant cut-off level for the prediction of preterm delivery within 7 days. In 217 cases the cervical length was > or = 15 mm and only four of these (1.8%) delivered within 7 days. In the 36 women with cervical length < 15 mm, delivery occurred in 17 (47.2%) within 7 days. Logistic regression analysis demonstrated that significant independent contribution in the prediction of delivery within 7 days was provided by cervical length, contraction frequency at presentation, previous history of preterm delivery and vaginal bleeding. There was no significant contribution from gestation at presentation, ethnic origin, maternal age, parity, cigarette smoking or the administration of tocolysis, antibiotics or steroids. Similar results were shown in a subanalysis of 162 patients presenting at a gestational age below 32 weeks: 9/19 patients (47.4%) with a cervical length below 15 mm delivered within 7 days compared to 3/143 (2.1%) with a cervical length > or = 15 mm. Univariate as well as multivariate analyses confirmed cervical length to be a significant independent predictor of delivery within 7 days in this population. CONCLUSIONS: Sonographic measurement of cervical length helps to avoid overdiagnosis of preterm labor in women with preterm contractions and intact membranes.     

Cervicovaginal fistulas: management of subsequent pregnancy

Cervicovaginal fistulas that develop after midtrimester abortion represent a significant risk to subsequent pregnancies. Since patients with this condition appear to be at increased risk for preterm labor and cervical incompetence, I recommend a cerclage procedure. The probability of complications during labor in such cases makes elective cesarean delivery the method of choice.     

Prediction of preterm premature rupture of membranes by transvaginal ultrasound features and risk factors in a high-risk population.

OBJECTIVE: To determine the transvaginal ultrasound features and risk factors that predict preterm delivery (PTD) preceded by either preterm premature rupture of membranes (PPROM) or preterm labor (PTL) in a high-risk population. STUDY DESIGN: Singleton gestations at high-risk for preterm delivery were screened prospectively with transvaginal ultrasound between 14 and 24 weeks. Univariate and multivariate regression analyses were performed for historical obstetric risk factors and transvaginal ultrasound features (cervical length (CL) and cervical funneling (CF)) for the prediction of PTD preceded by PPROM or PTL at < 32 and < 35 weeks' gestation, respectively. Indicated preterm deliveries were excluded. RESULTS: Of 321 patients screened, 71 (22%) delivered at < 35 weeks, 40 (56%) after PPROM and 31 (44%) after PTL. Preterm delivery at < 32 weeks was seen in 47 patients (15%), with 20 (43%) occurring after PTL and 27 (57%) after PPROM. Univariate analysis showed the following to be significant predictors of PPROM at < 35 weeks: a past history of PTD between 25 and 30 weeks (P < 0.008), cerclage in the current pregnancy (P < 0.0001), bacterial vaginosis (P < 0.011), CL < 25 mm (P < 0.0001) and CF > 25% (P < 0.0001). The following were found to be significant predictors of PTL at < 35 weeks: black race (P < 0.02), a cerclage in the current pregnancy (P < 0.01), CL < 25 mm (P < 0.001) and CF > 25% (P < 0.0001). The significant predictors of PPROM at < 32 weeks were cerclage in the current pregnancy (P < 0.006) and CL < 25 mm (P < 0.0001); for PTL at < 32 weeks they were a past history of spontaneous miscarriage between 14 and 24 weeks (P < 0.02), black race (P < 0.021), cerclage in the current pregnancy (P < 0.001) and CL < 25 mm (P < 0.001). Multivariate regression analysis revealed the significant predictors of PPROM at < 35 weeks to be: a history of PTD between 25 and 30 weeks with odds ratio (OR) 4.8 (95% confidence interval (CI), 1.9-11.5) and CL < 25 mm with OR 7.9 (95% CI, 3.6-17.5). The significant predictors of PTL at < 35 weeks on multivariate regression were black race with OR 2.2 (95% CI, 1.0-4.8) and unemployment with OR 1.2 (95% CI, 1.0-1.5). For deliveries < 32 weeks, CL < 25 mm (OR, 10.1; 95% CI, 3.2-32) was the only significant predictor of PPROM. Significant predictors of PTL were unemployment (OR, 1.3; 95% CI, 1.1-1.7), a history of spontaneous miscarriage between 14 and 24 weeks (OR, 6.2; 95% CI, 1.4-25), black race (OR, 8.6; 95% CI, 1.5-47) and CL < 25 mm (OR, 4.4; 95% CI, 1-19). The sensitivity, specificity and positive and negative predictive values of CL < 25 mm for PPROM at < 35 weeks were 73%, 69%, 25% and 95%, respectively; for PTL at < 35 weeks they were 58%, 66%, 15% and 94%; for PPROM at < 32 weeks they were 85%, 68%, 20%, and 98%; for PTL at < 32 weeks they were 70%, 66%, 12% and 97%. CONCLUSION: There are differences in both transvaginal ultrasound findings and risk factors that predict PPROM or PTL. Of the pathways leading to PTD, CL was a more significant predictor of PPROM compared with PTL, while sociodemographic factors were more predictive of PTL.     

超声评估非孕期宫颈机能不全研究进展

宫颈在妊娠和分娩中发挥关键作用，宫颈机能不全（CIC）可导致女性出现反复流产及早产。孕前评估宫颈机能是可使备孕女性避免不良妊娠结局的重要保障，超声则是评估宫颈机能不全的常用方法。本文对超声评估非孕期宫颈机能不全研究进展进行综述。     

Cervical length and funneling at 23 weeks of gestation in the prediction of spontaneous early preterm delivery.

OBJECTIVES: To establish the relationship of cervical length at 23 weeks of gestation to the risk of spontaneous delivery before 33 weeks and to determine the possible additional risk if funneling is present. METHODS: During a 36-month period, 6819 women with singleton pregnancies underwent transvaginal sonographic cervical assessment at 22-24 weeks as a screening test for preterm delivery. The distribution of cervical length and the prevalence of funneling, defined as dilatation of the internal os of > or = 5 mm in width, were established. Women who underwent cervical cerclage, iatrogenic preterm delivery or were lost to follow-up were excluded from further analysis. In the remaining 6334 pregnancies, logistic regression was used to examine the contribution of cervical length and funneling to the risk of spontaneous preterm delivery before 33 weeks. RESULTS: The median cervical length was 36 mm and in 1.6% of cases the length was < or = 15 mm. There was a significant inverse association between cervical length and percentage rate of spontaneous delivery before 33 weeks. Funneling of the internal os was present in about 4% of pregnancies and the prevalence decreased with increasing cervical length from 98% when the length was < or = 15 mm to about 25% for lengths of 16-30 mm and less than 1% at lengths of > 30 mm. The rate of preterm delivery was 6.9% in those with funneling compared to 0.7% in those without funneling (chi2 = 86.7; P < 0.0001). However, logistic regression analysis demonstrated that funneling did not provide a significant additional contribution to cervical length in the prediction of spontaneous delivery before 33 weeks (odds ratio for short cervix = 24.9, Z = 4.43, P < 0.0001; odds ratio for funneling = 1.8, Z = 0.84, P = 0.40). CONCLUSION: In the prediction of preterm delivery, funneling does not provide any significant contribution in addition to cervical length.     

Cervical Incompetence Prevention Randomized Cerclage Trial (CIPRACT): effect of therapeutic cerclage with bed rest vs. bed rest only on cervical length.

OBJECTIVE: To compare the effects of therapeutic cerclage and bed rest vs. just bed rest on cervical length and to relate these effects to the risk of preterm delivery. DESIGN: Cervical length was measured in patients at high risk of cervical incompetence. When a cervical length < 25 mm was measured before 27 weeks' gestation, randomization for therapeutic cerclage and bed rest vs. just bed rest was performed. After randomization, cervical length was measured weekly. For statistical analysis, t-test and Fisher's exact tests were used and P < 0.05 was considered statistically significant. RESULTS: Nineteen women were randomly allocated to receive a therapeutic cerclage and bed rest and 16 were allocated to receive bed rest only. Mean cervical lengths and mean gestational ages before randomization were comparable between both groups, overall 19.8 mm and 20.7 weeks. Cervical length was measured again at a mean gestation of 22.1 weeks. Mean cervical length (31 mm) was significantly (P < 0.0001) longer after cerclage than after bed rest only (19 mm). A cervical length > or = 25 mm was measured in 22 of the 35 included women, 16 in the cerclage group and six in the bed-rest group (P = 0.006). Of these 22 women, only one delivered before 34 weeks' gestation, which was significantly less frequent than six out of 13 women with a cervical length < 25 mm (P = 0.006). CONCLUSIONS: Therapeutic cerclage with bed rest increases cervical length more often than bed rest alone. A postintervention cervical length > or = 25 mm reduces the risk of preterm delivery in women at high risk of cervical incompetence and a preintervention cervical length < 25 mm.     

孕期宫颈环绕缝合术的围术期护理

[目的]总结孕期宫颈环绕缝合术的围术期护理。[方法]回顾分析33例病人的临床资料,重点进行心理护理、病情观察、用药观察以及饮食、大小便护理、健康指导。[结果]全部病例平安度过围术期,无并发症,32例保胎至足月分娩,1例33周孕早产。[结论]合理的围术期护理是保障手术及妊娠成功的关键。     

Early prediction of preterm delivery by transvaginal ultrasonography.

The clinical value of transvaginal ultrasonography in the evaluation of the uterine cervix of pregnant women was studied. Comparison with conventional transabdominal ultrasound in 24 pregnant subjects revealed that transvaginal ultrasound was superior, because the transabdominal technique usually requires a full bladder, which causes deformation and elongation of the cervix. Digital examination showed dilatation of the internal os in only ten (38.5%) of 26 patients in whom it had previously been shown by transvaginal sonography. Transvaginal ultrasonography has the advantage of providing natural and objective information on the cervix. The values of three sonographic signs found transvaginally for predicting preterm delivery were evaluated in a total of 130 at-risk patients and 129 control subjects. Shortening of the cervical length by -1.5 SD or more was associated with an increased risk of preterm delivery (11.3% vs. 2.8%, p < 0.01). A dilated internal os of more than 5 mm before 30 weeks of gestation was associated with preterm delivery more often than an undilated internal os (33.3% vs. 3.5%, p < 0.01). Dynamic changes in the degree of dilatation of the cervical canal which were found in nine women were significantly related with preterm delivery (p < 0.05). But, in the at-risk group, only dilatation of the internal os had a predictive value for preterm birth. From these data, dilatation of the internal os on transvaginal ultrasonography was proved to be an early and important predictor of preterm delivery.     

宫颈机能不全紧急环扎术的效果评估——附20例临床分析

目的：探讨宫颈紧急环扎术治疗宫颈机能不全（cervical incompetence,CI）的效果。方法：将我院2005-06-2009-12收治妊娠期宫颈机能不全患者20例分为：选择性环扎组7例,紧急环扎组7例,另外6例纳入保守治疗组作为对照（简称对照组）。入院后完善相关检查,全部手术组实施宫颈环扎术及药物保胎治疗,对照组仅给予保胎药物治疗。上述处理后观察5～7d,无流产征兆者出院,规律产检,随访至妊娠终止。观察其平均保胎天数、新生儿出生体重、新生儿存活、〉34周分娩、〉37周分娩、胎膜早破发生情况,对结果进行统计分析。结果：保胎天数：选择性环扎组（154.86±10.51）d,紧急环扎组（34.86±46.84）d,对照组（94.75±30.93）d;新生儿平均出生体重：选择性环扎组（3171.43±424.12）g,紧急环扎组（1557.14±907.11）g,对照组（2812.50±383.79）g;新生儿存活：选择性环扎组7例,紧急环扎组2例,对照组6例;〉34周者分娩：选择性环扎组7例,紧急环扎组2例,对照组6例;〉37周分娩：选择性环扎组4例,紧急环扎组1例,对照组3例;胎膜早破的发生：选择性环扎组0例,紧急环扎组4例,对照组0例。结论：宫颈机能不全是导致妊娠晚期流产和早产的常见原因,预防性宫颈环扎可延长保胎天数、增加〉34周分娩、减少胎膜早破的发生、增加新生儿平均出生体重,但并不能减少早产的发生。对CI的低危患者,保守治疗也能取得较好的妊娠结局和新生儿结局。     

宫颈环扎术治疗宫颈机能不全的临床研究

目的：探讨宫颈环扎术治疗宫颈机能不全的疗效。方法：分析1996年1月—2009年12月79例因宫颈机能不全行宫颈环扎术患者的临床资料。结果：（1）79例宫颈机能不全患者中76例获得活婴,3例失败,手术总成功率为96.20%。其中26例行选择性宫颈环扎术,成功25例,失败1例。44例行治疗性宫颈环扎术,无一例失败。9例行急诊宫颈环扎术,成功7例,失败2例,成功率为77.78%,明显低于非急诊宫颈环扎术的成功率（96.15%）。（2）与孕20周后相比,孕20周前行选择性环扎术者妊娠天数和新生儿出生体质量明显增加（261.83±9.89d比243.64±26.04d;3106.67±423.14g比2550.36±792.68g）。（3）在治疗性宫颈环扎组和选择性环扎术组中,有3次以上流产史者宫颈环扎后分娩时妊娠天数和新生儿出生体质量明显高于流产次数少于3次者（261.50±10.97d比237.10±27.05d;3025.00±524.81g比2458.50±818.63g）。结论：宫颈环扎术治疗宫颈机能不全疗效肯定;急诊宫颈环扎术是可行的,它可以明显改善宫颈机能不全患者的预后;在孕20周前行选择性环扎术可以明显增长分娩孕周和增加新生儿出生体质量;无论是选择性还是治疗性宫颈环扎,流产3次以上的患者更能从手术中获益。