Sonographic Assessment of Cervical Length and the Risk of Preterm Birth

The Short Cervix: A Critical Analysis of Diagnosis and Treatment

A short cervix in the second trimester is a significant risk factor for spontaneous preterm birth, preterm prelabor rupture of membranes, and subsequent adverse perinatal outcome. The pathophysiology is complex and multifactorial with inflammatory and/or infectious processes often involved. Biomarkers have been developed in an effort to predict preterm birth with varying degrees of success. The treatment options of cerclage, progesterone, pessary, and combination therapy are reviewed. Evidence-based protocols are summarized for singleton and multiple gestation.

The prevalence of cervical insufficiency in Chinese women with polycystic ovary syndrome undergone ART treatment accompanied with negative prognosis: a retrospective study

The objective of this study was to explore the correlation between cervical insufficiency (CI) and polycystic ovary syndrome (PCOS) in Chinese women undergoing assisted reproductive technology (ART) treatment. The retrospective study enrolled 2978 women including 1489 with PCOS and 1489 without PCOS, among which 34 women were diagnosed with CI (1.14%). The prevalence of CI in PCOS women was statistically higher than that in women without PCOS. Among those women with CI, 23 cases exhibited PCOS, and those cases had an average gestational age of 26.09 ± 5.91 weeks at the end of pregnancy, which was earlier than that of women without PCOS, and the pregnancy outcomes were worse than in the non-PCOS group though not statistically significant. Multivariable logistic regression showed that PCOS status (odds ratio: 2.050, 95% confidence interval: 1.009-4.206) were associated with increased risk of CI. Our study revealed that among those Chinese women who conceived by ART treatment, the prevalence of CI in women with PCOS was higher than that in women without PCOS. Co-morbidity of CI with polycystic ovarian syndrome negatively impacts prognosis.Impact statementWhat is already known on this subject? Women with PCOS have a higher rate of adverse obstetrical outcomes than women without PCOS.What the results of this study add? Women with PCOS were more likely to have pregnancies complicated with CI. Co-morbidity of cervical incompetence with PCOS negatively impacts prognosis.What the implications are of these findings for clinical practice and/or further research? Given these results, close surveillance of cervical changes during the second trimester in women with PCOS is necessary for reducing the risk of miscarriage related to CI.

The efficacy of cervical cerclage combined with a pessary for the prevention of spontaneous preterm birth

AIMS

This study compared the effectiveness and safety of cervical cerclage combined with cervical pessary in the treatment of cervical incompetence and that of cervical cerclage alone and cervical pessary alone.

METHODS

We performed a prospective cohort study of women with cervical incontinence. Subjects were randomized into three groups: cerclage, pessary, and cerclage and pessary combined.

RESULTS

A total of 75 patients with cervical incompetence were enrolled: 37.3% patients had a cervical length <15 mm, and 62.5% had a cervical length of 15-25 mm. Patients with increased body mass index were significantly likely to have a short cervix (p = .06); patients with a short cervix had earlier rupture of the membrane. The cerclage and pessary groups had more spontaneous abortions than the combined treatment group, which had no abortions or premature births. The mean gestational ages at delivery for the cerclage group (37.82 weeks) and the pessary group (35.73 weeks) were smaller than for the combined treatment group (38.33 weeks). The premature rupture of membranes that was correlated with cervical length had a higher incidence in the pessary group (26.9%).

CONCLUSION

Placement of a cervical cerclage combined with a cervical pessary is a safe technique and has a high success rate in the treatment of cervical incompetence.

Evaluation of additive effect of quantitative fetal fibronectin to cervical length for prediction of spontaneous preterm birth among asymptomatic high-risk women

Objective: To determine if quantitative fetal fibronectin (qFFN) in addition to transvaginal ultrasound (TVU) cervical length (CL) measurement between 18^0/7 and 23^6/7 weeks would be predictive of spontaneous preterm birth (sPTB) at <35^0/7 weeks among asymptomatic high-risk women as defined by those with prior sPTB > 20^0/7 weeks.Material and methods: A prospective observational study of asymptomatic women with singleton gestations between 18^0/7 and 23^6/7weeks and one or more prior SPTB was performed. Women at their anatomy scan who opted into universal CL screening were enrolled. At enrollment, a vaginal speculum exam was performed to collect cervico-vaginal fluid from the posterior fornix using fetal fibronectin (FFN) swab. These women were then followed until delivery. Women with multiple gestations, rupture of membranes, vaginal bleeding, intercourse, or vaginal exam within 48 h of enrollment were excluded. Physicians were blinded to the qFFN levels, but the CL measurements were made available. The primary outcome was sPTB < 35^0/7 weeks.Results: Of the 105 asymptomatic women with prior sPTB who were prospectively enrolled, 19 (18.1%) had recurrent sPTB < 37^0/7 weeks. None of the sPTB were iatrogenic. Using receiver-operating characteristic curves, qFFN ≥ 10 ng/mL had the highest sensitivity with subsequent lowest false negative rate, while FFN ≥ 50 ng/mL was identified as being the best balance of sensitivity and false positive rate for predicting sPTB < 35^0/7 weeks. As compared with CL ≤ 25 mm alone, with the use of CL ≤ 25 mm or qFFN ≥ 50 ng/mL as screening criteria for prediction of SPTB < 35^0/7 weeks, sensitivity improved from 18.2 to 63.6%, specificity decreased from 96.8 to 82.1%, positive predictive value (PPV) decreased from 40.0 to 29.2%, negative predictive value (NPV) marginally improved from 91.1 to 95.1%.Conclusion: In women with singleton gestations with prior SPTB, qFFN can be used as an adjunct to triage patients who are found to have a shortened cervix. Sensitivity and NPVs improved with the addition of qFFN to TVU CL screening alone in women with singleton gestations with prior SPTB. However, specificity and PPVs decreased.

Co-morbidity of cervical incompetence with polycystic ovarian syndrome (PCOS) negatively impacts prognosis: A retrospective analysis of 178 patients

Background

Cervical incompetence is an important cause of miscarriage and premature birth and polycystic ovary syndrome is a heterogeneous endocrine disorder that is the most common cause of anovulatory infertility and eugonadotrophic hypogonadism. By now, it is still debated whether women with PCOS have an increased risk of miscarriage and there have been no studies about the pregnancy outcomes of cervical incompetence patients with PCOS.

Methods

The following clinical data of cervical incompetence patients with/without PCOS who were treated between September 2006 and September 2013 were retrospectively analysed: onset gestational age, termination gestational age, pregnancy outcome, co-morbid insulin resistance (IR) in PCOS patients, the influence of IR, co-morbid hyperandrogenism (HA) in PCOS patients, and the influence of HA. The independent samples t-test and chi-square trend test were used to analyse the data.

Results

A total of 178 singleton pregnancy cases with cervical incompetence were identified. The average onset gestational age was 23.9 ± 4.3 weeks, and the average termination gestational age was 32.5 ± 5.5 weeks. Of these 178 singleton pregnancy cases, 40 (22.5 %) ended in miscarriage, 82 (46.1 %) ended in preterm birth, and 56 (31.5 %) ended in term birth. Eighty cases (44.9 %) exhibited PCOS co-morbidity, and those cases had an average onset gestational age of 22.3 ± 3.8 weeks and an average termination gestational age of 31.2 ± 5.7 weeks, which were both significantly different from those of the non-PCOS group (both P < 0.001). Compared with the non-PCOS group (15.3 % miscarriage, 48.0 % preterm birth, and 36.7 % term birth), the PCOS group exhibited worse pregnancy outcomes (31.3 % miscarriage, 43.8 % preterm birth, and 25 % term birth) (P = 0.01). Among the 80 PCOS patients, 45 (56.3 %) exhibited co-morbid IR, and the IR group exhibited significantly worse pregnancy outcomes than the non-IR group (P = 0.03). Among the 80 PCOS patients, 54 cases (67.5 %) exhibited co-morbid HA, and there was no statistical difference on the pregnancy outcomes between the two groups. The multivariate logistic regression model revealed that PCOS was significantly correlated with miscarriage (OR: 3.72, 95 % CI: 1.37–10.13).

Conclusions

The cervical incompetence patients with co-morbid PCOS exhibited earlier onset gestational ages, earlier termination gestational ages and worse pregnancy outcomes. For patients with co-morbid insulin resistance, the pregnancy outcomes were worse than expected.

Evaluation of the ability of cervical length and fetal fibronectin measurement to predict preterm delivery in asymptomatic women with risk factors

OBJECTIVE

To evaluate the power of transvaginal ultrasound cervical length (CL) and fetal fibronectin (fFN) measurement for the prediction of preterm delivery (PTD) in asymptomatic women with risk factors.

METHODS

Between January 2010 and October 2012, 218 women with singleton pregnancies and a high risk for PTD (i.e. prior history of PTD, cervical surgeries, late miscarriages, uterine abnormalities or premature rupture of the membranes) were selected. CL was measured by transvaginal ultrasonography between 14 and 22 weeks, and a CL<2.5 cm was considered to be short. The fFN was measured with a sterile speculum examination. The primary outcome was the spontaneous PTD rate at <34(+0) and <37(+0) weeks, and the PTD rate was analyzed by either of two methods alone or combined.

RESULTS

There were 213 cases included in the analysis, and 47 women (22.1%) had positive fFN. The average CL of women with positive fFN (2.3 ± 0.9 cm) was significantly shorter than that of women with negative fFN (3.1 ± 0.8 cm; p=0.02). There were 25 (11.7%) and 38 (18.8%) cases with PTD at <34(+0) and <37(+0) weeks, respectively. By individual analyses, the highest PTD rate was 51.2% in women with positive fFN at <37(+0) weeks. The sensitivity and diagnostic efficiency values for PTD prediction by CL were low at <34(+0) and <37(+0) weeks. The values of diagnostic efficiency by fFN were >80% at <34(+0) and <37(+0) weeks. In the combined analysis, the highest PTD rate was 57.1% in women with CL ≤ 2.5 cm and positive fFN at <37(+0) weeks. The Kaplan-Meier curve indicated that there were significant differences among the four groups (χ(2)=54.261; p=0.000).

CONCLUSIONS

These results indicate a significant correlation between fFN and PTD prediction. The PTD prediction could be enhanced by combined CL and fFN measurement.

Cervical length for predicting preterm birth and a comparison of ultrasonic measurement techniques

Introduction: Preterm birth is the leading cause of neonatal morbidity and mortality not attributable to congenital anomalies or aneuploidy. It has been shown that a shortened cervix is a powerful indicator of preterm births in women with singleton and twin gestations - the shorter the cervical length, the higher the risk of spontaneous preterm birth. Ultrasound measurements of the cervix are a more accurate way of determining cervical length (CL) than using a digital method. Background: There are three approaches that may be used to perform ultrasound measurements of the cervix; these are the transabdominal (TA), transperineal (TP) and the transvaginal (TV) approach. The TV approach is considered to be the gold standard. In women who are considered to be at a high risk of preterm birth it is now recommended that the cervix is measured at the mid-trimester ultrasound using the TV ultrasound approach. For women considered to be at a historical low risk the TV scan is not recommended, however it has been found that many women who deliver a preterm baby have no known risk factors. Conclusion: There is contradictory evidence in the literature with regard to the correlation between TA, TP and TV measurements. This article provides an overview of these three approaches with a focus on the clinical value for the assessment of the maternal cervix.