Cerclage for Short Cervix on Ultrasonography in Women With Singleton Gestations and Previous Preterm Birth: A Meta-Analysis

Cervical elastography using E-Cervix™ for prediction of preterm birth in twin pregnancies with threatened preterm labor

OBJECTIVE

To evaluate the prediction performance of E-Cervix™ for preterm birth in twin pregnancies with threatened preterm labor.

METHODS

This was a single-center retrospective cohort study of twin pregnancies presenting to obstetrics triage for threatened preterm labor (PTL) between 23 0/7 - 33 6/7 weeks who received screening for PTL with transvaginal ultrasound cervical length (TVU CL) and cervical elastography with E-Cervix™ at the time of triage. Cervical elastography parameters were examined and compared between women who delivered preterm and those who did not. The quantification of cervical strain was calculated by a data analysis system that directly analyzes raw data from the region of interest (ROI) and described as hardness ratio (HR), mean strain level within 1 cm from internal (IOS) and external (EOS) os.

RESULTS

63 twin gestations without prior preterm birth and with threatened PTL between 23 0/7 - 33 6/7 weeks of gestation were included in the study. 27 (42.9 %) had cervical length < 25 mm, and were admitted for true PLT. Out of the 36 women with cervical length ≥ 25 mm, 6 (16.7 %) were admitted. Women with threatened PTL had significantly higher HR compared to those with true PTL (p < 0.01), and significantly lower IOS and EOS. Women who delivered preterm had significantly higher HR compared to those who did not delivery preterm and significantly lower IOS and EOS, in overall cohort, and in the subset of women with true PTL. Incidences of HR < 50 % and < 35 % were statistically significantly higher in women who delivered preterm compared to those who did not (p < 0.01).

CONCLUSION

Cervical elastography with E-Cervix™ may be useful for assessment of twin gestations presenting to obstetrics triage for threatened PTL.

Preterm birth in low-middle income Countries

Preterm birth (PTB), remains a major cause of significant morbidity and mortality world-wide with about 12-15million preterm births occurring every year. Although the overall trend is decreasing, this is mainly in high-income countries (HIC). The rate remains high in low-and middle-income countries (LMIC) varying on average between 10 and 12% compared to 9% in HIC. The pathogenesis of PTB is complex and multifactorial. Attempts to reduce rates that have focused on PTB as a single condition have in general been unsuccessful. However, more recent attempts to phenotype PTB have resulted in targeted preventative approaches which are yielding better results. Prevention (primary or secondary) is the only approach that has been shown to make a difference to rates of PTB. These include identifying risk factors pre-pregnancy and during pregnancy and instituting appropriate measures to address these. In LMIC, although some approaches that have been shown to be effective in some HIC are adaptable, there is a need to involve stakeholders at all levels in utilizing evidence preferrably generated in LMIC to implement strategies that are likely to reduce the rate of PTB. In this review, we focus on prevention and how to involve policy makers in the process of applying evidence into policy that would reduce PTB in LMIC.

Racial and Ethnic Disparities in Cervical Insufficiency, Cervical Cerclage, and Preterm Birth

Background: The frequency of cervical insufficiency differs among the major racial and ethnic groups, with limited data specific to Asian American and Native Hawaiian/Pacific Islander (AANHPI) subpopulations. We assessed cervical insufficiency diagnoses and related outcomes across 10 racial and ethnic groups, including disaggregated AANHPI subgroups, in a large population-based cohort. Study Design: We performed a retrospective cohort study of all singleton births between 20-42 weeks' gestation in California from 2007 to 2018. Logistic regression models were performed to estimate the odds of cervical insufficiency and, among people with cervical insufficiency, the odds of cerclage and preterm birth according to self-reported race and ethnicity. Results: Among 5,114,470 births, 38,605 (0.8%) had a diagnosis code for cervical insufficiency. Compared with non-Hispanic White people, non-Hispanic Black people had the highest odds of cervical insufficiency (adjusted odds ratio [aOR] 3.07; 95% confidence interval [CI], 2.97, 3.18), for cerclage placement and higher odds for preterm birth. Disaggregating AANHPI subgroups showed that Indian people had the highest odds (aOR 1.94; 95% CI, 1.82, 2.07) of cervical insufficiency and had significantly higher odds of cerclage without increased odds of preterm birth; Southeast Asian people had the highest odds of preterm birth. Conclusion: Within a large, diverse population-based cohort, non-Hispanic Black people experienced the highest rates of cervical insufficiency, and among those with cervical insufficiency, had among the highest rates of cerclage and preterm birth. Among AANHPI subgroups specifically, Indian people had the highest rates of cervical insufficiency and cerclage placement, without increased rates of preterm birth; Southeast Asian people had the highest rates of preterm birth, without increased rates of cerclage. Disaggregating AANHPI subgroups identifies important differences in obstetric risk factors and outcomes.

Diabetes Mellitus as a Risk Factor for Spontaneous Preterm Birth in Women with a Short Cervix after Ultrasound-Indicated Cerclage

Background: Preterm birth (PTB) is a significant challenge in contemporary obstetrics, affecting over one in ten infants worldwide and accounting for 75% of perinatal mortality. Short cervical length during mid-trimester is well known to be associated with an increased risk of spontaneous preterm birth (sPTB). Ultrasound-indicated cerclage (UIC) is recommended to prevent sPTB in women with a short cervix at mid-trimester and a history of sPTB. Objectives: This retrospective observational study aimed to examine the impact of diabetes and obesity on the occurrence of sPTB in women who underwent UIC due to mid-trimester cervical shortening. Methods/Results: The analysis revealed that cervical length at the time of operation, preoperative erythrocyte sedimentation rate levels, and diabetes were independent risk factors for sPTB. Additionally, the presence of diabetes, particularly when combined with obesity, significantly elevated the risk of sPTB. Women with pregestational diabetes or those requiring insulin treatment had a higher propensity for preterm delivery compared to those with gestational diabetes managed through diet control alone. Conclusions: These findings emphasize the importance of considering maternal metabolic factors, such as diabetes and obesity, in women with a short cervix when planning for UIC and highlight the crucial role of optimizing maternal glucose control and weight management in reducing the risk of sPTB.

Antenatal reproductive screening for pregnant people including preconception: Provides the best reproductive opportunity for informed consent, quality, and safety

INTRODUCTION

This antenatal screening review will include reproductive screening evidence and approaches for pre-conception and post-conception, using first to third trimester screening opportunities.

METHODS

Focused antenatal screening peer-reviewed publications were evaluated and summarized.

RESULTS

Evidenced-based reproductive antenatal screening elements should be offered and discussed, with the pregnancy planning or pregnant person, during Preconception (genetic carrier screening for reproductive partners, personal and family (including reproductive partner) history review for increased genetic and pregnancy morbidity risks); First Trimester (fetal dating with ultrasound; fetal aneuploidy screening plus consideration for expanded fetal morbidity criteria, if appropriate; pregnant person preeclampsia screening; early fetal anatomy screening; early fetal cardiac screening); Second Trimester for standard fetal anatomy screening (18-22 weeks) including cardiac; pregnant person placental and cord pathology screening; pregnant person preterm birth screening with cervical length measurement); Third Trimester (fetal growth surveillance; continued preterm birth risk surveillance).

CONCLUSION

Antenatal reproductive screening has multiple elements, is complex, is time-consuming, and requires the use of pre- and post-testing counselling for most screening elements. The use of preconception and trimesters 'one to three' requires clear patient understanding and buy-in. Informed consent and knowledge transfer is a main goal for antenatal reproductive screening approaches.

Screening for women at risk of spontaneous preterm birth, including cervical incompetence

Preterm births remain one of the biggest challenges in obstetrics worldwide. With the advancement of neonatal care, more premature neonates survive with long term consequences. Therefore, preventing or delaying preterm births starting from the preconceptional or antenatal periods are important. Among the numerous screening strategies described, not one can fit into all. Nonetheless, approaches including identifying women with modifiable risk factors for preterm births, genitourinary infections and short cervical length are the most useful. In this article, the current evidence is summarized and the best strategies for common clinical scenerios including cervical incompetence, history of second trimester loss or early preterm births, incidental short cervix and multiple pregnancy are discussed.

A comparison of Mersilene tape versus braided suture in transvaginal cervical cerclage: A retrospective case-control study

OBJECTIVE

Previous studies have indicated that there is an association between cervical cerclage and type of suture material. However, it is still unclear which suture material can provide the greatest benefit to patients who have undergone cerclage. This study investigated the effect of two different suture materials (Mersilene tape vs braided suture) used for transvaginal cervical cerclage placement on maternal outcomes of women with cervical insufficiency.

METHODS

In this retrospective case-control study, 170 women who underwent history-, ultrasound-, or physical examination-indicated transvaginal cervical cerclage were categorized according to suture materials used for cerclage: a total of 96 received Mersilene tape and 74 received braided suture. Study participants received a transvaginal cervical cerclage before 28 weeks and were followed up until delivery to assess pregnancy and neonatal outcomes. The primary outcome was gestational age at delivery. Secondary outcomes included preterm premature rupture of membranes (PPROM), premature rupture of membranes (PROM), chorioamnionitis, neonatal survival rate, and neonatal morbidity.

RESULTS

Out of 170 eligible women, 74 (43.5%) received braided suture while 96 (56.5%) received Mersilene tape. Baseline characteristics were similar between the two groups. The group that received braided suture had a lower incidence of gestational age at delivery <37 weeks (29.2% vs 54.2%, P = 0.046), PPROM (9.5% vs 21.9%, P = 0.029) and PROM (17.6% vs 32.3%, P = 0.028) compared to the group that received Mersilene tape. However, there were no significant differences between the two groups in average gestational age at delivery, the rate of gestational age at delivery <24, <28, <32, and < 34 weeks, chorioamnionitis, and neonatal survival rate, as well as neonatal morbidity.

CONCLUSION

Compared to Mersilene tape, the utilization of braided suture has been significantly associated with a reduction in the incidence of gestational age at delivery <37 weeks, as well as a decreased risk of PPROM and PROM. However, the use of braided sutures did not result in discernible differences in the rates of chorioamnionitis or adverse neonatal outcomes.

Cerclage prevents ascending intrauterine infection in pregnant mice

BACKGROUND

The treatment for cervical insufficiency is cerclage surgery. Although cerclage is a common therapy for prevention of preterm birth, there is no consensus about its mechanism of efficacy. Previous investigators have hypothesized that cerclage prevents preterm birth by improving the cervical barrier to ascending infection. However, this hypothesis is difficult to study in human pregnancy.

OBJECTIVE

In a mouse model of ascending infection, we hypothesized that a cerclage improves the cervical barrier leading to decreased ascending intrauterine infection and inflammation. An abdominal cerclage was studied because a vaginal cerclage is not feasible in mice.

STUDY DESIGN

To perform an abdominal cerclage, laparotomy was performed on timed, pregnant C57BL/6 mice on gestational day 10 (E10). A 6-0 silk suture was placed around the cervix just below the junction of the 2 uterine horns. Sham controls received the same surgery, but no cerclage was placed. To track ascending infection nonpathogenic E coli K12 was genetically modified to express bioluminescence. On E15, bioluminescent E coli K12 (20 μL of 1×109 bacteria) was inoculated into the vagina. Whole-body bioluminescence imaging was performed 0.5 hours and 24 hours after inoculation. To assess intrauterine inflammation, pathogenic E coli K1 was used. On E15, bacterial inoculums of E coli K1 (20 μL of 1×104 bacteria) were vaginally administered. Samples of uterus, placenta, and fetal membranes were collected 24 hours after inoculation. Gene expression of inflammation-related proteins was compared between 3 groups: (1) sham control surgery + inoculation of phosphate-buffered saline (PBS), (2) sham control surgery + inoculation of E coli K1, and (3) cerclage surgery + inoculation of E coli K1.

RESULTS

Abdominal cerclage was well tolerated. No cases of preterm birth were seen following abdominal cerclage. Whole-body bioluminescent imaging performed 0.5 hours post inoculation showed a strong luminescence signal in the vaginal region of mice in both control and experimental groups indicating successful bacteria inoculation. Twenty-four hours after inoculation, bioluminescent signal was seen ascending into the uterine horns in all control mice. However, in mice with abdominal cerclages, no bioluminescent signal was seen after 24 hours. When the reproductive tissues were imaged separately in control mice, strong bioluminescence signal was detected in the placenta, fetal membranes, and uterus. Gene expression studies showed that cerclage significantly decreased the expression of inflammatory proteins induced by E coli K1 in the uterus, placenta, and fetal membranes.

CONCLUSION

In this mouse model of ascending intrauterine infection, abdominal cerclage prevented ascending infection of E coli. In addition, abdominal cerclage prevented expression of inflammatory cytokines in the uterus, placenta, and membranes of mice. The study provides evidence for a potential mechanism of cerclage success in human pregnancy.

Validating staging criteria for sonographic and physical examination for cervical changes at <24 weeks' gestation to predict preterm birth

BACKGROUND

Preterm birth represents a significant clinical challenge, and the ability to predict it effectively is a priority in obstetrics. The cervix undergoes specific changes during pregnancy, and staging these changes may offer a valuable predictive model for preterm birth, particularly among women with a midtrimester short cervical length.

OBJECTIVE

The study aimed to validate a proposed staging model for asymptomatic women with midtrimester short cervical length and to evaluate its potential for predicting preterm birth. The integration of cervical examination and inspection with cervical length measurement was a novel approach to be assessed.

STUDY DESIGN

This was a multicenter, retrospective cohort study that included 925 pregnant women with a singleton fetus and a midtrimester cervical length measurement of ≤25 mm. Cervical conditions were assessed using ultrasonography, a speculum, and a physical examination and were classified into 1 of 5 cervical stages to correlate with the likelihood of preterm birth. Statistical analyses included Kaplan-Meier survival analysis to illustrate the time-to-event characteristics across the 5 stages and density plot evaluation to visualize the distribution of the gestational ages within the stages.

RESULTS

The staging model included 5 stages based on cervical length, appearance, and dilatation. Among the 925 participants, 649 were classified as being stage 1, 245 as stage 2, 18 as stage 3, 10 as stage 4, and 3 as stage 5. The observed rates of preterm birth before 37 weeks for individuals classified in stages 1, 2, 3, 4, and 5 were 22.3%, 26.5%, 44.4%, 60%, and 66.7%, respectively (P=.005). The overall observed rates of preterm birth before 28, 32, 34, and 37 weeks' gestation were 5.5%, 9.9%, 12.2%, and 24.1%, respectively (P=.005).

CONCLUSION

This study validated the proposed staging criteria as an effective predictor of preterm birth caused by cervical insufficiency. The results demonstrate a significant increase in the preterm birth rate with advancing stage classification, indicating that the staging effectively stratified women based on their risk for preterm birth and highlighting the potential use for targeted interventions. Implementing these staging criteria can potentially improve the counseling and management of pregnant women at risk for preterm birth.

Contractions of the lower uterine segment during transvaginal ultrasound cervical length: incidence, significance, proper measurement, and management

An accurate transvaginal ultrasound cervical length is paramount to obtain the best prediction for preterm birth. Transvaginal ultrasound cervical length should be optimally obtained when a lower uterine segment contraction is not seen. For universal transvaginal ultrasound cervical length screening at approximately 20 weeks of gestation, the options are to do the transvaginal ultrasound soon after bladder void (lower uterine segment contractions present in 16%-43% of this approach) or to wait until the end of the anatomy scan (ideally within 30 minutes after bladder voiding) to decrease the chance of a lower uterine segment contraction. If the lower uterine segment contraction persists even after waiting up to 20 minutes or more, only the true transvaginal ultrasound cervical length should be reported. In particular, in patients with a previous spontaneous preterm birth, if the lower uterine segment contraction persists, the transvaginal ultrasound cervical length can be repeated in ≤7 days even in the presence of a normal (>25 mm) cervical length. Similar to a blood pressure cuff that must be of the right size for proper blood pressure measurement and a glucometer that must be properly calibrated, screening with transvaginal ultrasound cervical length should only be performed following a proper and standardized technique, including avoiding as much as feasible the presence of lower uterine segment contractions.

Randomized trial of screening for preterm birth in low-risk women - the preterm birth screening study

BACKGROUND

Preterm birth is a major cause of perinatal morbidity and mortality. It is unclear whether the introduction of a universal transvaginal ultrasound cervical length screening program in women at low risk for preterm delivery is associated with a reduction in the frequency of preterm birth.

OBJECTIVE

To test the hypothesis that the introduction of a midtrimester universal transvaginal ultrasound cervical length screening program in asymptomatic singleton pregnancies without prior preterm delivery would reduce the rate of preterm birth at <37 weeks of gestation.

STUDY DESIGN

This study was a multicenter nonblinded randomized trial of screening of asymptomatic singleton pregnancies without prior spontaneous preterm birth, who were randomized to either cervical length screening program (ie, intervention group) or no screening (ie, control group). Participants were randomized at the time of their routine anatomy scan between 18 0/7 and 23 6/7 weeks of gestation. Women randomized in the screening group received cervical length measurement. Those who were found to have cervical length ≤25 mm were offered 200 mg vaginal progesterone daily along with cervical pessary. The primary outcome was preterm birth at <37 weeks. The risk of primary outcome was quantified by the relative risk with 95% confidence interval, and was based on the intention-to-screen principle.

RESULTS

A total of 1334 asymptomatic women with singleton pregnancies and without prior preterm birth, were included in the trial. Out of the 675 women randomized in the transvaginal ultrasound cervical length screening group, 13 (1.9%) were found to have transvaginal ultrasound cervical length ≤25 mm during the screening. Preterm birth at <37 weeks of gestation occurred in 48 women in the transvaginal ultrasound cervical length screening group (7.5%), and 54 women in the control group (8.7%) (relative risk, 0.86; 95% confidence interval, 0.59-1.25). Women randomized in the transvaginal ultrasound cervical length screening group had no significant differences in the incidence of preterm birth at less than 34, 32, 30, 28, and 24 weeks of gestation.

CONCLUSION

The introduction of a universal transvaginal ultrasound cervical length screening program at 18 0/6 to 23 6/7 weeks of gestation in singleton pregnancies without prior spontaneous preterm birth, with treatment for those with cervical length ≤25 mm, did not result in significant lower incidence of preterm delivery than the incidence without the screening program.

Effect of different surgical routes on pregnancy outcome of history-indicated cervical cerclage

OBJECTIVE

To study the guiding significance of medical history on laparoscopic and vaginal cervical cerclage in the treatment of cervical incompetence and its influence on pregnancy outcome.

METHODS

A total of 53 cases by laparoscopic abdominal cervical cerclage (LAC group) before pregnancy and 73 cases by transvaginal cervix cerclage (TVC group) at 12-14 weeks of pregnancy were collected. Multivariate logistic regression analysis was performed on the influencing factors of delivery gestational weeks. Furthermore, the gestational weeks after cervical cerclage were compared between the two groups with high- and low-risk grades.

RESULTS

The number of previous uterine cavity operations in LAC group was more than that TVC group, and the costs of operation were more than TVC group. At the same time, the hospitalization days and operation time were longer than those in TVC group, and the delivery rate of cesarean section was higher than TVC group, but the total hospitalization times were less than TVC group (P < 0.05). The rate of delivery before 34 weeks of pregnancy and the incidence of premature rupture of membranes or premature labor in LAC group were lower than those in TVC group (P < 0.05). In TVC group, the increased number of prior PTB or STL and the history of cervical cerclage failure would increase the risk of premature delivery before 34 weeks of pregnancy. There was no increased risk of preterm delivery before 34 weeks of pregnancy in LAC group (P > 0.05). According to the risk level, in the high-risk group, the delivery rate of LAC group at gestational weeks < 37 weeks, < 34 weeks and < 28 weeks was lower than that of TVC group.

CONCLUSION

Laparoscopic cervical cerclage might be more effective in preventing premature delivery before 34 weeks of gestation, and its influence on delivery gestational weeks was not affected by related medical history. For high-risk patients with the history of prior PTB or STL and failed cerclage, laparoscopic cervical cerclage might be more effective than vaginal cervical cerclage in preventing extremely preterm before 28 weeks, premature delivery before 34 weeks and premature delivery before 37 weeks. Therefore, our limited experience suggested that LAC can be a recommended option for patients with high-risk history.

Risk factors for high-stage histological chorioamnionitis among pregnancies with cervical incompetence

AIM

The study aimed to identify predictive risk factor to identify high-stage histological chorioamnionitis (HCA) in pregnancies with cervical incompetence (CIC).

METHODS

A retrospective cohort study was conducted by including 116 pregnant women with cervical incompetence that required prophylactical and therapeutical cerclage. The histopathology examination on placenta was conducted with informed patient consent. All the cases included in this study were divided based on the severity degree of HCA. The demographic characteristic and the parameters related to maternal and fetal outcome were all analyzed. Besides, perioperative parameters of cerclage, including cervical length, cervical morphology, and laboratory indexes were also compared between two groups. Univariate and multivariate logistic regression analysis were used to determine the risk factor of severe chorioamnionitis.

RESULTS

Severe HCA was significantly associated with cervical morphology, cerclage indication, cerclage type, and cervical length measured via ultrasound and vaginal examination. After adjusted for confounders, V-type funneling and short cervix was indicated as independent risk factors of severe HCA by multivariate logistic regression analysis, respectively.

CONCLUSIONS

V-type funneling and short cervix may indicate the elevated risk of high-stage HCA. Due to the negative outcomes related with high-stage HCA, appropriate prenatal treatment would improve the pregnancy outcomes in cerclaged population. To facilitate postpartum treatment, placental histological examination should be routinely recommended to identify the high-stage HCA, especially in high risk pregnancies.

Emergency Cesarean Section in a Dichorionic Diamniotic Twin Pregnancy With Hydrops Fetalis: A Report of a Critical Case

This case report describes the emergent scenario of a 41-year-old primipara at 31.2 weeks of gestation, presenting with abdominal and back pain in the context of a dichorionic diamniotic twin pregnancy complicated by hydrops fetalis. The patient, with a history of hypertension, hyperthyroidism, and a cervical stitch in place, underwent an emergency lower segment cesarean section. The ultrasound revealed an intrauterine left footling in one twin, contributing to the suspected hydrops fetalis. Neonatal complications arose, particularly with Baby B, necessitating immediate resuscitation and intensive care. Successful outcomes were achieved through a well-coordinated multidisciplinary approach involving obstetricians, neonatologists, and anesthesiologists. This case underscores the importance of prompt recognition, timely interventions, and collaborative care in managing complex pregnancies, shedding light on the challenges associated with dichorionic diamniotic twin pregnancies and emphasizing the need for ongoing research to refine perinatal strategies.

Cervical assessment certification and its impact on performance quality in the context of universal cervical screening

OBJECTIVE

To assess the impact of the introduction of universal transvaginal cervical screening and certification on the quality of cervical length ultrasound images.

METHODS

The present study included a retrospective cohort of singleton pregnancies that underwent transvaginal cervical length measurement at the anatomical scan (180/7 and 236/7 weeks) before (period A, 2015-2017) and after (period B, 2017-2019) the introduction of universal transvaginal cervical length screening. Independent observers blindly evaluated the images obtained for cervical length using a qualitative scoring method based on five criteria, according to the Fetal Medicine Foundation.

RESULTS

In all, 6013 patients met the inclusion criteria, 3333 in period A and 2680 in period B. Maternal characteristics and risk factors for preterm birth were similar between the two periods. The acceptance of transvaginal cervical length measurement in period B was 95.5% in the overall cohort and 100% in the subgroup of high-risk patients. The quality score was significantly higher in period B than in period A. Among the image quality criteria, the anterior/posterior ratio, the correct magnification of the images, and the calipers' placement contributed significantly to the improved quality score in period B. Most of the sonographers performed better in period B, irrespective of the years of experience, but certificate holders obtained higher scores than non-certified sonographers, particularly those in mid-career. The identification of short cervix was significantly higher in period B than in period A.

CONCLUSION

The implementation of universal transvaginal cervical length screening and the certification process are associated with improved quality of cervical length images, even among expert sonographers and in the presence of anatomical pitfalls.

The effectiveness of cervical cerclage in twin pregnancies with a mid-trimester short cervix: A retrospective cohort study

OBJECTIVE

To analyze the effectiveness of cerclage in twin pregnancies with a short cervix.

STUDY DESIGN

Retrospective cohort study performed in two University Institutions in Valencia (Spain) with two different protocols for the management of asymptomatic dichorionic diamniotic twin pregnancies with mid-trimester cervical length ≤ 25 mm: treatment with indomethacin, antibiotics and cerclage (cerclage group) (N = 43) versus expectant management (control group) (N = 37).

RESULTS

The initial cervical length was similar in both groups but detection of a short cervix was performed earlier in the cerclage group (21.6 vs 24.1 weeks, p < 0.001). Women with cerclage had a greater pregnancy latency (12.5 vs. 7.7 weeks, p < 0.001); higher gestational age at delivery (34.1 vs. 31.8 weeks, p < 0.04); less spontaneous preterm birth (SPB) < 28 weeks (11.6 % vs 37.8 %, p < 0.009); higher birthweight (2145 vs 1733 g, p < 0.001); lower birthweight < 1500 g (12.5 % vs 40.0 %, p < 0.001); less admissions to the neonatal intensive care unit (NICU) (24.1 % vs 43.3 %, p < 0.03); shorter stay at NICU (25.6 vs 49.4 days, p < 0.02); lower respiratory distress requiring mechanical ventilation (14.9 % vs 36.5 %, p < 0.02); fewer patent ductus arteriosus (8.9 % vs 26.9 %, p < 0.008); and lower composite adverse neonatal outcome (26.6 % vs. 44.8 %, p < 0.03). Cerclage and gestational age at diagnosis were the only independent predictors of SPB < 32 and < 28 weeks by multivariate analysis. The cumulative data in the literature show promising beneficial effects of cerclage.

CONCLUSION

Our data suggest that cerclage in asymptomatic twin pregnancies with a short cervix may reduce the earliest SPB and may improve neonatal outcome.

Prevention of spontaneous preterm delivery – an update on where we are today

Spontaneous preterm birth (delivery before 37 completed weeks) is the single most important cause of perinatal morbidity and mortality. The rate is increasing world-wide with a great disparity between low, middle and high income countries. It has been estimated that the cost of neonatal care for preterm babies is more than 4 times that of a term neonate admitted into the neonatal care. Furthermore, there are high costs associated with long-term morbidity in those who survive the neonatal period. Interventions to stop delivery once preterm labor starts are largely ineffective hence the best approach to reducing the rate and consequences is prevention. This is either primary (reducing or minimizing factors associated with preterm birth prior to and during pregnancy) or secondary - identification and amelioration (if possible) of factors in pregnancy that are associated with preterm labor. In the first category are optimizing maternal weight, promoting healthy nutrition, smoking cessation, birth spacing, avoidance of adolescent pregnancies and screening for and controlling various medical disorders as well as infections prior to pregnancy. Strategies in pregnancy, include early booking for prenatal care, screening and managing medical disorders and their complications, and identifying predisposing factors to preterm labor such as shortening of the cervix and timely instituting progesterone prophylaxis or cervical cerclage where appropriate. The use of biomarkers such as oncofetal fibronectin, placental alpha-macroglobulin-1 and IGFBP-1 where cervical screening is not available or to diagnosis PPROM would identify those that require close monitoring and allow the institution of antibiotics especially where infection is considered a predisposing factor. Irrespective of the approach to prevention, timing the administration of corticosteroids and where necessary tocolysis and magnesium sulfate are associated with an improved outcome. The role of genetics, infections and probiotics and how these emerging dimensions help in the diagnosis of preterm birth and consequently prevention are exciting and hopefully may identify sub-populations for targeted strategies.

Factors Associated with Spontaneous Preterm Birth after Ultrasound-Indicated Cerclage

Ultrasound-indicated cerclage (UIC) is recommended to prevent spontaneous preterm birth (sPTB) in women with a short cervix at mid-trimester and a history of PTB. We assessed the factors related to sPTB after UIC and determined the corresponding risks. This retrospective cohort study was conducted at a university hospital. UIC was performed between 15 and 26 weeks of gestation in women with a cervical length of <2.5 cm. Univariate and multivariate analyses were used to examine factors associated with sPTB after UIC. An earlier gestational age and shorter cervical length at UIC were associated with sPTB after UIC. While PTB history was not associated with an increased risk of sPTB, it did increase the risk of repeat cerclage after UIC. Higher levels of preoperative serum inflammatory markers and obesity significantly increased the risk of sPTB after UIC. These findings provide helpful guidance for patient counseling and management in predicting the delivery timing after UIC in women with a short cervix in the mid-trimester.

Maternal and obstetrical factors associated with short cervical length at midtrimester in women with no history of preterm delivery

AIM

To evaluate associations between maternal characteristics and a short cervix in patients without history of preterm delivery, and to determine if these characteristics can predict the presence of a short cervix.

MATERIALS AND METHODS

This is a retrospective cohort study that included 18,592 women with singleton pregnancies without history of previous preterm deliveries who underwent universal transvaginal cervical length (TVCL) screening between 18 + 0 and 23 + 6 weeks/days of gestation. A short cervix was defined as a cervical length (CL) ≤25 mm, ≤20 mm, and ≤15 mm. Associations between maternal age, weight, height, body mass index (BMI), previous term deliveries, and history of previous miscarriages, with a short cervix were evaluated using logistic regression models.

RESULTS

The prevalence of a short cervix in our population was: CL ≤25 mm, 2.2% (n = 403); CL ≤20 mm, 1.2% (n = 224); and CL ≤15 mm, 0.9% (n = 161). Women with BMI >30 and/or previous abortions constituted 45.5% of the total population (8463/18,582). Significant associations with short cervix were observed for women with BMI ≥30, and for women with at least one previous abortion (p < .001). Parous women had a significantly lower association with a short cervix than nulliparous women (p < .001). Maternal age or height were not associated with a short cervix. Prediction of short cervix based on presence of any of the following: BMI ≥ 30 or previous abortions showed sensitivities of 55.8% (≤25 mm), 61.6% (≤20 mm), and 63.4% (≤15 mm) with similar specificity (50.1-54.6%) and likelihood ratio positive (1.2-1.5); and prediction based on BMI ≥ 30 and previous abortions showed sensitivities of 11.1% (≤25 mm), 14.7% (≤20 mm), and 16.7% (≤15 mm) with specificity 93%.

CONCLUSIONS

Among low risk women for spontaneous preterm delivery, those with a BMI ≥30 and/or previous miscarriages had a significantly increased risk for a short cervix at 18 + 0 and 23 + 6 weeks/days of gestation. Despite these significant associations, screening by maternal risk factors in a low risk population of pregnant women should not be an alternative to mid-trimester universal CL measurement.

Persistence Pays Off: Live Birth after Uterus Transplant, Overcoming Recurrent Pregnancy Loss with Cerclage Placement

Recipients of uterus transplantation have unique factors that may increase their risk of cervical insufficiency. This report describes a uterus transplant recipient with cervical insufficiency resulting in two second-trimester miscarriages. After McDonald cerclages (one that failed), she underwent an interval transabdominal cerclage and delivered a healthy term child in her third pregnancy. The longitudinal information of this case provides observations from which we can propose testable hypotheses that address venous outflow and inflammation. This case also suggests that there could be a role for prophylactic cerclage placement at the time of transplantation.

Development and validation of a nomogram to predict spontaneous preterm birth in singleton gestation with short cervix and no history of spontaneous preterm birth

Background

Spontaneous preterm birth (sPTB) stands as a leading cause of neonatal mortality. Consequently, preventing sPTB has emerged as a paramount concern in healthcare. Therefore, our study aimed to develop a nomogram, encompassing patient characteristics and cervical elastography, to predict sPTB in singleton pregnancies. Specifically, we targeted those with a short cervix length (CL), no history of sPTB, and who were receiving vaginal progesterone therapy.

Methods

A total of 568 patients were included in this study. Data from 392 patients, collected between January 2016 and October 2019, constituted the training cohort. Meanwhile, records from 176 patients, spanning November 2019 to January 2022, formed the validation cohort. Following the univariate logistic regression analysis, variables exhibiting a P-value less than 0.05 were integrated into a multivariable logistic regression analysis. The primary objective of this subsequent analysis was to identify the independent predictors linked to sPTB in the training cohort. Next, we formulated a nomogram utilizing the identified independent predictors. This tool was designed to estimate the likelihood of sPTB in singleton pregnancies, particularly those with a short CL, devoid of any sPTB history, and undergoing vaginal progesterone therapy. The C-index, Hosmer-Lemeshow (HL) test, calibration curves, decision curve analysis (DCA), and receiver operating characteristic (ROC) were used to validate the performance of the nomogram.

Results

Upon finalizing the univariate analysis, we progressed to a multivariable analysis, integrating 8 variables with P < 0.05 from the univariate analysis. The multivariable analysis identified 7 independent risk factors: maternal age (OR = 1.072; P < 0.001), cervical length (OR = 0.854; P < 0.001), uterine curettage (OR = 7.208; P < 0.001), GDM (OR = 3.570; P = 0.006), HDP (OR = 4.661; P = 0.003), C-reactive protein (OR = 1.138; P < 0.001), and strain of AI (OR = 7.985; P < 0.001). The nomogram, tailored for sPTB prediction, was grounded on these 7 independent predictors. In predicting sPTB, the C-indices manifested as 0.873 (95% CI, 0.827-0.918) for the training cohort and 0.916 (95%CI, 0.870-0.962) for the validation cohorts, underscoring a good discrimination of the model. Additionally, the ROC curves served to evaluate the discrimination of nomogram model across both cohorts. Calibration curves were delineated, revealing no statistically significant differences in both the training (χ2 = 5.355; P = 0.719) and validation (χ2 = 2.708; P = 0.951) cohorts as evidenced by the HL tests. Furthermore, the DCA underscored the model's excellence as a predictive tool for sPTB.

Conclusions

By amalgamating patient characteristics and cervical elastography data from the second trimester, the nomogram emerged as a visually intuitive and dependable tool for predicting sPTB. Its relevance was particularly pronounced for singleton pregnancies characterized by a short CL, an absence of prior sPTB incidents, and those receiving vaginal progesterone therapy.

Vaginal progesterone for the prevention of recurrent spontaneous preterm birth

After the United States Food and Drug Administration pulled 17-alpha hydroxyprogesterone caproate from the market for its use in prevention of recurrent spontaneous preterm birth, national societies have had mixed recommendations regarding the management of patients with a singleton pregnancy and previous spontaneous preterm birth. Herein we highlight the randomized trial data and translational evidence supporting the use of vaginal progesterone for prevention of recurrent spontaneous preterm birth in singleton pregnancies. Prophylactic vaginal progesterone starting at 16 weeks and 0 days every night should be offered to patients with singletons and previous singleton spontaneous preterm birth regardless of cervical length, and continued along with placement of cerclage if a transvaginal ultrasound cervical length ≤25 mm is detected at <24 weeks.

Reassessing Preterm Birth Prevention After the Withdrawal of 17-α Hydroxyprogesterone Caproate

The U.S. Food and Drug Administration has recently withdrawn approval for 17-α hydroxyprogesterone caproate for prevention of recurrent preterm birth, and recent studies have called into question benefits of the pessary in the setting of a short cervix. Obstetric health care professionals are once again left with limited remaining options for preterm birth prevention. This narrative review summarizes the best current evidence on the use of vaginal progesterone, low-dose aspirin, and cerclage for the prevention of preterm birth; attempts to distill possible lessons learned from studies of progesterone and pessary, as well as their implementation into practice; and highlights areas where inroads into preterm birth prevention may be possible outside of the progesterone-aspirin-cerclage paradigm.

Addition of cervical elastosonography to cervical length to predict preterm birth in pregnancy women with prior preterm birth: A preliminary prospective study

OBJECTIVES

To investigate the characteristics of cervical elastosonography in pregnancies and establish an ultrasound-based combing predictor for improving the prediction in pregnant women with prior-preterm birth who might ultimately undergo preterm birth (PTB).

MATERIALS AND METHODS

169 singleton pregnancies with prior-preterm birth were examined by cervical elastography from January to November of 2021. According to the ultrasound image and result of the following-up, the patients were separated into preterm groups and full-term groups with or without cerclage. There were five elastographic parameters: Elasticity Contrast Index (ECI), Cervical hard tissue Elasticity Ratio (CHR), External Cervical os Strain rate (ES), Closed Internal Cervical os Strain rate (CIS), CIS/ES ratio and CLmin. Multivariable logistic regression was used to screen out the most significant predictors. The area under the receiver operating characteristic curve (AUC) was calculated to evaluate the ability of prediction.

RESULTS

The PTB group without cerclage showed significantly softer cervix stiffness, while those with cerclage showed significantly harder. CHRmin with P < 0.05 in the univariate logistic regression analysis was screened as a more valuable cervical elastosonography parameter than other ones. The combination of CLmin and CHRmin in un-cerclage and integrating CHRmin, maternal age and pre-pregnancy BMI in cerclage presented good predictive value. The results of AUC were higher than CLmin, respectively (0.775 vs 0.734, 0.729 vs 0.548).

CONCLUSIONS

The addition of cervical elastography parameters (such as CHRmin) might improve the ability to predict preterm birth in pregnant women with previous preterm delivery, which was better than using CL alone.

Cervical Cerclage: A Comprehensive Review of Major Guidelines

Importance

Cervical cerclage (CC) represents one of the few effective measures currently available for the prevention of preterm delivery caused by cervical insufficiency, thus contributing in the reduction of neonatal morbidity and mortality rates.

Objective

The aim of this study was to review and compare the most recently published major guidelines on the indications, contraindications, techniques, and timing of placing and removal of CC.

Evidence Acquisition

A descriptive review of guidelines from the American College of Obstetricians and Gynecologists (ACOG), the Royal College of Obstetricians and Gynaecologists (RCOG), the Society of Obstetricians and Gynaecologists of Canada (SOGC), and the International Federation of Gynecology and Obstetrics (FIGO) on CC was carried out.

Results

There is a consensus among the reviewed guidelines regarding the recommended techniques, the indications for rescue CC, the contraindications, as well as the optimal timing of CC placement and removal. All medical societies also agree that ultrasound-indicated CC is justified in women with history of prior spontaneous PTD or mid-trimester miscarriage and a short cervical length detected on ultrasound. In addition, after CC, serial sonographic measurement of the cervical length, bed rest, and routine use of antibiotics, tocolysis, and progesterone are unanimously discouraged. In case of established preterm labor, CC should be removed, according to ACOG, RCOG, and SOGC. Furthermore, RCOG and SOGC agree on the prerequisites that should be met before attempting CC. These 2 guidelines along with FIGO recommend history-indicated CC for women with 3 or more previous preterm deliveries and/or second trimester pregnancy miscarriages, whereas the ACOG suggests the use of CC in singleton pregnancies with 1 or more previous second trimester miscarriages related to painless cervical dilation or prior CC due to painless cervical dilation in the second trimester. The role of amniocentesis in ruling out intra-amniotic infection before rescue CC remains a matter of debate.

Conclusions

Cervical cerclage is an obstetric intervention used to prevent miscarriage and preterm delivery in women considered as high-risk for these common pregnancy complications. The development of universal international practice protocols for the placement of CC seems of paramount importance and will hopefully improve the outcomes of such pregnancies.

Combined vaginal progesterone and cervical cerclage in the prevention of preterm birth: a systematic review and meta-analysis

OBJECTIVE

Vaginal progesterone and cervical cerclage are both effective interventions for reducing preterm birth. It is currently unclear whether combined therapy offers superior effectiveness than single therapy. This study aimed to determine the efficacy of combining cervical cerclage and vaginal progesterone in the prevention of preterm birth.

DATA SOURCES

We searched Medline (Ovid), EMBASE (Ovid), PsycINFO (Ovid), CINAHL (EBSCOhost), Cochrane Library (Wiley), and Scopus (from their inception to 2020).

STUDY ELIGIBILITY CRITERIA

The review accepted randomized and pseudorandomized control trials, nonrandomized experimental control trials, and cohort studies. High risk patients (shortened cervical length <25mm or previous preterm birth) who were assigned cervical cerclage, vaginal progesterone, or both for the prevention of preterm birth were included. Only singleton pregnancies were assessed.

METHODS

The primary outcome was birth <37 weeks. Secondary outcomes included birth <28 weeks, <32 weeks and <34 weeks, gestational age at delivery, days between intervention and delivery, preterm premature rupture of membranes, cesarean delivery, neonatal mortality, neonatal intensive care unit admission, intubation, and birthweight. Following title and full-text screening, 11 studies were included in the final analysis. Risk of bias was assessed using the Cochrane Collaboration tool for assessing the risk of bias (ROBINS-I and RoB-2). Quality of evidence was assessed using the GRADE (Grading of Recommendations, Assessment, Development, and Evaluations) tool.

RESULTS

Combined therapy was associated with lower risk of preterm birth at <37 weeks than cerclage alone (risk ratio, 0.51; 95% confidence interval, 0.37-0.79) or progesterone alone (risk ratio, 0.75; 95% confidence interval, 0.58-0.96). Compared with cerclage only, combined therapy was associated with preterm birth at <34 weeks, <32 weeks, or <28 weeks, decreased neonatal mortality, increased birthweight, increased gestational age, and a longer interval between intervention and delivery. Compared with progesterone alone, combined therapy was associated with preterm birth at <32 weeks, <28 weeks, decreased neonatal mortality, increased birthweight, and increased gestational age. There were no differences in any other secondary outcomes.

CONCLUSION

Combined treatment of cervical cerclage and vaginal progesterone could potentially result in a greater reduction in preterm birth than in single therapy. Further, well-conducted and adequately powered randomized controlled trials are needed to assess these promising findings.

Cervical Pessary for Prevention of Preterm Birth in Individuals With a Short Cervix: The TOPS Randomized Clinical Trial

Importance

A short cervix as assessed by transvaginal ultrasound is an established risk factor for preterm birth. Study findings for a cervical pessary to prevent preterm delivery in singleton pregnancies with transvaginal ultrasound evidence of a short cervix have been conflicting.

Objective

To determine if cervical pessary placement decreases the risk of preterm birth or fetal death prior to 37 weeks among individuals with a short cervix.

Design, Setting, and Participants

We performed a multicenter, randomized, unmasked trial comparing a cervical pessary vs usual care from February 2017 through November 5, 2021, at 12 centers in the US. Study participants were nonlaboring individuals with a singleton pregnancy and a transvaginal ultrasound cervical length of 20 mm or less at gestations of 16 weeks 0 days through 23 weeks 6 days. Individuals with a prior spontaneous preterm birth were excluded.

Interventions

Participants were randomized 1:1 to receive either a cervical pessary placed by a trained clinician (n = 280) or usual care (n = 264). Use of vaginal progesterone was at the discretion of treating clinicians.

Main Outcome and Measures

The primary outcome was delivery or fetal death prior to 37 weeks.

Results

A total of 544 participants (64%) of a planned sample size of 850 were enrolled in the study (mean age, 29.5 years [SD, 6 years]). Following the third interim analysis, study recruitment was stopped due to concern for fetal or neonatal/infant death as well as for futility. Baseline characteristics were balanced between participants randomized to pessary and those randomized to usual care; 98.9% received vaginal progesterone. In an as-randomized analysis, the primary outcome occurred in 127 participants (45.5%) randomized to pessary and 127 (45.6%) randomized to usual care (relative risk, 1.00; 95% CI, 0.83-1.20). Fetal or neonatal/infant death occurred in 13.3% of those randomized to receive a pessary and in 6.8% of those randomized to receive usual care (relative risk, 1.94; 95% CI, 1.13-3.32).

Conclusions and Relevance

Cervical pessary in nonlaboring individuals with a singleton gestation and with a cervical length of 20 mm or less did not decrease the risk of preterm birth and was associated with a higher rate of fetal or neonatal/infant mortality.

Trial Registration

ClinicalTrials.gov Identifier: NCT02901626.

Society for Maternal-Fetal Medicine Statement: Response to the Food and Drug Administration's withdrawal of 17-alpha hydroxyprogesterone caproate

On April 5, 2023, the US Food and Drug Administration withdrew the approval of 17-alpha hydroxyprogesterone caproate, effective immediately, because of the lack of evidence that it reduces the risk of recurrent spontaneous preterm birth. This decision withdraws approval for all formulations of 17-alpha hydroxyprogesterone caproate (both intramuscular and subcutaneous) and applies to both brand name (Makena) and generic versions of the medication. We agree with the Food and Drug Administration determination and discourage continued prescribing of 17-alpha hydroxyprogesterone caproate, including through compounding pharmacies. We do not recommend changing indications for cerclage, indications for vaginal progesterone in patients with a short cervix, or recommendations against activity restriction based on the Food and Drug Administration withdrawal of 17-alpha hydroxyprogesterone caproate from the market. We recommend that discussion of the use of vaginal progesterone for primary prevention of recurrent preterm birth without input of cervical length or in those with a cervical length of ≥25 mm includes a shared decision-making process, especially if a progesterone formulation for preterm birth prevention was received in a previous pregnancy. The Food and Drug Administration determined that it would be inappropriate to delay the effective date of the withdrawal to allow patients currently receiving 17-alpha hydroxyprogesterone caproate to finish treatment. We agree with the Food and Drug Administration that there is no evidence of benefit with continued treatment. Patients currently receiving 17-alpha hydroxyprogesterone caproate can be counseled that the Food and Drug Administration's Center for Drug Evaluation and Research has not identified evidence of harm from discontinuation before 37 weeks of gestation.

Longitudinal change in cervical length following vaginal or abdominal cervical cerclage: a randomized comparison

BACKGROUND

Cervical cerclage has been shown to reduce the risk of recurrent spontaneous preterm birth in a high-risk patient population; however, the mechanism is not well understood. Transabdominal cerclage is superior to low and high vaginal cerclage in reducing early spontaneous preterm birth and fetal loss in women with previous failed vaginal cerclage. Cervical length measurements are commonly used to monitor high-risk women and may explain the mechanism of success.

OBJECTIVE

This study aimed to evaluate the rate of change in longitudinal cervical length after randomized placement of low transvaginal, high transvaginal, or transabdominal cerclage in women with a previous failed vaginal cerclage.

STUDY DESIGN

This was a planned analysis of longitudinal transvaginal ultrasound cervical length measurements from patients enrolled in the Vaginal Randomised Intervention of Cerclage trial, a randomized controlled trial comparing transabdominal cerclage or high transvaginal cerclage with low transvaginal cerclage. Cervical length measurements at specific gestational ages were compared over time and between groups, using generalized estimating equations fitted using the maximum-likelihood random-effects estimator. In addition, cervical length measurements were compared in women with transabdominal cerclage placed before and during pregnancy. The diagnostic accuracy of cervical length as a predictor of spontaneous preterm birth at <32 weeks of gestation was explored.

RESULTS

This study included 78 women who underwent longitudinal cervical length assessment (70% of the analyzed cohort) with a history of failed cerclage, of whom 25 (32%) were randomized to low transvaginal cerclage, 26 (33%) to high transvaginal cerclage, and 27 (35%) to transabdominal cerclage. Abdominal cerclage was superior to low (P=.008) and high (P=.001) vaginal cerclage at maintaining cervical length over the surveillance period (14 to 26 weeks of gestation) (+0.08 mm/week, 95% confidence interval, -0.40 to 0.22; P=.580). On average, the cervical length was 1.8 mm longer by the end of the 12-week surveillance period in women with transabdominal cerclage (+1.8 mm; 95% confidence interval, -7.89 to 4.30; P=.564). High vaginal cerclage was no better than low cervical cerclage in the prevention of cervical shortening; the cervix shortened by 13.2 mm over 12 weeks in those with low vaginal cerclage (95% confidence interval, -21.7 to -4.7; P=.002) and by 20 mm over 12 weeks in those with high vaginal cerclage (95% confidence interval, -33.1 to -7.4; P=.002). Preconception transabdominal cerclage resulted in a longer cervix than those performed during pregnancy; this difference was significant after 22 weeks of gestation (48.5 mm vs 39.6 mm; P=.039). Overall, cervical length was an excellent predictor of spontaneous preterm birth at <32 weeks of gestation (receiver operating characteristic curve, 0.92; 95% confidence interval, 0.82-1.00).

CONCLUSION

In women with a previous failed cervical cerclage, in the next pregnancy, the cervical length in women treated with vaginal cerclage funneled and shortened over time, whereas there was preservation of cervical length in women who receive transabdominal cerclage. Cervical length remained longer in transabdominal procedures performed before pregnancy than in transabdominal procedures performed during pregnancy. Overall, cervical length was an excellent predictor of spontaneous preterm birth in our cohort. Our findings may explain the mechanism of benefit for transabdominal cerclage, with its high placement better maintaining the structural integrity of the cervix at the level of the internal os.

What I want fellows to do: change the world!

Maternal-fetal medicine fellows and trainees in general should be inspired by their mentors to help improve clinical practice, so that pregnant individuals and their babies have better outcomes, by contributing research data in peer-reviewed manuscripts that get incorporated in national and international guidelines, and so 'change the world.'

Comparison of pregnancy outcomes of triangular 3-bites and mcdonald techniques of cervical cerclage in women with cervical insufficiency: A pilot study

Background

Cervical cerclage is the procedure of choice for preventing preterm birth due to cervical insufficiency. Despite the simplicity of the McDonald's method of cerclage application, it is still technically difficult to take four bites around the cervix before knotting. There is a need to develop a simpler method of cervical cerclage application with similar or improved pregnancy outcomes.

Aim

This is to compare the ease/duration of application and pregnancy outcomes of the new triangular three-bite cervical cerclage technique and McDonald's technique in women with cervical insufficiency.

Patients and Methods

This is a pilot study with 20 participants that met the inclusion criteria. They were randomly grouped into triangular three-bite method (n = 10) and McDonald's method (n = 10). The pregnancy outcomes were compared between the groups with the Chi-square test and student's t-test. A P value of <.05 was set as level of significance.

Results

The sociodemographic characteristics of the two groups were similar. There was no statistically significant difference between the two groups regarding the pregnancy outcome (spontaneous miscarriage P = 1.00, preterm delivery P = 0.61, and neonatal birthweight P = 0.96). However, the duration of cerclage application (5.98 ± 1.79 minutes vs. 14.25 ± 7.5 minutes; P <.002) and estimated blood loss (29 ± 9.94 mls vs. 48.5 ± 25.82 mls; P = .04) were significantly lower in the triangular three-bite arm than in the McDonald's arm.

Conclusion

The new triangular three-bite technique has similar pregnancy outcomes with the conventional McDonald's technique and has shown a lower duration of procedure and blood loss. Since this is a pilot study, a well-structured randomized control trial to compare the two methods is recommended.

Growing threat of extended-spectrum β-lactamase-producing Enterobacteriaceae colonisation in high-risk pregnancies: A cross-sectional study

OBJECTIVE

To investigate the epidemiological changes in extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBL-E) vaginal colonisation in pregnant women deemed at high risk, and to identify independent risk factors. Further, the differences in perinatal outcomes according to maternal ESBL-E vaginal colonisation were analysed.

DESIGN

Cross-sectional study.

SETTING

Republic of Korea.

POPULATION

A cohort of 1460 women admitted to our high-risk pregnancy unit between 14⁺⁰ and 36⁺⁶  weeks of gestation.

METHODS

The trend of changes in the association of ESBL-E vaginal colonisation from January 2010 to December 2020 was analysed. The main outcomes were analysed over the study period and ESBL-E vaginal colonisation.

MAIN OUTCOME MEASURES

Rate of ESBL-E vaginal colonisation, risk factors for ESBL-E vaginal colonisation and perinatal outcomes.

RESULTS

The ESBL-E vaginal colonisation rate has tended to increase over the past 11 years, which was attributed to a significantly higher proportion of ESBL-producing Escherichia coli. Cerclage (RR 3.7, 95% CI 2.19-6.40) and prior antibiotic treatment (RR 4.0, 95% CI 2.44-6.54) were found as independent risk factors for ESBL-E vaginal colonisation. Earlier gestational age at delivery and higher proven early-onset neonatal sepsis (EONS) rate were observed in the ESBL-E-positive group.

CONCLUSIONS

The ESBL-E vaginal colonisation rate in pregnant patients at high risk has increased over the past decade, and the independent risk factors for colonisation are cerclage and prior antibiotic treatment. Additionally, maternal ESBL-E vaginal colonisation is associated with higher rates of proven EONS.

McDonald versus Shirodkar cerclage technique in the prevention of preterm birth: A systematic review and meta-analysis

BACKGROUND

Cervical cerclage has been used for decades to reduce preterm birth. The Shirodkar and McDonald cerclage are the most commonly used techniques with no current consensus on the preferred technique.

OBJECTIVE

To compare the efficacy of the Shirodkar and McDonald cerclage techniques in preventing preterm birth.

SEARCH STRATEGY

Studies were sourced from six electronic databases and reference lists.

SELECTION CRITERIA

Studies including women with a singleton pregnancy, requiring a cervical cerclage, using either the Shirodkar or McDonald technique that ran comparative analyses between the two techniques.

DATA COLLECTION AND ANALYSIS

The primary outcome was preterm birth before 37 weeks, with analyses at 28, 32, 34 and 35 weeks. Secondary data were also collected on neonatal, maternal and obstetric outcomes.

MAIN RESULTS

Seventeen papers were included: 16 were retrospective cohort studies and one was a randomised controlled trial. The Shirodkar technique was significantly less likely to result in preterm birth before 37 weeks than the McDonald technique (relative risk [RR] 0.91, 95% CI 0.85-0.98). This finding was supported by a statistically significant reduction in rates of preterm birth before 35, 34 and 32 weeks, PPROM, difference in cervical length, cerclage to delivery interval, and an increase in birthweight in the Shirodkar group. No difference was seen in preterm birth rates <28 weeks, neonatal mortality, chorioamnionitis, cervical laceration or caesarean section rates. The RR for preterm birth prior to 37 weeks was no longer significant when sensitivity analyses were performed removing studies with a serious risk of bias. However, similar analyses removing studies that utilised adjunctive progesterone strengthened the primary outcome (RR 0.83, 95% CI 0.74-0.93).

CONCLUSION

Shirodkar cerclage reduces the rate of preterm birth prior to 35, 34 and 32 weeks' gestation when compared with McDonald cerclage; however, the overall quality of the studies in this review is low. Further, large, well-designed randomised controlled trials are required to address this important question to optimise care for women who may benefit from cervical cerclage.

Vaginal progesterone for the prevention of preterm birth: who can benefit and who cannot? Evidence-based recommendations for clinical use

Vaginal progesterone (VP) has been recommended to prevent preterm birth (PTB) in women at high-risk. However, there is controversy as to whether VP is efficacious in some subsets of high-risk women. In this review, we examined the current best evidence on the efficacy of VP to prevent PTB in several subsets of high-risk women and provided recommendations for its clinical use. Compelling evidence indicates that VP reduces the risk of PTB and improves perinatal outcomes in singleton gestations with a short cervix (≤25 mm), both with and without a history of spontaneous PTB. VP appears promising to reduce the risk of PTB in twin gestations with a short cervix (≤25 mm) and in singleton gestations conceived by assisted reproductive technologies, but further research is needed. There is no convincing evidence that supports prescribing VP to prevent PTB in singleton gestations based solely on the history of spontaneous preterm birth. Persuasive evidence shows that VP does not prevent PTB nor does it improve perinatal outcomes in unselected twin gestations and in singleton gestations with a history of spontaneous PTB and a cervical length >25 mm. There is no evidence supporting the use of VP to prevent PTB in triplet or higher-order multifetal gestations, singleton gestations with a positive fetal fibronectin test and clinical risk factors for PTB, and gestations with congenital uterine anomalies or uterine leiomyoma. In conclusion, current evidence indicates that VP should only be recommended in singleton gestations with a short cervix, regardless of the history of spontaneous PTB.

The Association of Inflammatory Markers with Maternal-Neonatal Outcome After Cervical Cerclage

Objective

Cervical cerclage is effective in prolonging the number of weeks gestation in patients with cervical insufficiency(CI). However, valuable predictors with successful cervical cerclage remain limited. It aimed to evaluate the value of the systemic immune-inflammation index (SII), and systemic inflammation response index (SIRI) to predict the outcomes of cervical cerclage.

Methods

This study analyzed 374 participants. Inflammatory markers were calculated using maternal peripheral blood. The association of inflammatory markers and the outcome of cervical cerclage were analyzed. And the optimal cut-off values of inflammatory markers were calculated. Also, the Chi-square test and logistic and linear regression analyses were performed to evaluate inflammatory markers with the maternal outcome and neonatal outcomes.

Results

374 pregnancies were included in this study. Finally, 268 (71.7%) participants suffered successful cervical cerclage. This study demonstrated that the baseline BMI (cm²/kg), the bulging membrane, cervical dilation (≥2cm), the amniotic sac herniation, the neutrophils counts, the systemic immune-inflammation index (SII), and systemic inflammation response index (SIRI) were significant difference between the successful and unsuccessful groups (all P<0.05). Additionally, maternal blood inflammatory markers, such as WBC, lymphocyte, neutrophils, monocyte, platelet counts, SII, and SIRI, were significantly associated with maternal-neonatal outcomes. Furthermore, the results demonstrated that the SII level had the highest OR (OR=4.626; 95% CI (2.500-8.560)), as well as the following: SIRI level (OR = 3.795; 95% CI (1.989-7.242)), cervical dilation (≥2cm) (OR =3.477; 95% CI (1.458-10.844)), and amniotic sac herniation (OR = 1.796; 95% (0.473-4.975)).

Conclusion

This study demonstrated that the baseline SII level and SIRI level are important biochemical markers for predicting the outcome of cervical cerclage and maternal-neonatal outcomes with non-invasive procedures. They can help to provide personalized treatment before surgery and enhance postoperative surveillance.

Comparison of two stitches versus one stitch for emergency cervical cerclage to prevent preterm birth in singleton pregnancies

OBJECTIVE

To compare the efficacy of two stitches versus one stitch in women with emergency cervical cerclage.

METHODS

A retrospective case-control study of 26 women with singleton pregnancies who underwent emergency cervical cerclage before 26 weeks. A comparison was made between patients with two stitches versus one stitch at the time of cervical cerclage placement. The primary outcome was gestational age (GA) at delivery and preterm birth (PTB) before 37, 34, 32, 28, and 24 weeks.

RESULTS

Average GA at delivery in the two-stitches group was significantly greater than in the one-stitch group (32.71 ± 5.54 weeks vs 27.99 ± 4.70 weeks, P = 0.028). There were significant decreases in the incidence of spontaneous PTB at <34 weeks and less than 32 weeks in the two-stitches group (P = 0.034; P = 0.013, respectively). The neonatal intensive care unit (NICU) admissions rate and length of stay in the NICU in the two-stitches group were significantly reduced (P = 0.035 and P = 0.018, respectively). However, there was no significant difference in neonatal mortality between the two groups.

CONCLUSION

Compared with emergency cervical cerclage placement with one stitch, the procedure with two stitches can prolong the pregnancy and improve the neonatal prognosis more effectively.

Proposed staging criteria for sonographic and physical exam for cervical changes at <24 weeks gestation to predict preterm birth

Asymptomatic cervical changes, such as cervical length shortening and dilation, which often occur before spontaneous preterm birth, have been described well in singleton pregnancies with or without history of preterm birth. The current screening strategies available to identify patients at increased risk of spontaneous preterm birth include use of transvaginal ultrasound for cervical length assessment and for detection of a short cervical length (≤25 mm) before 24 weeks of gestation. Whether an additional evaluation of the cervix (ie, via speculum or manual exam) is indicated is often pondered by clinicians and may depend on how short the cervical length is and if there is a history of preterm birth. Based on expert opinion, we developed a novel staging system of asymptomatic cervical changes including the following: cervical length measurement, cervical and membrane appearance on speculum exam, and cervical dilation by manual exam. This staging system, if proven accurate, may aid in standardizing definitions for purposes of patient prognosis, evaluation of intervention efficacy, and clinical management.

IMPaCT: A Pilot Randomized Trial of an Intervention to Reduce Preterm Birth Among Non-Hispanic Black Patients at High Risk

Introduction

Preterm birth is a major cause of neonatal morbidity and mortality rate. Non-Hispanic black patients disproportionately experience preterm birth and nonadherence to evidence-based preventive measures. Interventions tailored to non-Hispanic black birthing individuals (NHBBIs) that address barriers to preterm birth preventions are urgently needed.

Methods

Together with a community-engaged multidisciplinary stakeholder group, we developed an intervention to improve adherence to preterm birth preventions among black pregnant patients with prior preterm birth. The intervention included the following: (1) preterm birth prevention education, (2) an employment navigation toolkit, and (3) encouragement text messages. We piloted the intervention by recruiting self-identified non-Hispanic black patients at or before 20 weeks of gestation with a prior preterm birth and randomizing them to the intervention or an active control. The primary outcomes were feasibility and acceptability. Our secondary outcomes were preliminary efficacy based on birth outcomes, patient experience, and pregnancy-specific anxiety (PSA). Descriptive statistics, analysis of verbatim survey responses, Wilcoxon signed rank, and Fisher's exact were used to describe and compare quantitative and qualitative data.

Results

We identified 53 individuals who met the inclusion criteria, 35 were reachable remotely and 30 were enrolled and randomized. More than 80% (n=26) were retained throughout the study, and 100% of participants identified at least one intervention component as helpful. In this small pilot, there were no detectable differences in adherence to preterm birth preventive recommendations. No difference in preterm births, other pregnancy, or patient experience outcomes was detected between the intervention and active control participants.

Discussion

The intervention is feasible and acceptable. Larger, appropriately powered studies are needed to assess whether the intervention will decrease PSA and reduce preterm birth. This trial was registered with ClinicalTrials.gov (NCT04933812).

Which part of cervical length is predictive of preterm birth in women with cerclage?

OBJECTIVE

To evaluate the predictive value of transvaginal ultrasonography measures: total cervical length (TCL), length to internal OS (LIO) and external OS (LEO) from the cerclage following cerclage placement, for spontaneous preterm birth (PTB).

METHODS

A retrospective cohort at a single tertiary care center (2010-2020). Women with McDonald cerclage were evaluated during the 2nd and 3rd trimesters for cervical measurements: TCL, LIO, LEO. The primary outcome was PTB < 37 weeks. Demographic data, obstetric history, delivery information and serial cervical length measurements were collected. Subgroup analyses were performed to evaluate cervical length parameters (as described) and PTB rates prior to 34, 32 and 28 weeks of gestation.

RESULTS

Of 66 women enrolled, 36.4% (n = 24) had PTB. There were no differences in the obstetrical history and demographic information (p > .05) nor indication for cerclage (p = .369). Cervical length measurements at 20-24 weeks demonstrated a shorter TCL & LIO (22.69 vs. 33.86 mm, p = .001; 9.25 vs. 15.9 mm, p = .0042; respectively) in the preterm group. The LEO was similar in both groups. This pattern was also shown in a subgroup analysis (PTB < 34, 32 and 28 weeks).

CONCLUSION

Cervical length from internal OS to cerclage and total cervical length have a predictive value for PTB in women with a cervical cerclage, regardless of the indication for cerclage/previous pregnancy outcomes. Our data emphasize the importance of follow-up cervical length measurements of women with a cervical cerclage, and especially cervical length from internal OS to cerclage as those women may need additional care.

Comparison of transvaginal cervical cerclage versus laparoscopic abdominal cervical cerclage in cervical insufficiency: a retrospective study from a single centre

Background

Cervical cerclage has been proposed as an effective treatment for cervical insufficiency, but there has been controversy regarding the surgical options of cervical cerclage in singleton and twin pregnancies. This study aimed to compare the pregnancy outcomes between transvaginal cervical cerclage (TVC) and laparoscopic abdominal cervical cerclage (LAC) in patients with cervical insufficiency. We also aimed to evaluate the efficacy and safety, and provide more evidence to support the application of cervical cerclage in twin pregnancies.

Methods

A retrospective study was carried out from January 2015 to December 2021. The primary outcomes were the incidence of spontaneous preterm birth (sPTB) < 24 weeks, < 28, < 32, < 34 weeks, and < 37weeks, gestational age at delivery, and the incidence of admission for threatened abortion or preterm birth after cervical cerclage. The secondary outcomes included admission to the Neonatal Intensive Care Unit, adverse neonatal outcomes and neonatal death. We also analysed the pregnancy outcomes of twin pregnancies after cervical cerclage.

Results

A total of 289 patients were identified as eligible for inclusion. The LAC group (n = 56) had a very low incidence of sPTB ˂ 34 weeks, and it was associated with a significant decrease in sPTB < 28 weeks, ˂32 weeks, ˂34 and < 37 weeks, and admission to the hospital during pregnancy for threatened abortion or preterm birth after cervical cerclage (0 vs.27%; 1.8% vs. 40.3%; 7.1% vs. 46.8%; 14% vs. 63.5%, 8.9% vs. 62.2%, respectively; P < 0.001), and high in gestational age at delivery compared with the TVC group (n = 233) (38.3 weeks vs.34.4 weeks,P < 0.001). Neonatal outcomes in the LAC group were significantly better than those in the TVC group. The mean gestational age at delivery was 34.3 ± 1.8 weeks, with a total foetal survival rate of 100% without serious neonatal complications in twin pregnancies with LAC.

Conclusion

In patients with cervical insufficiency, LAC appears to have better pregnancy outcomes than TVC. For some patients, LAC is a recommended option and may be selected as the first choice. Even in twin pregnancies, cervical cerclage can improve pregnancy outcomes with a longer latency period, especially in the LAC group.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-022-05108-w.

Cervical length distribution among Brazilian pregnant population and risk factors for short cervix: A multicenter cross-sectional study

Objective

Since there are populational differences and risk factors that influence the cervical length, the aim of the study was to construct a populational curve with measurements of the uterine cervix of pregnant women in the second trimester of pregnancy and to evaluate which variables were related to cervical length (CL) ≤25 mm.

Materials and methods

This was a multicenter cross-sectional study performed at 17 hospitals in several regions of Brazil. From 2015 to 2019, transvaginal ultrasound scan was performed in women with singleton pregnancies at 18 0/7 to 22 6/7 weeks of gestation to measure the CL. We analyzed CL regarding its distribution and the risk factors for CL ≤25 mm using logistic regression.

Results

The percentage of CL ≤ 25mm was 6.67%. Shorter cervices, when measured using both straight and curve techniques, showed similar results: range 21.0–25.0 mm in straight versus 22.6–26.0 mm in curve measurement for the 5^th percentile. However, the difference between the two techniques became more pronounced after the 75^th percentile (range 41.0–42.0 mm straight x 43.6–45.0 mm in curve measurement). The risk factors identified for short cervix were low body mass index (BMI) (OR: 1.81 CI: 1.16–2.82), higher education (OR: 1.39 CI: 1.10–1.75) and personal history ([one prior miscarriage OR: 1.41 CI: 1.11–1.78 and ≥2 prior miscarriages OR: 1.67 CI: 1.24–2.25], preterm birth [OR: 1.70 CI: 1.12–2.59], previous low birth weight <2500 g [OR: 1.70 CI: 1.15–2.50], cervical surgery [OR: 4.33 CI: 2.58–7.27]). By contrast, obesity (OR: 0.64 CI: 0.51–0.82), living with a partner (OR: 0.76 CI: 0.61–0.95) and previous pregnancy (OR: 0.46 CI: 0.37–0.57) decreased the risk of short cervix.

Conclusions

The CL distribution showed a relatively low percentage of cervix ≤25 mm. There may be populational differences in the CL distribution and this as well as the risk factors for short CL need to be considered when adopting a screening strategy for short cervix.

Pre-Cerclage cervical length predicts long-term pregnancy sustenance: A case-control study

Background

This study aimed to assess a predictor of long-term pregnancy sustenance post cervical cerclage in women with or without a medical history of cervical insufficiency.

Materials and methods

We included pregnant women who underwent cerclage at 12–25 weeks gestation in four perinatal medical centers between January 2009 and December 2010. We classified the cerclage modality as ultrasound-indicated cervical cerclage if the pre-cerclage CL was <25 mm because the prophylactic and therapeutic cerclage definitions varied among institutions. The procedure was deemed successful if the pregnancy continued for more than 13 weeks post cerclage. We compared the outcomes of women who underwent successful and unsuccessful cerclage and investigated whether the pre-cerclage CL could predict pregnancy outcomes in women who underwent successful cerclage using receiver-operating characteristic curves.

Results

We screened 114 pregnant women; 91 met the inclusion criteria. Pre-cerclage CL was a moderately accurate predictor of long-term pregnancy sustenance in the successful group (optimal cut-off value: 17 mm; area under the curve: 0.76; P = 0.0016). Approximately 87% of patients with a pre-cerclage CL ≥ 17 mm sustained their pregnancies for more than 13 weeks post cerclage; however, 64% of patients with a pre-cerclage CL < 17 mm did not.

Conclusion

We speculate that the use of other treatment options in addition to cerclage in women with a pre-cerclage CL < 17 mm may result in a successful pregnancy.

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Cervical cerclage encompasses many indications and specific techniques.

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Pre-cerclage cervical length (CL) predicts long-term pregnancy sustenance.

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87% women (pre-cerclage, CL ≥ 17 mm) sustained their pregnancy for >13 weeks.

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64% women (pre-cerclage, CL < 17 mm) did not sustain their pregnancy for >13 weeks.

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Cerclage can be considered in women with a pre-cerclage CL < 17 mm.

New Indication for an Established Procedure: Cervical Cerclage for Prevention of Umbilical Cord Prolapse

Objective:

Funic presentation is a risk factor for umbilical cord prolapse. In the majority of cases, umbilical cord prolapse is an obstetric emergency. Currently there is no strategy to prevent umbilical cord prolapse in patients with funic presentation. Placing a third trimester cervical cerclage was proposed, as a mechanical barrier of prolapse, in women with funic presentation.

Materials and Methods:

Twelve patients with funic presentation, detected between 23 and 34 weeks of gestation, were included in the study. Patients were informed that although cervical cerclage have been widely used in obstetrics, it had not been offered in patients with funic presentation. Gestational age at delivery, mode of delivery, location of umbilical cord at birth, presence or absence of umbilical cord prolapsed, and neonatal condition at birth were recorded in all cases.

Results:

Patients’ age varied from 21 to 40 years, mean of 28 ± 6.2 years, and gestational age at the time of diagnosis of funic presentation varied from 26 to 34 weeks of pregnancy. All patients were seen weekly after the cervical cerclage placement to assess the umbilical cord location. Seven patients had vertex presentation, four had breech presentation, and one had transverse lie presentation. A follow-up sonogram of the umbilical cord revealed the following: funic presentation was persistent throughout the entire pregnancy in five patients, disappeared in four, and became intermittent in three. The delivery mode was as follows: cesarean section was performed in eight patients (five with persistent funic presentation, two with intermittent, and one with resolved funic presentation because of failure to progress in labor). There were five patients who delivered vaginally. Funic presentation was confirmed in all patients who underwent cesarean sections. None of the patients had had an umbilical cord prolapse.

Conclusion:

In view of high perinatal mortality of umbilical cord prolapses, placement of cervical cerclage could be added to obstetric armamentarium in patients with funic presentation, after proper counseling.

"Advances in Preterm Delivery"-How Can We Advance Further?

Preterm delivery (PTD: <37 gestational weeks) complicates 5−13% of deliveries worldwide [...]