"Does the use of gestation-specific centiles for cervical length change the management of pregnancies at risk of recurrent spontaneous preterm birth?"

INTRODUCTION

Preterm birth is the leading cause of neonatal morbidity and mortality. Spontaneous Preterm Birth (sPTB) has many and varied causes but is known to be strongly associated with a short or shortening cervix in the midtrimester of pregnancy. The strongest risk factor for sPTB is a previous sPTB. In women with a history of sPTB, we can offer surveillance and treatments which have been proven to reduce the risk of sPTB, such as cervical cerclage and vaginal progesterone supplementation. Alongside other indications, we currently use 25 mm or shorter as a "trigger threshold" for offering cervical cerclage treatment in the Preterm Birth Prevention Clinic at The National Maternity Hospital.

AIM

To determine if using gestation-specific centiles instead of a 25 mm cut-off for cervical length changes the antenatal management of women at high risk of sPTB.

METHOD

This was a retrospective chart review of all women attending the preterm birth clinic over the 2-year period 2018-2020 in a large tertiary referral unit in Dublin, Ireland. Demographic details, obstetric history, preterm birth risk factors and preventative treatments offered were collected and analysed. Cervical lengths were measured with ultrasound using a standardised protocol and all performed or supervised by 2 experienced sonographers.

RESULTS

A total of 200 patients with known risk factors for sPTB attended the Preterm Birth Surveillance Clinic at the National Maternity Hospital during the study period. Of these, 36/200 (18%) went on to deliver again prior to 37 weeks despite attending the clinic +/- receiving interventions & this group are the focus of this paper. The indications for surveillance in this group that had a recurrent sPTB included recurrent second-trimester pregnancy losses/preterm delivery < 34 weeks (26/36 (72%)), cervical trauma (including treatment of CIN) (12/36 (33%)), congenital abnormalities (1/36 (2.8%)), uterine anomaly (1/36 (2.8%)) and placental bleeding (1/36 (2.8%)). There was one smoker in this series. Funnelling was observed in 3/36 cases (8.3%). Of the 36 patients, an additional 15 would have received a cerclage had gestation-specific centiles, i.e., <5th centile, been used and an additional 10/36 (28%) would have been offered progesterone therapy.

CONCLUSION

In those at high risk of preterm birth, the use of gestation-specific centiles for cervical length increases the proportion of patients that would be eligible for cervical cerclage. It is unclear whether this would change clinical outcome.

Effectiveness of combined vaginal progesterone and cervical cerclage in preventing preterm birth: a systematic review and meta-analysis protocol

INTRODUCTION

Preterm birth (PTB) is the leading cause of death in children under 5 years. Preventive therapies targeted towards women with risk factors such as a prior PTB or a short cervix reduce the rate of PTB. Cervical cerclage, vaginal progesterone and a combination of the two have been used with no consensus as to whether combined treatment is more effective than any single treatment alone. The objective of this review is to determine the efficacy of combined treatment compared with cerclage alone and combined treatment compared with progesterone alone.

METHODS AND ANALYSIS

Studies will be sourced from the electronic databases Medline (Ovid), EMBASE (Ovid), PsycINFO (Ovid), Scopus, CINAHL (EBSCOhost) and Cochrane Library (Wiley) and reference lists. We will not exclude any papers due to publication date. Randomised control trials (RCTs), non-RCTs and cohort studies assessing single therapy (either progesterone or cerclage) versus combined therapy in women with a singleton pregnancy will be included. Two independent reviewers will conduct study screening (at abstract and full-text level), data extraction and risk of bias assessment with disagreements resolved by an experienced researcher. Random or fixed effects models will be used depending on data heterogeneity and data will be presented as risk ratio for dichotomous data or mean difference for continuous data with a CI of 95% used for all outcomes.

ETHICS AND DISSEMINATION

Not applicable due to nature of the study type.

PROSPERO REGISTRATION NUMBER

CRD42020195975.

A Novel Transvaginal Cervical Cerclage Model for Resident Training

INTRODUCTION

Vaginal suturing can be challenging to teach and learn due to the surgical assistant's limited operative field visualization. Data on resident training and comfort with cerclage placement using models are limited. The aim of this activity was to assess learner satisfaction with practice using a novel model allowing for full visualization during transvaginal cervical cerclage placement.

METHODS

OB/GYN residents participated in a 1-hour combined lecture and hands-on cerclage training simulation with the novel model. Pre- and postsession survey responses were assessed with descriptive statistics and paired t tests.

RESULTS

Twenty residents with a median of 2 (SD = 1.6) years of residency experience participated. Ninety-five percent reported no prior cerclage simulation training; 60% reported placing cerclages in practice. Pre- and posttest analysis indicated a significant decrease in perceived need for further training (M = 4.05, SD = 1.07, vs. M = 3.45, SD = 0.86; p = .024) and an increase in comfort performing a cerclage placement (M = 2.55, SD = 1.16, vs. M = 3.85, SD = 0.79; p < .001). After the simulation, residents reported more comfort in cerclage placement with decreasing supervision (M = 2.05, SD = 1.02, vs. M = 2.30, SD = 1.01; p = .021); 90% reported that learning to place a cerclage was easy.

DISCUSSION

Implementing a novel, low-cost model allowing full operative field visualization significantly improved reported comfort regarding cervical cerclage placement and resulted in high satisfaction amongst residents. Future research should evaluate the training's impact on clinical skills.

Optimal timing of cervical cerclage removal following preterm premature rupture of membranes; a retrospective analysis

OBJECTIVE

Preterm prelabour rupture of membranes occurs in over one third of pregnant women with a cervical cerclage in situ. In the setting of preterm prelabour rupture of membranes, clinicians are faced with the difficult decision of the optimal timing for removing the cerclage. We compared the maternal and neonatal outcomes following immediate removal or retention of the cervical cerclage.

STUDY DESIGN

Women were retrospectively identified from St Thomas's Hospital Preterm Surveillance clinic database. Asymptomatic women with preterm prelabour rupture of membranes were identified and separated into those that had the cerclage removed and those that had the cerclage retained within 24 h of presentation. Women who were symptomatic at presentation and who delivered within 24 h of presentation were excluded from the analysis. Maternal outcomes measured were latency between preterm prelabour rupture of membranes and delivery, gestation at delivery and maternal chorioamnionitis and infection markers. Neonatal outcomes including birthweight and Apgar scores were also measured.

RESULTS

43 women with cerclage retained for over 24 h following preterm prelabour rupture of membranes were compared to 25 women in whom the cerclage was removed. The latency between preterm prelabour rupture of membranes and delivery was on average 70.4 h longer in women who had their cerclage retained compared to the removed group (p = 0.009). Rates of chorioamnionitis, maternal blood results, neonatal birthweight and Apgar scores did not differ significantly between the two groups, however a trend towards higher rates of chorioamnionitis (60 % vs 45 %) were seen in the retained group.

CONCLUSION

Cervical cerclage retention in women following preterm prelabour rupture of membranes was associated with a longer latency period to delivery and was not significantly associated with any adverse obstetric, maternal or neonatal outcomes. Therefore, in women at risk of spontaneous preterm birth, cerclage retention may be beneficial, however these women and their babies should be monitored closely for any signs of infection. Further prospective randomised controlled studies assessing these outcomes as well as longer-term outcomes in these women and their children are needed.

Laparoscopic emergency cervicoisthmic cerclage in second trimester of pregnancy: A case series report

PURPOSE

The aim of this study was to evaluate the feasibility and safety of Laparoscopic emergency cervicoisthmic cerclage in second trimester of pregnancy.

METHODS

Between November 2015 and March 2019 5 patients underwent Laparoscopic emergency cervicoisthmic cerclage. All women had showed cervical insufficiency with dilation in the second trimester due to extensive conisation (3 patients) or re-conisation (2 patients) and failed transvaginal cerclage (5 patients) due to a short vaginal cervix. Patients' characteristics were obtained from hospital's medical record and we evaluated surgical data, intra, postoperative complications, and perinatal outcome. All operations were performed by the same surgeon.

RESULTS

The average operation time was 88 min (ranging from 80 to 95 minutes), the average estimated blood loss during the procedure was less than 100 mL and there were no perioperative or postoperative complications. The mean gestational age at surgery was 14.4 (ranging from 14.2 to 16) weeks. All women underwent an elective CS after 38 weeks of gestation. The overall pregnancy survival rate was 100 %, the mean gestational age at delivery was 38.1 weeks (ranging from 38.0 to 38.5 weeks) and the mean birth weight was 3190 g (g) (ranging from 2980 g to 3350 g).

CONCLUSION

Laparoscopic cervicoisthmic cerclage might be an alternative approach even in the early second trimester of pregnancy. Our study's success rates compare favourably to the laparotomy approach and the laparoscopic cervicoisthmic cerclage showed a relatively high success rate in women who are at risk of poor obstetric outcomes. Of course, the surgeon's experience and competence plays a key role and this approach should only be attempted in well-organized units.

[MAVRIC study: when abdominal cerclage is preferable to vaginal cerclage]

Vaginal cerclage can be used to treat cervical incompetence, thus reducing the risk of an unfavourable outcome. However, in some cases, it can be ineffective. One of the challenges for the gynaecologist-obstetrician is how to deal with a subsequent pregnancy after a failure of vaginal cerclage. The recently published MAVRIC study shows that performing abdominal cerclage prior or at the beginning of pregnancy reduces the rate of late miscarriage and premature delivery compared to vaginal cerclage. This implies a birth by caesarean section, and therefore a second surgery for the woman. However, it remains to determine the best surgical technique for abdominal cerclage. In the MAVIRC study, cerclage was done by laparotomy. It shall be elucidated whether this technique is superior to laparoscopy.

Effectiveness of cervical pessary compared to cervical cerclage with or without vaginal progesterone for the prevention of preterm birth in women with twin pregnancies and a short cervix: study protocol for a two-by-two factorial randomised clinical trial

INTRODUCTION

Women with twin pregnancies and a short cervix are at increased risk for preterm birth (PTB). Given the burden of prematurity and its attendant risks, the quest for effective interventions in twins has been an area of considerable research. Studies investigating the effectiveness of cervical cerclage, cervical pessary and vaginal progesterone in preventing PTB have yielded conflicting results. The aim of this study is to compare the effectiveness of cervical pessary and cervical cerclage with or without vaginal progesterone to prevent PTB in women with twin pregnancies and a cervical length (CL) ≤ 28 mm.

METHODS AND ANALYSIS

This multicentre, randomised clinical trial will be conducted at My Duc Hospital and My Duc Phu Nhuan Hospital, Vietnam. Asymptomatic women with twin pregnancies and a CL ≤28 mm, measured at 16-22 weeks' gestation, will be randomised in a 1:1:1:1 ratio to receive a cerclage, pessary, cerclage plus progesterone or pessary plus progesterone. Primary outcome will be PTB <34 weeks. Secondary outcomes will be maternal and neonatal complications. We preplanned a subgroup analysis according to CL from all women after randomisation and divided into four quartiles. Analysis will be conducted on an intention-to-treat basis. The rate of PTB <34 weeks' gestation in women with twin pregnancies and a cervix ≤28 mm and treated with pessary in our previous study at My Duc Hospital was 24.2%. A sample size of 340 women will be required to show or refute that cervical cerclage decreases the rate of PTB <34 weeks by 50% compared with pessary (from 24.2% to 12.1%, α level 0.05, power 80%, 5% lost to follow-up and protocol deviation). This study is not to be powered to assess interactions between interventions.

ETHICS AND DISSEMINATION

Ethical approval was obtained from the Institutional Ethics Committee of My Duc Hospital and informed patient consent was obtained before study enrolment. Results of the study will be submitted for publication in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

NCT03863613 (date of registration: 4 March 2019).

Effect of Cervical Cerclage on the Risk of Recurrent Preterm Birth after a Twin Spontaneous Preterm Birth

BACKGROUND

This study aimed to evaluate the effect of cervical cerclage on the recurrence risk for preterm birth in singleton pregnant women after a twin spontaneous preterm birth (sPTB).

METHODS

This multicenter retrospective cohort study included women who had a singleton pregnancy from January 2009 to December 2018 at 10 referral hospitals and a twin sPTB before the current pregnancy. We compared the cervical lengths during pregnancy and pregnancy outcomes, according to the placement of prophylactic or emergency cerclage. We evaluated the independent risk factors for sPTB (< 37 weeks of gestation) in a subsequent singleton pregnancy.

RESULTS

For the index singleton pregnancy, preterm birth occurred in seven (11.1%) of 63 women. There was no significant difference in the cervical lengths during pregnancy in women with and without cerclage. In a multivariate logistic regression analysis, the placement of emergency cerclage was an independent risk factor for subsequent singleton preterm birth (odds ratio [OR], 93.188; 95% confidence interval [CI], 1.633-5,316.628; P = 0.027); however, the placement of prophylactic cerclage (OR, 19.264; 95% CI, 0.915-405.786; P = 0.057) was not a factor. None of the women who received prophylactic cerclage delivered before 35 weeks' gestation in the index singleton pregnancy.

CONCLUSION

Cerclage did not lower the risk of preterm birth in a subsequent singleton pregnancy after a twin sPTB. However, emergency cerclage was an independent risk factor for preterm birth and there was no preterm birth before 35 weeks' gestation in the prophylactic cerclage group. Therefore, close monitoring of the cervical length and prophylactic cerclage might be considered in women who have experienced a twin sPTB at extreme gestation.

[Preterm delivery: an overview on prediction, prevention and treatment]

Due to a low level of understanding of mechanisms involved in spontaneous preterm delivery there is a lack of reliable biomarkers. Existing biomarkers have a low positive predictive value but a high negative predictive value. Use of tests with high negative predictive value will reduce unnecessary interventions and hospitalization of women with threatening preterm delivery. When given to the right pregnant women, antenatal corticosteroid treatment are still the most important obstetrical intervention and reduces both neonatal mortality and short- and long-term morbidity.Several ongoing national Swedish multicenter studies may increase the understanding of the roles of cervical length, preeclampsia screening and magnesium sulfate dosage in the context of preterm delivery in a Nordic setting. Major development has been achieved in prediction and prevention of preterm preeclampsia at the cost of a 10% screen positive rate.

Evidence that antibiotic administration is effective in the treatment of a subset of patients with intra-amniotic infection/inflammation presenting with cervical insufficiency

BACKGROUND

Cervical insufficiency is a risk factor for spontaneous midtrimester abortion or early preterm birth. Intra-amniotic infection has been reported in 8-52% of such patients and intra-amniotic inflammation in 81%. Some professional organizations have recommended perioperative antibiotic treatment when emergency cervical cerclage is performed. The use of prophylactic antibiotics is predicated largely on the basis that they reduce the rate of complications during the course of vaginal surgery. However, it is possible that antibiotic administration can also eradicate intra-amniotic infection/inflammation and improve pregnancy outcome.

OBJECTIVE

To describe the outcome of antibiotic treatment in patients with cervical insufficiency and intra-amniotic infection/inflammation.

STUDY DESIGN

The study population consisted of 22 women who met the following criteria: (1) singleton pregnancy; (2) painless cervical dilatation of >1 cm between 16.0 and 27.9 weeks of gestation; (3) intact membranes and absence of uterine contractions; (4) transabdominal amniocentesis performed for the evaluation of the microbiologic and inflammatory status of the amniotic cavity; (5) presence of intra-amniotic infection/inflammation; and (6) antibiotic treatment (regimen consisted of ceftriaxone, clarithromycin, and metronidazole). Amniotic fluid was cultured for aerobic and anaerobic bacteria and genital mycoplasmas, and polymerase chain reaction for Ureaplasma spp. was performed. Intra-amniotic infection was defined as a positive amniotic fluid culture for microorganisms or a positive polymerase chain reaction for Ureaplasma spp., and intra-amniotic inflammation was suspected when there was an elevated amniotic fluid white blood cell count (≥19 cells/mm³) or a positive rapid test for metalloproteinase-8 (sensitivity 10 ng/mL). For the purpose of this study, the "gold standard" for diagnosis of intra-amniotic inflammation was an elevated interleukin-6 concentration (>2.6 ng/mL) using an enzyme-linked immunosorbent assay. The results of amniotic fluid interleukin-6 were not available to managing clinicians. Follow-up amniocentesis was routinely offered to monitor the microbiologic and inflammatory status of the amniotic cavity and fetal lung maturity. Treatment success was defined as resolution of intra-amniotic infection/inflammation or delivery ≥34 weeks of gestation.

RESULTS

Of 22 patients with cervical insufficiency and intra-amniotic infection/inflammation, 3 (14%) had microorganisms in the amniotic fluid. Of the 22 patients, 6 (27%) delivered within 1 week of amniocentesis and the remaining 16 (73%) delivered more than 1 week after the diagnostic procedure. Among these, 12 had a repeat amniocentesis to assess the microbial and inflammatory status of the amniotic cavity; in 75% (9/12), there was objective evidence of resolution of intra-amniotic inflammation or intra-amniotic infection demonstrated by analysis of amniotic fluid at the time of the repeat amniocentesis. Of the 4 patients who did not have a follow-up amniocentesis, all delivered ≥34 weeks, 2 of them at term; thus, treatment success occurred in 59% (13/22) of cases.

CONCLUSION

In patients with cervical insufficiency and intra-amniotic infection/inflammation, administration of antibiotics (ceftriaxone, clarithromycin, and metronidazole) was followed by resolution of the intra-amniotic inflammatory process or intra-amniotic infection in 75% of patients and was associated with treatment success in about 60% of cases.

Vaginal progesterone is as effective as cervical cerclage to prevent preterm birth in women with a singleton gestation, previous spontaneous preterm birth, and a short cervix: updated indirect comparison meta-analysis

BACKGROUND

An indirect comparison meta-analysis published in 2013 reported that both vaginal progesterone and cerclage are equally efficacious for preventing preterm birth and adverse perinatal outcomes in women with a singleton gestation, previous spontaneous preterm birth, and a sonographic short cervix. The efficacy of vaginal progesterone has been challenged after publication of the OPPTIMUM study. However, this has been resolved by an individual patient-data meta-analysis (Am J Obstet Gynecol. 2018;218:161-180).

OBJECTIVE

To compare the efficacy of vaginal progesterone and cerclage in preventing preterm birth and adverse perinatal outcomes in women with a singleton gestation, previous spontaneous preterm birth, and a midtrimester sonographic short cervix.

DATA SOURCES

MEDLINE, EMBASE, LILACS, and CINAHL (from their inception to March 2018); Cochrane databases, bibliographies, and conference proceedings.

STUDY ELIGIBILITY CRITERIA

Randomized controlled trials comparing vaginal progesterone to placebo/no treatment or cerclage to no cerclage in women with a singleton gestation, previous spontaneous preterm birth, and a sonographic cervical length <25 mm.

STUDY APPRAISAL AND SYNTHESIS METHODS

Updated systematic review and adjusted indirect comparison meta-analysis of vaginal progesterone vs cerclage using placebo/no cerclage as the common comparator. The primary outcomes were preterm birth <35 weeks of gestation and perinatal mortality. Pooled relative risks (RRs) with 95% confidence intervals were calculated.

RESULTS

Five trials comparing vaginal progesterone vs placebo (265 women) and 5 comparing cerclage vs no cerclage (504 women) were included. Vaginal progesterone, compared to placebo, significantly reduced the risk of preterm birth <35 and <32 weeks of gestation, composite perinatal morbidity/mortality, neonatal sepsis, composite neonatal morbidity, and admission to the neonatal intensive care unit (RRs from 0.29 to 0.68). Cerclage, compared to no cerclage, significantly decreased the risk of preterm birth <37, <35, <32, and <28 weeks of gestation, composite perinatal morbidity/mortality, and birthweight <1500 g (RRs from 0.64 to 0.70). Adjusted indirect comparison meta-analyses did not show statistically significant differences between vaginal progesterone and cerclage in the reduction of preterm birth or adverse perinatal outcomes.

CONCLUSION

Vaginal progesterone and cerclage are equally effective for preventing preterm birth and improving perinatal outcomes in women with a singleton gestation, previous spontaneous preterm birth, and a midtrimester sonographic short cervix. The choice of treatment will depend on adverse events and cost-effectiveness of interventions and patient/physician's preferences.

Comparative Evaluation of Arabin Pessary and Cervical Cerclage for the Prevention of Preterm Labor in Asymptomatic Women with High Risk Factors

Objective: Preterm labor is one of the most significant obstetric problems associated with high rate of actual and long-term perinatal complications. Despite the creation of scoring systems, uterine activity monitoring, cervical ultrasound and several biochemical markers, the prediction and prevention of preterm labor is still a matter of concern. The aim of this study was to examine cervical findings for the prediction and the comparative use of Arabin pessary or cerclage for the prevention of preterm birth in asymptomatic women with high risk factors for preterm labor. Material and methods: The study group was composed of singleton pregnancies (spontaneously conceived) with high risk factors for preterm labor. Cervical length, dilatation of the internal cervical os and funneling, were estimated with transvaginal ultrasound during the first and the second trimesters of pregnancy. Results: Cervical funneling, during the second trimester of pregnancy, was the most significant factor for the prediction of preterm labor. The use of Arabin cervical pessary was found to be more effective than cerclage in the prolongation of pregnancy. Conclusion: In women at risk for preterm labor, the detection of cervical funneling in the second trimester of pregnancy may help to predict preterm labor and to apply the appropriate treatment for its prevention. Although the use of cervical pessary was found to be more effective than cerclage, more studies are needed to classify the effectiveness of different methods for such prevention.

Effects of cervical cerclage on cervical length and the impact of changes in cervical length on pregnancy prognosis

OBJECTIVE

To identify any cervix-related morphological and functional marker that can be correlated with pregnancy prognosis in patients who have undergone cerclage for cervical incompetence.

DESIGN

An observational and prospective study.

SETTING

Department of Obstetrics, Paulista School of Medicine - Federal University of São Paulo (UNIFESP-EPM).

METHODS

Patients with cervical incompetence who underwent cervical cerclage using a modified version of the McDonald procedure during or before the 22nd week of pregnancy. The patients were examined by transvaginal ultrasound in the preoperative period, the immediate postoperative period, and between 20 and 24 weeks, 24 weeks + 1 day and 28 weeks, and 28 weeks + 1 day and 32 weeks. Cervical length and the presence of funneling were evaluated during all examinations. Changes in cervical length, presence or absence of funneling, percent increase or decrease in cervical length, and cervical length of less than established values (.

Cerclage position, cervical length and preterm delivery in women undergoing ultrasound indicated cervical cerclage: A retrospective cohort study

Objective

The objectives were to assess whether anatomical location of ultrasound (USS) indicated cervical cerclage and/or the degree of cervical shortening (cervical length; CL) prior to and following cerclage affects the risk of preterm birth (PTB).

Method

A retrospective cohort study of 179 women receiving cerclage for short cervix (≤25mm) was performed. Demographic data, CL before and after cerclage insertion, height of cerclage (distance from external os) and gestation at delivery were collected. Relative risk (RR) and odds ratio (OR) of preterm delivery were calculated according to the anatomical location of the cerclage within the cervix and the CL before and after cerclage as categorical and continuous variables. Partition tree analysis was used to identify the threshold cerclage height that best predicts PTB.

Results

25% (n = 45) delivered <34 weeks and 36% (n = 65) delivered <37 weeks. Risk of PTB was greater with cerclage in the distal 10mm (RR2.37, 95% CI 1.45–3.87) or the distal half of a closed cervix (RR2.16, 95% CI 1.45–3.87). Increasing absolute cerclage height was associated with a reduction in PTB (OR 0.87, 95% CI 0.82–0.94). A cerclage height <14.5 mm best predicts PTB (70.8%). Increasing CL following cerclage was associated with a reduction in PTB (OR0.87, 95% CI 0.82–0.94). Conversely, the risk of PTB was increased where CL remained static or shortened further following cerclage (RR2.34, 95% CI 1.04–5.25).

Conclusion

The higher a cerclage was placed within a shortened cervix, the lower the subsequent odds of PTB. Women whose cerclage is placed in the distal 10mm of closed cervix or whose cervix fails to elongate subsequently, should remain under close surveillance as they have the highest risk of PTB.

Not transabdominal!

Preterm birth remains a major cause of perinatal morbidity and mortality. A short cervix is strongly associated with spontaneous preterm birth. Professional organizations support cervical length screening for singleton gestations with a prior spontaneous preterm birth and second-trimester cervical length measurements between 16-24 weeks. All interventions used to decrease the risk of preterm birth in women with a short cervix are based on clinical trials that used transvaginal cervical length measurement, but transabdominal ultrasound has been shown to correlate well with transvaginal measurement in some observational studies. Transvaginal cervical length measurement is more accurate and more reliably obtained than the transabdominal approach. Conversely, transabdominal ultrasound could have the advantage of ease of implementation and, in general, is perceived by patients to be associated with less discomfort. Currently, there is no randomized clinical study that compares head-to-head the effectiveness of transvaginal vs transabdominal ultrasound for preterm birth risk screening. This point/counterpoint article summarizes the pros and cons of the 2 ultrasound approaches and debates whether transvaginal ultrasound should be used exclusively or if transabdominal ultrasound can be incorporated in cervical length screening for prevention of preterm birth.