Evolution of Fetal Growth in Symptomatic Sars-Cov-2 Pregnancies.

INTRODUCTION: SARS-CoV-2 is a viral disease with potentially devastating effects. Observational studies of pregnant women infected with SARS-CoV-2 report an increased risk for FGR. This study utilizes data from a prospective SARS-CoV-2 registry in pregnancy, investigating the progression of fetuses to fetal growth restriction (FGR) at birth following maternal SARS-CoV-2 and evaluating the hypothesis of whether the percentage of SGA at birth is increased after maternal SARS-CoV-2 taking into account the time interval between infection and birth. MATERIALS & METHODS: CRONOS is a prospective German registry enrolling pregnant women with confirmed SARS-CoV-2 infection during their pregnancy. SARS-CoV-2 symptoms, pregnancy- and delivery-specific information were recorded. The data evaluated in this study range from March 2020 until August 2021. Women with SARS-CoV-2 were divided into three groups according to the time of infection/symptoms to delivery: Group I<2 weeks, Group II 2-4 weeks, and Group III>4 weeks. FGR was defined as estimated and/or birth weight<10% ile, appropriate for gestational age (AGA) was within 10 and 90%ile, and large for gestational age (LGA) was defined as fetal or neonatal weight>90%ile. RESULTS: Data for a total of 2,650 SARS-CoV-2-positive pregnant women were available. The analysis was restricted to symptomatic cases that delivered after 24+0 weeks of gestation. Excluding those cases with missing values for estimated fetal weight at time of infection and/or birth weight centile, 900 datasets remained for analyses. Group I consisted of 551 women, Group II of 112 women, and Group III of 237 women. The percentage of changes from AGA to FGR did not differ between groups. However, there was a significantly higher rate of large for gestational age (LGA) newborns at the time of birth compared to the time of SARS-CoV-2 infection in Group III (p=0.0024), respectively. CONCLUSION: FGR rates did not differ between symptomatic COVID infections occurring within 2 weeks and>4 weeks before birth. On the contrary, it presented a significant increase in LGA pregnancies in Group III. However, in this study population, an increase in the percentage of LGA may be attributed to pandemic measures and a reduction in daily activity.

Statement of the Obstetrics and Prenatal Medicine Working Group (AGG - Preterm Birth Section) on "Outpatient Management for Pregnant Women with Preterm Premature Rupture of Membranes (PPROM)".

Preterm premature rupture of membranes (PPROM) is one of the leading causes of perinatal morbidity and mortality. After a PPROM, more than 50% of pregnant women are delivered within 7 days. Fetal and maternal risks are primarily due to infection and inflammation, placental abruption, umbilical cord complications and preterm birth. Standard care usually consists of an expectant approach. Management includes the administration of antenatal steroids and antibiotic therapy. Patients with PPROM require close monitoring. The management of pregnant women with PPROM (inpatient vs. outpatient) is still the subject of controversial debate. The international guidelines also do not offer a clear stance. The statement presented here discusses the current state of knowledge.

Prediction of Preterm Birth with the Uterocervical Angle in Singleton Pregnancies Treated with a Cervical Pessary.

BACKGROUND: Cervical pessaries are an established therapy option for patients at risk for spontaneous preterm birth (sPTB). The uterocervical angle (UCA) remains a promising sPTB predictor. However, its clinical significance has yet to be described in patients treated with a pessary. METHODS: This study analyzed data of patients treated with a pessary because of cervical shortening in singleton pregnancies. The patients were divided into 2 groups according to transvaginal ultrasound findings: the funneling group (n = 68) and the no-funneling group (n = 42). Moreover, we analyzed patients within these prespecified groups according to the UCA < 95° and ≥ 95°. RESULTS: Delivery occurred significantly earlier in patients treated with a pessary and with a high UCA ≥ 95°(p = 0.006). The median gestational age at delivery in patients treated with a pessary and with no funneling and a UCA < 95° vs. ≥ 95° were 39.00 and 36.14 weeks, respectively (p = 0.005). In cases with funneling and a UCA < 95° vs. ≥ 95° the mean gestational age at delivery was 38.14 and 38.07 weeks respectively (p=1,00). There was a significant negative linear correlation between UCA and the gestational age at delivery in all patients (p = 0.04), which was even profound in the group without funneling (p = 0.0002). However, we found no significant correlation between cervical length and gestational age at delivery in all patients (p = 0.42) as well as in the group without funneling (p = 0.28). CONCLUSION: In spite of pessary treatment, patients with UCA ≥ 95° presented with a higher risk of sPTB compared to patients with UCA < 95°. This suggests that the UCA seems to be a better predictor of sPTB than the cervical length in patients receiving pessary treatment.

Cervical pessary to prevent preterm birth and poor neonatal outcome: An integrity meta-analysis of randomized controlled trials focusing on adherence to the European Medical Device Regulation.

BACKGROUND: Findings from randomized trials (RCTs) on cervical pessary treatment to prevent spontaneous preterm birth are inconsistent. OBJECTIVES: Our hypothesis suggests that adhering to the European Medical Device Regulation (MDR) and following the instructions for use are essential prerequisites for successful therapy. Conversely, the non-adherence to these guidelines will probably contribute to its failure. SEARCH STRATEGY AND SELECTION CRITERIA: Based on validated criteria from integrity assessments we performed a systematic review identifying 14 RCTs evaluating the effect of cervical pessaries. DATA COLLECTION AND ANALYSIS: We analyzed the implications of 14 criteria each accounting for 0-2 points of a score reflecting the clinical evaluation plan (CEP) as proposed by the MDR to evaluate the risk-benefit ratio of medical devices. MAIN RESULTS: Seven RCTs in each singleton and twin pregnancies (5193 "cases") were included, detecting a high heterogeneity within control groups (I2 = 85% and 87%, respectively, P < 0.01). The CEP score varied from 11 to 26 points for all studies. The most common reasons for low scores and potential data compromise were poor recruitment rates, no (completed) power analysis, and no pre-registration, but mainly non-adherence to technical, biological, and clinical equivalence to the instructions for use as required by the MDR. All trials with score values greater than 20 had applied audit procedures. Within this group we found significantly reduced rates of spontaneous preterm birth at less than 34 weeks within the pessary group in singleton (odds ratio 0.28; 95% confidence interval 0.12-0.65) and twin pregnancies (odds ratio 0.30; 95% confidence interval 0.13-0.67). Similarly, there was a significant reduction in the composite poor neonatal outcome in singleton (odds ratio 0.25; 95% confidence interval 0.10-0.61) and twin pregnancies (odds ratio 0.54; 95% confidence interval 0.35-0.82) after a pessary as compared with controls. CONCLUSION: Non-audited RCTs and meta-analyses mixing studies of different clinical quality as pre-defined by a CEP and the MDR pose the risk for erroneous conclusions.

The Arabin cervical pessary for the prevention of preterm birth in twin-to-twin transfusion syndrome treated by fetoscopic laser coagulation: a multicenter randomized controlled trial.

BACKGROUND: Miscarriage and preterm birth are leading causes of loss and disability in monochorionic twins after laser treatment of twin-twin transfusion syndrome. OBJECTIVE: This study aimed to investigate the use of cervical pessary to reduce preterm birth before 32 weeks of gestation in monochorionic diamniotic twin pregnancies after fetal surgery for twin-twin transfusion syndrome. STUDY DESIGN: In this open-label multicenter randomized trial, pregnant women carrying monochorionic diamniotic twins requiring fetoscopic laser coagulation for twin-twin transfusion syndrome were randomly assigned in a 1:1 ratio to pessary placement or conservative management. The primary outcome was birth before 32 weeks of gestation. The secondary outcomes were birth before 28, 30, 34, or 37 weeks of gestation; preterm premature rupture of membranes; fetal and neonatal survival; and a composite of maternal and neonatal complications. The estimated sample size was 364 patients, with 182 cases in each arm of the study. The analysis was performed according to the intention-to-treat principle. Moreover, 2 interim analyses were planned. RESULTS: The trial was stopped prematurely after the first planned interim analysis for futility. Overall, 137 women were included in the analysis, 67 in the pessary group and 70 in the conservative management group. Preterm birth before 32 weeks of gestation occurred in 27 of 67 women (40.3%) in the pessary group and in 25 of 70 women (35.7%) in the conservative management group (adjusted odds ratio, 1.19; 95% confidence interval, 0.58-2.47; P=.63). No differences between groups was observed in the rate of deliveries before 28, 30, 34, and 37 weeks of gestation. Overall survival to delivery was 91.2% (125/137) for at least 1 twin, and 70.8% (97/137) for both twins, with no difference between groups. Neonatal survival at 30 days was 76.5% (208/272). There was no difference between the groups in maternal or neonatal morbidity. CONCLUSION: In monochorionic diamniotic twin pregnancies requiring fetal therapy for twin-twin transfusion syndrome, routine use of cervical pessary did not reduce the rate of preterm birth before 32 weeks of gestation.

Correction: Prevention and Therapy of Preterm Birth. Guideline of the DGGG, OEGGG and SGGG (S2k-Level, AWMF Registry Number 015/025, September 2022) - Part 1 with Recommendations on the Epidemiology, Etiology, Prediction, Primary and Secondary Prevention of Preterm Birth.

[This corrects the article DOI: 10.1055/a-2044-0203.].

Correction: Prevention and Therapy of Preterm Birth. Guideline of the DGGG, OEGGG and SGGG (S2k Level, AWMF Registry Number 015/025, September 2022) - Part 2 with Recommendations on the Tertiary Prevention of Preterm Birth and on the Management of Preterm Premature Rupture of Membranes.

[This corrects the article DOI: 10.1055/a-2044-0345.].

Prevention and Therapy of Preterm Birth. Guideline of the DGGG, OEGGG and SGGG (S2k-Level, AWMF Registry Number 015/025, September 2022) - Part 1 with Recommendations on the Epidemiology, Etiology, Prediction, Primary and Secondary Prevention of Preterm Birth.

Aim This revised guideline was coordinated by the German Society for Gynecology and Obstetrics (DGGG), the Austrian Society for Gynecology and Obstetrics (OEGGG) and the Swiss Society for Gynecology and Obstetrics (SGGG). It aims to improve the prediction, prevention, and management of preterm birth, based on evidence from the current literature, the experience of members of the guidelines commission, and the viewpoint of self-help organizations. Methods The members of the contributing professional societies and organizations developed recommendations and statements based on international literature. The recommendations and statements were presented and adopted using a formal process (structured consensus conferences with neutral moderation, written Delphi vote). Recommendations Part 1 of this short version of the guideline presents statements and recommendations on the epidemiology, etiology, prediction, and primary and secondary prevention of preterm birth.

Prevention and Therapy of Preterm Birth. Guideline of the DGGG, OEGGG and SGGG (S2k Level, AWMF Registry Number 015/025, September 2022) - Part 2 with Recommendations on the Tertiary Prevention of Preterm Birth and on the Management of Preterm Premature Rupture of Membranes.

Aim The revision of this guideline was coordinated by the German Society for Gynecology and Obstetrics (DGGG), the Austrian Society for Gynecology and Obstetrics (OEGGG) and the Swiss Society for Gynecology and Obstetrics (SGGG). The aim of the guideline is to improve the prediction, prevention and management of preterm birth based on evidence from the current literature, the experience of members of the guidelines commission, and the viewpoint of self-help organizations. Methods The members of the contributing professional societies and organizations developed recommendations and statements based on international literature. The recommendations and statements were presented and adopted using a formal process (structured consensus conferences with neutral moderation, written Delphi vote). Recommendations Part 2 of this short version of the guideline presents statements and recommendations on the tertiary prevention of preterm birth and the management of preterm premature rupture of membranes.

A novel aspiration technique to assess cervical remodelling in patients with or without cervical shortening: Sequence of first changes, definition of cut-off values and impact of cervical pessary, stratified for cervical length.

BACKGROUND: The therapeutic significance of the cervical pessary has been confirmed by several studies. However, the underlying mechanism by which pessaries reduce the risk of a preterm birth remains elusive. The aim of this study is to investigate the hypothesis whether the application of a cervical pessary may stabilize the ectocervical stiffness in order to achieve a cervical arrest. METHODS: This is a prospective, controlled, non-interventional, post-market, monocentric, longitudinal, cohort study in a tertiary maternity hospital to determine ectocervical stiffness and its changes measured before and after placement of a pessary in singleton pregnancies with cervical shortening in the mid trimester. In order to assess reference values for cervical stiffness, we measured also singleton pregnancies with normal cervical length in the same gestational week spectrum. The cervical stiffness measured with the Pregnolia System as the Cervical Stiffness Index (CSI, in mbar) shall be the primary endpoint, whilst patient delivery data (gestational age, mode of delivery and complications) will be the secondary endpoint. In this pilot study, up to 142 subjects will be enrolled to have a total of 120 subjects (estimated dropout rate of 15%) to complete the study; pessary cohort: 60 (up to 71 recruited), control group: 60 (up to 71 recruited). DISCUSSION: Our hypothesis is that patients with cervical shortening will present with lower CSI values and that pessary placement will be able to stabilize the CSI values through further prevention of cervical remodelling. The measurement of controls with normal cervical length shall serve as a reference.

Effect of Teriparatide on Subsequent Fracture and Bone Mineral Density in 47 Women with Pregnancy- and Lactation-associated Osteoporosis and Vertebral Fractures.

Introduction Pregnancy- and lactation-associated osteoporosis (PLO) with predominantly vertebral fractures is a rare but severe disease which can occur in the last trimester of pregnancy or postpartum. The aim of the present study was to assess the impact of teriparatide on subsequent fractures and bone mineral density (BMD) in patients with PLO. Materials and Methods A total of 47 patients with PLO and postpartum spinal fractures (mean: 4 fractures) undergoing treatment with teriparatide were investigated. The data collection period was set between 2006 and 2018. All patients received a subcutaneous injection of 20 µg teriparatide once a day for 24 months as well as individually adapted vitamin D supplementation. After 24 months of treatment, all women received no further treatment and either had regular menstrual cycles or took oral contraceptives. Fractures were confirmed by X-ray or MRI. Changes in BMD from baseline were examined using serial DXA measurements. Results After 24 months of teriparatide treatment, we could demonstrate an increase in BMD at the lumbar spine, femoral neck and total hip of + 30.1%, + 11.7% and + 12.2% respectively (p < 0.001 for all). At 12 months after cessation of treatment, BMD remained stable compared to the 24-month measurements at the lumbar spine, femoral neck and total hip which showed non-significant changes of + 1.4%, + 2.6% and + 4.1% respectively. Out of the 47 patients with PLO with a mean of 4 existing fractures, 4 patients (7.8%) sustained a subsequent fracture, two after 3 - 5 months of treatment and two at > 6 months of treatment. Conclusion 24 months of treatment with teriparatide in women with PLO and multiple vertebral fractures significantly increased BMD, predominantly BMD of the spine. As patients were premenopausal, there was no significant decrease in BMD in the following 12 months after cessation of treatment.

Resuscitation of Term Compromised and Asphyctic Newborns: Better with Intact Umbilical Cord?

The authors hypothesize that particularly severely compromised and asphyctic term infants in need of resuscitation may benefit from delayed umbilical cord clamping (after several minutes). Although evidence is sparse, the underlying pathophysiological mechanisms support this assumption. For this review the authors have analyzed the available research. Based on these data they conclude that it may be unfavorable to immediately clamp the cord of asphyctic newborns (e.g., after shoulder dystocia) although recommended in current guidelines to provide quick neonatological support. Compression of the umbilical cord or thorax obstructs venous flow to the fetus more than arterial flow to the placenta. The fetus is consequently cut off from a supply of oxygenated, venous blood. This may cause not only hypoxemia and consecutive hypoxia during delivery but possibly also hypovolemia. Immediate cord clamping may aggravate the situation of the already compromised newborn, particularly if the cord is cut before the lungs are ventilated. By contrast, delayed cord clamping leads to fetoplacental transfusion of oxygenated venous blood, which may buffer an existing acidosis. Furthermore, it may enhance blood volume by up to 20%, leading to higher levels of various blood components, such as red and white blood cells, thrombocytes, mesenchymal stem cells, immunoglobulins, and iron. In addition, the resulting increase in pulmonary perfusion may compensate for an existing hypoxemia or hypoxia. Early cord clamping before lung perfusion reduces the preload of the left ventricle and hinders the establishment of sufficient circulation. Animal models and clinical trials support this opinion. The authors raise the question whether it would be better to resuscitate compromised newborns with intact umbilical cords. Obstetric and neonatal teams need to work even closer together to improve neonatal outcomes.

Maternal and neonatal outcomes of pregnancies with COVID-19 after medically assisted reproduction: results from the prospective COVID-19-Related Obstetrical and Neonatal Outcome Study.

BACKGROUND: Severe acute respiratory syndrome coronavirus type 2 infections in pregnancy have been associated with maternal morbidity, admission to intensive care, and adverse perinatal outcomes such as preterm birth, stillbirth, and hypertensive disorders of pregnancy. It is unclear whether medically assisted reproduction additionally affects maternal and neonatal outcomes in women with COVID-19. OBJECTIVE: To evaluate the effect of medically assisted reproduction on maternal and neonatal outcomes in women with COVID-19 in pregnancy. STUDY DESIGN: A total of 1485 women with COVID-19 registered in the COVID-19 Related Obstetric and Neonatal Outcome Study (a multicentric, prospective, observational cohort study) were included. The maternal and neonatal outcomes in 65 pregnancies achieved with medically assisted reproduction and in 1420 spontaneously conceived pregnancies were compared. We used univariate und multivariate (multinomial) logistic regressions to estimate the (un)adjusted odds ratios and 95% confidence intervals for adverse outcomes. RESULTS: The incidence of COVID-19-associated adverse outcomes (eg, pneumonia, admission to intensive care, and death) was not different in women after conceptions with COVID-19 than in women after medically assisted reproduction pregnancies. Yet, the risk of obstetrical and neonatal complications was higher in pregnancies achieved through medically assisted reproduction. However, medically assisted reproduction was not the primary risk factor for adverse maternal and neonatal outcomes including pregnancy-related hypertensive disorders, gestational diabetes mellitus, cervical insufficiency, peripartum hemorrhage, cesarean delivery, preterm birth, or admission to neonatal intensive care. Maternal age, multiple pregnancies, nulliparity, body mass index >30 (before pregnancy) and multiple gestation contributed differently to the increased risks of adverse pregnancy outcomes in women with COVID-19 independent of medically assisted reproduction. CONCLUSION: Although women with COVID-19 who conceived through fertility treatment experienced a higher incidence of adverse obstetrical and neonatal complications than women with spontaneous conceptions, medically assisted reproduction was not the primary risk factor.

Preterm Premature Rupture of Membranes - Inpatient Versus Outpatient Management: an Evidence-Based Review.

According to current guidelines, inpatient management until birth is considered standard in pregnant women with preterm premature rupture of membranes (PPROM). With the increasing burden on obstetric departments and the growing importance of satisfaction and right to self-determination in pregnant women, outpatient management in PPROM is a possible alternative to inpatient monitoring. The most important criterion for this approach is to ensure the safety of both the mother and the child. Due to the small number of cases (n = 116), two randomised controlled trials (RCTs) comparing inpatient and outpatient management were unable to draw any conclusions. By 2020, eight retrospective comparative studies (cohort/observational studies) yielded the following outcomes: no significant differences in the rate of maternal complications (e.g., chorioamnionitis, premature placental abruption, umbilical cord prolapse) and in neonatal morbidity, significantly prolonged latency period with higher gestational age at birth, higher birth weight of neonates, and significantly shorter length of stay of preterm infants in neonatal intensive care, shorter hospital stay of pregnant women, and lower treatment costs with outpatient management. Concerns regarding this approach are mainly related to unpredictable complications with the need for rapid obstetric interventions, which cannot be performed in time in an outpatient setting. Prerequisites for outpatient management are the compliance of the expectant mother, the adherence to strict selection criteria and the assurance of adequate monitoring at home. Future research should aim at more accurate risk assessment of obstetric complications through studies with higher case numbers and standardisation of outpatient management under evidence-based criteria.

Administration of Antenatal Corticosteroids: Current State of Knowledge.

The administration of a single course of corticosteroids before week 34 + 0 of gestation in cases with impending preterm birth is now standard procedure in obstetric care and firmly established in the guidelines of different countries. But despite the apparently convincing data, numerous aspects of this intervention have not yet been properly studied. It is still not clear which corticosteroid achieves the best results. There are very few studies on what constitutes an appropriate dose, circadian rhythms, the time frame in which corticosteroids are effective, and the balance between the risks and benefits of repeat administration. As the existing studies have rarely included patients before week 24 + 0 of gestation, we have very little information on the possible benefits of administering corticosteroids before this timepoint. If corticosteroids are administered antenatally after week 34 + 0 of gestation, the short-term benefit may be offset by the long-term adverse effect on psychomotor development. This present study summarizes the current state of knowledge regarding these issues.

Do obstetric units adhere to the evidence-based national guideline? A Germany-wide survey on the current practice of initial tocolysis.

OBJECTIVES: Current international guidelines recommend tocolytic treatment by at least 48 h to complete fetal lung maturation and to ensure in-utero transfer to a perinatal center before 34 weeks of gestation in patients with threatened preterm birth. According to the results of former surveys, significant differences between daily clinical practice patterns and evidence-based guideline recommendations regarding tocolytic treatment have been demonstrated. We compared data from a nation-wide survey on the practice of initial tocolysis with recommendations from the current German Guideline 015/025 "Prevention and Treatment of Preterm Birth". STUDY DESIGN: 632 obstetric units in Germany received a link to an online questionnaire between January 20th and March 31st 2020, which was developed according to national and international recommendations and guidelines. Collected data was descriptively analyzed by performing measures of frequency. RESULTS: The response rate was 19%; 51 (42.5%) of the respondents consider CTG tracing with ≥ 4 contractions within 20 min, 49 (40.8%) cervical length measurement of ≤ 25 mm and 13 (10.9%) subjective contractions as the most significant decision-making criteria for tocolysis; 47 (39.2%) of obstetric units initiate tocolysis earliest at 23 + 0, 34 (28.3%) at 22 + 0, 26 (21.7%) at 23 + 5 and 13 (10.8%) at 24 + 0 weeks of gestation; 104 (86.7%) stop tocolysis latest at the 34 + 0 weeks of gestation, 42 (35.0%) obstetric units administer antenatal corticosteroids at 23 + 5, 16 (13.3%) at 22 + 0, and 13 (10.8%) at 24 + 0 weeks of gestation. Calcium channel blockers are the first-line tocolytic drug used by 59 (49.1%) of the obstetric units, followed by intravenous betamimetics as bolus (n = 26, 21.7%) and atosiban (n = 20, 16.7%). Severe side-effects were observed by 105 (70%) of the respondents in association with the use of betamimetics, 14 (9.3%) with the use of nifedipine and 30 (20.0%) with nitroglycerine patches. The German guideline was considered the most important decision-making support by 78 (65%) of the obstetric units, followed by hospital specific SOPs/algorithms (n = 31, 25.8%). CONCLUSION: Our survey highlights a considerable discrepancy between evidence-based guideline recommendations and daily clinical practice.

The impact of funneling shape on the secondary prevention of spontaneous preterm birth in patients treated with either an Arabin pessary, McDonald cerclage or early total cervical occlusion (ETCO).

OBJECTIVE: Cervical funneling is associated with spontaneous preterm birth (sPTB). The aim of this analysis was to assess the relationship between funneling shape and the response to the McDonald cerclage, the Arabin pessary and the early total cervical occlusion (ETCO). METHODS: We retrospectively analyzed data of 312 randomly selected singleton pregnancies with cervical shortening <25 mm or normal cervical length and evaluated them according to the progression of funneling: control group (n = 46), cervical shortening without funneling (n = 107), V-shaped funneling (n = 68), U-shaped funneling (n = 47), and prolapse of the amniotic sac (n = 44). We evaluated sPTB rates <34, <28, <32, and <37 weeks as well as prolongation of gestation and birthweight. RESULTS: Regarding the rate of sPTB <34 weeks there was no statistical significance in either of the comparisons between control group and each of the four risk groups. Regarding prolongation of gestation we demonstrated a statistical significance for all risk groups compared to the control group (all p < .05) with the lowest prolongation rate noted in the group with amnion prolapse and the highest in the group with isolated cervical shortening without funneling. Similarly, progression of funnel shape resulted in an absolute decrease of birthweight for all risk groups compared to the control group, albeit not significant for the group with U-shaped funneling (p = .1058). CONCLUSION: Independent of the treatment, there was a significant impact of funneling shape on pregnancy duration and birthweight.

McDonald versus Shirodkar cervical cerclage for prevention of preterm birth: a systematic review and meta-analysis of pregnancy outcomes.

OBJECTIVE: To compare pregnancy outcomes of patients undergoing either McDonald or Shirodkar cervical cerclage. METHODS: PubMed, Web of Science, Scopus, and Google scholar were systematically searched up to June 2020. Inter-study heterogeneity was assessed using Cochrane's Q test and the I2 statistic. Data were pooled using the fixed- or random-effects model and expressed as relative risk (RR) or weighted mean difference (WMD) as appropriately. RESULTS: A total of eight observational studies, reporting data on 724 pregnancies, were included in this meta-analysis. As compared to the Shirodkar cerclage, the pooled findings showed that the gestational age at delivery (WMD = -1.95, 95% CI: -2.89 to -1.01, p < .001; I2 = 57.5%) and birth weight (WMD = -355.69, 95% CI: -413.76 to -297.62, p < .001; I2 = 28.8%) were significantly lower in McDonald cerclage. The risk of preterm premature rupture of the membranes (PPROM) (RR = 1.76; 95% CI: 1.14 - 2.71; I2 = 0.0%) and neonatal intensive care unit (NICU) admission (RR = 1.61; 95% CI: 1.09 - 2.39; I2 = 62.1%) were also higher for McDonald group. However, no significant difference was observed between both groups in terms of cesarean delivery and perinatal/neonatal death. CONCLUSION: McDonald cerclage is associated with a shorter duration of pregnancy, lower mean birth weight and increased risk of PPROM and NICU admission compared to the Shirodkar procedure.