Impact of Cervical Pessary Treatment for Prevention of Spontaneous Preterm Birth in Twin Pregnancies With Cervical Shortening on Children's Long-Term Survival Without Neurodevelopmental Disability: THE IMPETUS-TRIAL
Phase: NA
Conditions: Preterm Birth, Premature Birth
Sponsor: Bürgerhospital Frankfurt

 
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Code: IMPETUS-Trial 
 
 
 
Version 1.2 (January 2018) 
 
 
 
 
Impact of Cervical Pessary Treatment for Prevention of Preterm Birth in  
Twin Pregnancies with Cervical Shortening  
on children`s Long-Term Survival without Neurodevelopmental Disability 
THE IMPETUS-TRIAL 
 
 

 
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Summary 
 
 
Description: Clinical Trial with a sanitary device in its authorized using conditions. 
 
Title: Impact of Cervical Pessary Treatment for Prevention of Preterm Birth 
in Twin Pregnancies with Cervical Shortening on children`s  
Long-Term Survival without Neurodevelopmental Disability 
The IMPETUS-Trial 
 
 
 
Sponsor:  Bürgerhospital und Clementine Kinderhospital gGmbH, Frankfurt/M., 
Germany 
 
Coordinator of the study: PD Dr. med. Ioannis Kyvernitakis (Frankfurt/M., Germany) 
 
Main investigator of the study (Frankfurt/M.): PD Dr. med. Ioannis Kyvernitakis  
and PD Dr. med. Dr. med. habil. Franz Bahlmann 
 
Scientific assistance: Marita Wasenitz 
Statistical support and power analysis:  
Univ.-Prof. Dr. Eva Herrmann, Faculty of Medicine, Institute of Biostatistics and 
Mathematical Modelling, Goethe-University of Frankfurt 
Scientific expert support for neurodevelopmental questionnaires:  
PD Dr. med. Heike Philippi, Faculty of Medicine, University of Heidelberg 
 
 
Study Centres & Site investigators: 
  
International Centres 
• 
University of Adelaide, Australia 
Professor Ben Willem Mol, MD, PhD 
• 
Medical School of the Aristotle-University of Thessaloniki, Greece 
Professor Apostolos Athanasiadis, MD, PhD 
• 
University Hospital of Athens, Greece 
Professor George Daskalakis, MD, PhD 
• 
Vall d'Hebron University Hospital, Spain 
Professor Elena Carerras, MD, PhD  
  
German Centres 
• 
Vivantes Klinikum im Friedrichshain, Berlin, Germany 
Associate Professor Lars Hellmeyer, MD, PhD 
• 
Bürgerhospital Frankfurt, Germany 
Associate Professor Ioannis, Kyvernitakis, MD, PhD 
• 
Universitätsklinikum Frankfurt, Germany  
Professor Frank Louwen,MD, PhD, PhD h.c. so korrekt? 
• 
Asklepios Kliniken, Hamburg, Germany 
Associate Professor Holger Maul, MD, PhD 
• 
Universitätsklinikum des Saarlandes, Homburg, Germany 
Amr Hamza, MD, PhD 

 
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• 
Charité-Universitätsmedizin Berlin 
Jens H. Stupin, MD, PhD  
 
Reference 
Ethics 
Committee: Ethik-Kommission 
Landesärztekammer 
Hessen, 
Frankfurt/M., Germany 
 
Scientific Expert Panel at Bürgerhospital Frankfurt/M. 
 
• 
PD Dr. med. Dr. med. habil. Franz Bahlmann 
Head of the Department of Obstetrics and Gynecology 
Tel.: +4969 1500 412 / Fax +4969 1500 400  
f.bahlmann@buergerhospital-ffm.de 
 
Monitoring Data Committee:  
• 
Scientific Data Monitoring Committee 
Prof. Dr. med. Ben Willem Mol 
Full Professor of Obstetrics and Gynaecology, Robinson Research Institute, 
SAHMRI, University of Adelaide, Australia 
ben.mol@adelaide.edu.au. 
 
Scientific Advisory Board 
• 
Prof. Dr. Zarko Alfirevic 
Full Professor of Obstetrics and Gynecology 
Department of Women`s and Children´s Health, University of Liverpool, UK 
zarko@liv.ac.uk  
 
Sanitary device: The Arabin cervical pessary, which is CE-certified for preventing SPB 
(CE 0482 / EN ISO 13485: 2012 + AC:2012 annex III of the council directive 93/42 
EEC).  
 
Main objective: To assess the impact of placing a cervical pessary in twin 
pregnancies 
with 
cervical 
shortening 
on 
chlidren’s 
survival 
without 
neurodevelopmental disability at the age of 3.  
 
Study 
design: 
Prospective 
Open-label 
Multicentre 
International 
Collaborative 
Randomized Controlled Trial, in parallel groups, based on intention to treat comparing 
the placement of a cervical pessary with usual management in cases of twin 
pregnancies with cervical shortening   
 
Main outcome: Children`s survival without neurodevelopmental disability at the age of 
3 years. 
 
Study population: Women attending the reference hospital due to a dichorionic twin 
pregnancy with cervical shortening ≤ 25th percentile and fulfil the inclusion criteria the 
study will be proposed. The patients will be informed of the intended therapeutic 
effect and possible side effects. If they agree and after obtaining their informed 
consent, they will be randomised according to the respective gestational week to 
either usual management (=control group) or cervical pessary placement up to 37+0 
weeks (= pessary group). According to the gestational week and when the cervical 
shortening lies under the 25th percentile the patients are randomized to the following 
subgroups: gestational age in weeks 16-20, gestational age in weeks 20-24 and 
gestational age in weeks 24-28. 
 
 
Sample size:  

 
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A stratified design, which divides the sample among 3 strata according to week of 
gestation, is analysed using the two-sided, Chochran-Mantel-Haenzel test with a 
significance level of alpha=5%. Sample sizes, summed across all strata, of 250 in 
group 1 (pessary group) and 250 group 2 (control-group), overall 500, achieve 80% 
power to prove significant difference when the odds ratio is actually 2,29 
corresponding to the lower limit of a one-sided 90% confidence interval of the results 
in van´t Hooft (ProTwin Trial)12. 
To account for a drop out rate of 25%, overall n=672 pregnant women will be 
recruited. 
 
Study calendar:  
Starting recruitment: July 1st, 2018 
Finishing recruitment and follow-up: Dec 31st, 2023 
Final report: July 2024. 
 
 
Table of contents 
 
1. General Information 
 
1.1. Title, protocol identifying number and date. 
1.2. Name and address of the Sponsor. 
1.3. Name and title of the authorized person by the Sponsor to sign the protocol and 
the protocol amendments. 
1.4. Name, title, addresses and telephone numbers of the medical experts of the 
Sponsor of the trial. 
1.5. Name and title of all the researchers who are responsible for conducting the trial 
and address and telephone numbers of trial sites. 
1.6. Name, title, address and telephone number of the qualified physician who is 
responsible for all medical decisions on each trial site. 
1.7. Name and address of the medical departments or institutions that are involved in 
the trial. 
 
2. Rationale 
 
2.1. Justification of the relevance of the trial. 
2.2. Description of the study population. 
2.3. Name and description of the device under investigation. 
2.4. Statement that testing will be performed according to the protocol, GCP and 
applicable legal requirements. 
 
3. Objective 
 
4. Design 
 
4.1. Specific description of primary and secondary variables. 
4.1.1. Primary outcome. 
4.1.2. Secondary outcomes. 
4.2. Description of the trial design. 
4.3. Flowchart. 
4.4. Description of the medical device and treatment regimen. 
4.5. Expected duration of subject’s participation. 
4.6. Completion and interruption criteria of the study or the subjects. 
4.7. Maintenance of the randomization codes and test procedures of the trial. 

 
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4.8. Identification of data to be collected in the case report file (CRF) that should be 
considered as data source. 
4.9. Definition of what is considered to be the end of the study. 
 
5. Selection and withdrawal of subjects 
 
5.1. Inclusion criteria. 
5.2. Exclusion criteria. 
5.3. Withdrawal criteria. 
5.4. Rescue treatment criteria. 
 
6. Treatment of Subjects 
 
6.1. Treatments to be administered. 
 
 
 
7. Efficacy assessment 
 
7.1. Specification of efficacy parameters: Primary and secondary endpoints. 
7.2. Methods and timing to assess, record and analyze the efficacy parameters. 
 
8. Assessment of Safety 
 
8.1. Procedures to record and report adverse events. 
8.2. Definitions. 
8.3. Procedures for immediate notification of serious or unexpected adverse events. 
 
9. Statistics 
 
9.1. Description of statistical methods. 
9.2. Expected number of subjects to be included. 
9.3. Criteria for termination of the trial. 
9.4. Selection of subjects to be included in each analysis. 
 
10. Direct Access to Data Source 
 
11. Quality and Control Assurance 
 
12. Ethical issues 
 
13. Data Management and Registry file 
 
14. Funds and Insurance 
 
15. Publication Policy 
 
16. Legal Issues 
 
17. References 
 
18. Annex 
 

 
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1. General information 
 
1.1. Title, protocol identifying number and date. 
 
Impact of Cervical Pessary Treatment for Prevention of Preterm Birth in Twin 
Pregnancies with Cervical Shortening on Children´s Long-Term Survival without 
Neurodevelopmental Disability 
Code: The Impetus-Trial 
Version and date: version 1.2 (January 2018) 
 
1.2. Name and address of the Sponsor. 
 
Bürgerhospital und Clementine Kinderhospital Frankfurt gGmbH  
CEO Wolfgang Heyl 
Nibelungenallee 37-41, 60318 Frankfurt am Main 
 
1.3. Name and title of the authorised person by the Sponsor to sign the protocol 
and the protocol amendments. 
 
PD Dr. med. Ioannis Kyvernitakis 
Consultant at Department of Obstetrics and Gynecology 
Bürgerhospital, and Clementine Kinderhospital gGmbH Frankfurt/M., Germany 
 
1.4. Name, title, addresses and telephone numbers of the medical experts of the 
Sponsor of the trial.  
 
o PD Dr. med. Dr. med. habil. Franz Bahlmann 
Head of the Department of Obstetrics and Gynecology 
Tel.: +4969 1500 412 / Fax +4969 1500 400  
Email: f.bahlmann@buergerhospital-ffm.de 
 
o PD Dr. med. Ioannis Kyvernitakis 
Consultant at Department of Obstetrics and Gynecology 
Tel: +4969 1500 5807 / Fax +4969 1500 400 
Email: i.kyvernitakis@buergerhospital-ffm.de 
And janniskyvernitakis@gmail.com 
 
Bürgerhospital Frankfurt/M.  
Nibelungenallee 37-41 
60318 Frankfurt am Main, Germany 
 
 
1.5. Name and title of all the researchers who are responsible for conducting the 
trial and address and telephone numbers of the trial sites.  
 
PD Dr Franz Bahlmann. Head of Obstetrics Department. 
PD Dr. Ioannis Kyvernitakis. Consultant at Obstetrics Department. 
 
Bürgerhospital Frankfurt/M.  
Nibelungenallee 37-41 
60318 Frankfurt am Main, Germany 
Tel: +49 69 1500 412 / Fax +49 69 1500 4000 
 

 
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Other centres that will participate on the trial: 
 
International Centres 
o University of Adelaide, Australia 
Professor Ben Willem Mol, MD, PhD 
Tel.: +61 4 3412 2170 
ben.mol@adelaide.edu.au 
o Medical School of the Aristotle-University of Thessaloniki, Greece 
Professor Apostolos Athanasiadis, MD, PhD 
Department of Obstetrics and maternal fetal medicine 
Tel: +30 6944 315785 
apostolos3435@gmail.com 
o University Hospital of Athens, Greece 
Professor George Daskalakis, MD, PhD 
Department of Obstetrics and Gynecology 
Tel.: +30 694 5235757 
gdaskalakis@yahoo.com 
o Vall d'Hebron University Hospital, Spain 
Professor Elena Carerras, MD, PhD  
Department of Obstetrics and Gynecology 
ecarreras@vhebron.net  
Vall d'Hebron University Hospital, Passeig de la Vall d'Hebron 119-129,  
08035 Barcelona 
Tel.:+34 934 89 30 00 
  
German Centres 
o Vivantes Klinikum im Friedrichshain, Berlin 
Associate Professor Lars Hellmeyer, MD, PhD 
Head of Department of Obstetrics and Gynecology  
Email: Lars.Hellmeyer@vivantes.de  
Vivantes Klinikum im Friedrichshain, Landsberger Allee 49, 10249 Berlin,  
Tel.: +49 30 130 23 1442 
o Universitätsklinikum Frankfurt  
Professor Frank Louwen,MD, PhD, PhD h.c. 
Head of Department of Obstetrics and Perinatology 
Mail: Louwen@em.uni-frankfurt.de  
Universitätsklinikum Frankfurt, Theodor-Stern-Kai 7 
60590 Frankfurt am Main 
Tel: +49 69 6301 7703 
o Asklepios Kliniken, Hamburg 
Associate Professor Holger Maul, MD, PhD 
Head of Department of Obstetrics and Gynecology  
Mail: h.maul@asklepios.com 
Asklepios Krankenhaus Barmbek, 22087 Hamburg 
Tel: +49 40 2546 662 
o Universitätsklinikum des Saarlandes, Homburg 
Amr Hamza, MD, PhD 
Senior Consultant of Department of Obstetrics and Gynecology  
Mail: amr.hamza@uks.eu  
Universitätsklinikum des Saarlandes, Kirrbergerstr. 100, 66424 Homburg 
Tel: +49 6841 16 28000 
o Charite-Universitätsmedizin Berlin 
Jens H. Stupin, MD, PhD  

 
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Department of Obstetrics and Gynecology 
jens.stupin@charite.de  
Charité – Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin  
Tel: +49 30 450 – 50 
 
 
1.6. Name, title, address and telephone number of the qualified physician who is 
responsible for all medical decisions on each trial site. 
 
International Centres 
o Professor Ben Willem Mol, MD, PhD 
Tel.: +61 4 3412 2170 
ben.mol@adelaide.edu.au 
University of Adelaide, Australia 
o Professor Apostolos Athanasiadis, MD, PhD 
Tel: +30 6944 315785 
apostolos3435@gmail.com  
Medical School of the Aristotle-University of Thessaloniki, Greece 
Department of Obstetrics and maternal fetal medicine 
o Professor George Daskalakis, MD, PhD 
Tel.: +30 694 5235757 
gdaskalakis@yahoo.com 
University Hospital of Athens, Greece  
Department of Obstetrics and Gynecology 
o Professor Elena Carerras, MD, PhD  
Tel.:+34 934 89 30 00 
ecarreras@vhebron.net  
Vall d'Hebron University Hospital, Passeig de la Vall d'Hebron 119-129,  
08035 Barcelona 
Department of Obstetrics and Gynecology 
 
German Centres 
o Associate Professor Lars Hellmeyer, MD, PhD 
Tel.: +49 30 130 23 1442 
Email: Lars.Hellmeyer@vivantes.de  
Vivantes Klinikum im Friedrichshain, Landsberger Allee 49, 10249 Berlin 
Head of Department of Obstetrics and Gynecology  
o Associate Professor Ioannis, Kyvernitakis, MD, PhD 
Mail: I.Kyvernitakis@buergerhospital-ffm.de 
Tel: +49 69 1500 5807 
Bürgerhospital Frankfurt/M, Nibelungenallee 37-41, 60318 Frankfurt am Main 
Consultant at Department of Obstetrics and Gynecology 
o Professor Frank Louwen,MD, PhD, PhD h.c.  
Tel: +49 69 6301 7703 
Mail: Louwen@em.uni-frankfurt.de  
Universitätsklinikum Frankfurt, Theodor-Stern-Kai 7 
60590 Frankfurt am Main 
Head of Department of Obstetrics and Perinatology 
o Associate Professor Holger Maul, MD, PhD 
Tel: +49 40 2546 662 
Mail: h.maul@asklepios.com 
Asklepios Krankenhaus Barmbek, 22087 Hamburg, 
Head of Department of Obstetrics and Gynecology  

 
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o Universitätsklinikum des Saarlandes, Homburg 
Amr Hamza, MD, PhD 
Tel: +49 6841 16 28000 
Mail: amr.hamza@uks.eu 
Universitätsklinikum des Saarlandes, Kirrbergerstr. 100, 66424 Homburg 
Senior Consultant of Department of Obstetrics and Gynecology  
o Jens H. Stupin, MD, PhD  
Tel: +49 30 450 – 50 
jens.stupin@charite.de  
Charité – Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin  
Department of Obstetrics and Gynecology 
 
 
1.7. Name and address of the medical departments or institutions that are 
involved in the trial.  
 
Department of Obstetrics and Gynecology international Centres: 
o University of Adelaide, Adelaide, Australia 
o Medical School of the Aristotle-University of Thessaloniki, Thessaloniki, 
Greece 
o University Hospital of Athens, Athens, Greece  
o Vall d'Hebron University Hospital, Barcelona, Spain 
 
Department of Obstetrics and Gynecology in Germany: 
o Bürgerhospital Frankfurt/M, Nibelungenallee 37-41, 60318 Frankfurt am Main. 
o Kath. Marien Krankenhaus GmbH, Alfredstr. 9, 22087 Hamburg. 
o Vivantes Klinikum im Friedrichshain, Landsberger Allee 49, 10249 Berlin. 
o Universitätsklinikum des Saarlandes, Kirrbergerstr. 100, 66424 Homburg.  
o Charité – Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin  
o Universitätsklinikum Frankfurt, Theodor-Stern-Kai 7, 60590 Frankfurt am Main 
 
 
2. Rationale 
 
2.1. Justification of the relevance of the trial. 
Preterm birth (PTB) is a major contributing factor to perinatal morbidity and mortality. 
Prematurity requires intensive medical care for the neonate and is associated with an 
increased risk of mortality, disability, and developmental disorders later in life.1,2 
Women with a twin pregnancy are at increased risk of preterm delivery. In the 
Netherlands, approximately 50% of women with a multiple pregnancy deliver before 
37 weeks’ gestation, of whom 9% deliver before 32 weeks.3 Also for the USA the rate 
of preterm birth was as high as 56.6% in twins and the preterm delivery rate before 
32 weeks was 11.3%.4  
A short cervix (<25 mm) is associated with early and very early preterm birth in twins, 
and 15% of women with twin gestations have a cervix ≤ 25 mm.5 This measurement 
has become the method of choice for screening asymptomatic pregnant women at 
risk for preterm birth<24 weeks of gestation both in twin and singleton pregnancies 6 
A cervical pessary to support the cervix in pregnant women with cervical insufficiency 
was introduced in 1960. A cervical pessary is a silicone ring with a smaller diameter 
to be fitted around the cervix and a larger diameter to fix the device against the pelvic 
floor. This effectively rotates the cervix toward the posterior vaginal wall and corrects 
the cervical angle.7 
In a prospective randomised trial the “ProTwin Trial” 8 813 women with twin 
pregnancies at a gestational age of 16 weeks to 20 weeks were randomised to either 

 
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pessary treatment or expectant management. Subgroup analysis of women with a 
shortened cervix below the 25 percentile (=38 mm) showed for the pessary group a 
significant 6-fold decrease in perinatal mortality and a reduction of severe morbidity.  
This demonstrates that an early screening followed by an early intervention is 
essential for patients at-risk. A secondary analysis “per protocol“ of the ProTwinTrial 
revealed that the success of pessary treatment was mostly dependent on the correct 
placement and the duration of the therapy 9. 
A further prospective-randomised trial by Goya et. al 10 also proved a significant 
reduction of the preterm delivery rate in twin pregnancies with cervical shortening 
(<25 mm, 20-24 weeks of gestation) after placement of a pessary compared to 
expectant management; the reduction in mortality was less pronounced than in the 
ProTwin Trial. A new case-control-trial by Fox et al. 11 showed a decrease in early 
preterm birth before 32 weeks of gestation (4.8% vs. 28.6%, P=.05), a considerable 
prolongation of pregnancy (65.2 d. vs. 52.1 d, P=.025) and a reduced neonetal 
morbidity (9.5% vs. 34.9%, P=.04) in twin pregnacies after pessary therapy.  
A secondary analysis of the ProTwin Trial indicated a higher survival rate without 
neurodevelomental disability in the long-term outcome 3 years after pessary 
treatment (92.4 vs. 73.8%, p=0.006) compared to expectant management 12. 
A prospective, randomised controlled trial by Nikolaides 13 and a cohort study by 
Monfrance 14 in twin pregnancies with short cervix showed no significant effect of the 
pessary therapy compared to expectant management. 
Up to now there is just one Cochrane review available concerning pessary therapy 
and the authors concluded that in spite of the posive effects seen that more trials 
should be conducted 15. 
 
 
2.2. Description of the study population. 
 
Women attending the reference hospital due to cervical shortening in twin 
pregnancies and fulfil the entry criteria (dichorionic twin pregnancy with cervical 
shortening ≤ 25th percentile and do not fulfil the exclusion criteria), the study will be 
proposed. The patients will be informed of the intended therapeutic effect and 
possible side effects. If they agree and after obtaining their informed consent, they 
will be randomised according to the respective gestational week to either usual 
management (=control group) or cervical pessary placement up to 37 weeks (= 
pessary group). According to the gestational week and when the cervical shortening 
is under the 25th percentile the patients will be randomized to the following 
subgroups: gestational age in weeks 16-20, gestational age in weeks 20-24 and 
gestational age in weeks 24-28. 
Specifically, the 25th centile of cervical length is defined at 32 mm, 30 mm and 28 mm 
for the 16+0 – 19+6, 20+0 – 23+6 and 24+0 – 28+0 weeks of gestation respectively. 
2.3. Name and description of the device under investigation.  
 
The Arabin cervical pessary, which is CE-certified for preventing SPB (CE 0482 / EN 
ISO 13485: 2012 + AC:2012 annex III of the council directive 93/42 EEC).  
See annex I. 
2.4. Statement that testing will be performed according to protocol, GCP and 
applicable legal requirements. 
 
The Clinical Trial will be conducted following the protocol, the GCP, and all legal 
requirements. 
 
 

 
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3. Objective 
 
This study aims to investigate the benefit of placing a cervical pessary in comparison 
to the expectant standard management in dichorionic twin pregnancies with cervical 
shortening ≤ 25 percentile in terms of long-term survival without neurodevelopmental 
disability of the children. 
Hereby, a standardized validated test called ‘Ages and Stages 3rd edition’ should 
evaluate the children’s neurodevelopment at the age of 3 years. The test can be 
conducted by the parents and takes approximately 12 minutes. The questionnaires 
will be provided by the sponsor. 
 
 
 
4. Design 
 
4.1. Specific description of primary and secondary variables. 
 
4.1.1. Primary outcome: 
 
o Children`s survival without neurodevelopmental disability at the age of 3. 
 
4.1.2. Secondary outcomes:  
o Offspring 
• 
Time to birth 
• 
Preterm birth before 37 weeks: rate of delivery before 36+6 weeks  
• 
Preterm birth before 34 weeks: rate of delivery before 33+6 weeks  
• 
Preterm birth before 32 weeks: rate of delivery before 31+6 weeks  
• 
Preterm birth before 30 weeks: rate of delivery before 29+6 weeks  
• 
Preterm birth before 28 weeks: rate of delivery before 27+6 weeks  
• 
Birth weight: median weight (g) of the newborns at birth 
• 
Fetal or neonatal death: rate of intrauterine demise or neonatal death 
during the first 24 hours 
• 
Neonatal morbidity: rate of major adverse neonatal outcomes before 
discharge from the hospital 
▪ 
Intraventricular Haemorrhage (IVH): grades III-IV 
▪ 
Retinopathy of prematurity 
▪ 
Respiratory Distress Syndrome (RDS): grades II-IV, 
▪ 
Need for ventilation > 72 h 
▪ 
Necrotising enterocolitis 
▪ 
Proven or suspected sepsis, antibiotics (>5 days) 
▪ 
Need (Duration in days) for neonatal special care (NICU)  
• 
Harm from intervention 
 
o Mother: 
• 
Maternal death 
• 
Significant maternal adverse events (rate): 
▪ 
Heavy bleeding: bleeding that requires a medical intervention 
▪ 
Cervical tear: cervical rupture due to the pessary placement 
▪ 
Uterine rupture: rupture of the uterus due to contractions or 
surgery 
• 
Physical or psychological intolerance to pessary: discomfort or pain due to 
the pessary that makes daily life uncomfortable (number of cases) 
• 
Rupture of membranes before 32 weeks: rate of rupture of amniotic 
membranes before 31+6 weeks 

 
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• 
Infection/inflammation  
• 
Hospitalisation for threatened preterm labour before 32 weeks: 
requirement of hospitalisation due to preterm contractions that need 
medical treatment to try to stop them before 31+6 weeks (rate) 
▪ 
Mean hospital stay duration: number of days of admittance at the 
hospital 
▪ 
Use of tocolytic treatment: Type of tocolytic, days of treatment, 
dose 
 
4.2. Description of the trial design. 
 
Open Multicentre International Collaborative Randomized Controlled Trial, in parallel 
groups, based on intention-to-treat analysis comparing the placement of a prophylactic 
cervical pessary with usual management in twin pregnancies with shortened cervix ≤ 25 
percentile  
 
4.3. Flowchart. 
 
 
 
 

 
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4.4. Description of the medical device and the treatment regimen. 
 
The cervical pessary is a vaginal device (silicone ring) that is used to treat pregnant 
women for preventing spontaneous preterm birth. This device can be easily placed 
around the uterine cervix without pain (see annex I). 
If a woman with a dichorionic twin pregnancy at a gestational age of 16 weeks up to 
28 weeks is diagnosed with a shortened cervix ≤ 25 percentile during a preventive 
examination in pregnancy her vaginal pH-value is checked to preclude a vaginal 
infection. If her pH-value is < 4,4 she will be informed about the ongoing trial. If she is 
willing to participate and gives her informed consent, the woman will be randomized 
according to her respective gestational age to either pessary treatment group or 
expectant management group. 
 
If the pregnant woman is assigned to the pessary group the pessary will be inserted 
directly. This procedure does not need anaesthesia and it does not need to be done 
in a surgery room. After the insertion of the pessary the correct fit of the pessary is 
verified by transvaginal ultrasound and in case it does not fit perfectly, it can easily be 
adjusted. The pessary will be removed at 37 weeks of gestation, or before if any 
unexpected event occurs (see 4.6).  
After insertion of the pessary the obstetrical management during the pregnancy will 
be the same in both groups. Further surveillance of the pregnancy will not be 
influenced by the participation on the study. 
 
 
 4.5. Expected duration of subject’s participation. 
 
Study calendar:  
Starting recruitment: July 1st, 2018 
Finishing recruitment and follow-up: Dec 31st, 2023 
Final report: July 2024. 
 
 

 
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4.6. Completion and interruption criteria of the study or the subjects. 
 
The pessary will be removed at 37+0 weeks of pregnancy. The indications to remove 
them before this time will be: active bleeding stronger than usual period bleeding, 
persistent contractions after tocolysis and premature rupture of the membranes after 
34 weeks. 
After removing the pessary, the obstetrical management will be done as usual and 
will not be influenced by the study. 
 
4.7. Maintenance of the randomisation codes and test procedures of the trial. 
 
Every participating centre will have its own randomisation list.  
We have created a database in a website so it can be accessed worldwide, that 
every hospital will be able to randomize their patients.  
Every center will receive a password and a username in order to access the 
database for recruitment, randomization and documentation of patient data. Hereby, 
a personal identification number will be assigned for every patient. Patient names will 
not appear in the databases.  
This database will be supervised and coordinated by PD Dr. Ioannis Kyvernitakis, 
Bürgerhospital Frankfurt/M. (Webmaster). 
 
4.8. Identification of data to be collected in the case report files (CRF) that 
should be considered as data source. 
 
Data will be collected in E-CRF, provided by >Dr. Olaf Hars Wissenschaft, Berlin< on 
study software “Castor”. 
 
4.9. Definition of what is considered to be the end of the study. 
 
The study will be finished after the 3 year-follow up examination concerning 
neurodevelopmental disabilities, which will be conducted on the surviving children of 
the participating patients.  
 
 
 
5. Selection and withdrawal of subjects 
5.1. Inclusion criteria. 
 
o Dichorionic diamnionic twin pregnancy with  
o 16-28 weeks of gestation 
o Minimal age of 18 years 
o Informed consent signature 
5.2. Exclusion criteria. 
 
o Monochorionic twin pregnancy 
o Major fetal abnormalities (requiring surgery or leading to infant death or severe 
handicap) 
o Cerclage prior to randomisation 
o Uterine malformation 
o Placenta previa totalis 
o Active vaginal bleeding at the moment of randomization 
o Spontaneous rupture of membranes at the time of randomization 
o Silicone allergy 

 
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o Current participation in other RCT 
o Painful regular uterine contractions 
 
5.3. Withdrawal criteria. 
 
If a participant may voluntarily withdraw from treatment or if it is necessary to remove 
the pessary due to the conditions described before, the patients will be followed as 
usual until delivery (intention-to-treat analysis).  
The death of one twin is not an exclusion criterion for the pessary placement. 
The replacement of patients is not applicable in this trial. 
 
5.4. Rescue treatment criteria.  
 
If the cervical length decreases later on during the pregnancy, the management of 
the pregnancy in each centre will be the usual. 
In case of secondary cervical shortening in the follow-up period pessary treatment 
may be offered as a rescue treatment up to 32+0 weeks of gestation. 
Cervical cerclage or progesterone are generally not indicated in twin pregnancies. 
 
6. Treatment of Subjects 
6.1. Treatments to be administered. 
 
The pessary will be inserted during a preventive examination in pregnancy in the 
examination room. This procedure does not need anaesthesia and it does not need 
to be done in a surgery room. After the insertion of the pessary the correct fit of the 
pessary is verified by transvaginal ultrasound and in case it does not fit perfectly, it 
can easily be adjusted. The pessary will be removed at 37+0 weeks of gestation, or 
before if any unexpected event occurs (see 4.6).  
After insertion of the pessary the obstetrical management during the pregnancy will 
be the same in both groups. Further surveillance of the pregnancy will not be 
influenced by the participation on the study. 
 
 
7. Efficacy assessment 
 
7.1. Specification of efficacy parameters: Primary and secondary endpoints. 
 
This study aims to investigate the benefit of placing a prophylactic cervical pessary in 
comparison to the usual management in twin pregnancies with cervical shortening ≤ 
25 percentile in terms of long-term survival without neurodevelopmental disability of 
the children. 
 
 
7.2. Methods and timing to assess records and analyze the efficacy 
parameters. 
 
The patients will be assessed according to usual management in a twin pregnancy. 
 
 
 
Regular 
preventive exam  
Regular 
preventive exam  
Postnatal  
evaluation 
3 years follow up 
(corrected age) 
 
Study procedure 
study inclusion 
 
 
 
Informed consent 
x 
 
 
 

 
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Randomisation 
x 
 
 
 
Pessary placement 
x 
 
 
 
Pessary removal 
 
 
x 
at 37 WoG 
 
 
physical exams 
 
 
 
 
Abdominal US 
x 
x 
 
 
Vaginal US 
x 
Cervical lenght  
≤ 25 percentile 
 
 
 
pH-Value 
pH < 4,4 
 
 
 
Neonatal Examination 
 
 
x 
 
Ages and stages test 
 
 
 
x 
Exam at paediatrician 
 
 
 
x 
 
 
 
8. Assessment of Safety 
8.1. Procedures to record and report adverse events. 
 
If a serious and unexpected adverse effect occurs during pessary treatment, it will be 
notified to the study Sponsor. The Department of Obstetrics and Gynecology of the 
Sponsor will fill the side effects document to notify it to the Landesärztekammer 
Hessen. 
The patient affected by the adverse effect will be followed more intensively during the 
first days and if nothing else occurs, she will return to the standard control. 
 
8.2. Definitions. 
 
Adverse Event (AE): Any untoward medical occurrence in a patient or clinical 
investigation participants administered a medicinal product, which does not necessarily 
have to have a causal relationship with this treatment (the study medication). An AE 
can therefore be any unfavourable and unintended sign (including an abnormal 
laboratory finding), symptom or disease temporally associated with the use of the study 
medication/procedure, whether or not considered related to the study medication. 
 
Adverse Reaction (AR): All untoward and unintended responses to a medicinal product 
related to any dose. The phrase "responses to a medicinal product" means that a 
causal relationship between a study medication and an AE is at least a reasonable 
possibility, i.e., the relationship cannot be ruled out. 
All cases judged by either the reporting medically qualified professional or the sponsor 
as having a reasonable suspected causal relationship to the study medication / 
procedure qualify as adverse reactions. 
 
Serious Adverse Event (SAE): A serious adverse event is any untoward medical 
occurrence that at any dose: Results in death; is life-threatening, NOTE: The term "life-
threatening" in the definition of "serious" refers to an event in which the participant was 
at risk of death at the time of the event; it does not refer to an event which 
hypothetically might have caused death if it were more severe; Requires inpatient 
hospitalization or prolongation of existing hospitalization; Results in persistent or 
significant disability/incapacity, or is a congenital anomaly/birth defect. 
 
Other important medical events: Other events that may not result in death, are not life 
threatening, or do not require hospitalization, may be considered a serious adverse 
event when, based upon appropriate medical judgment, the event may jeopardize the 
patient and may require medical or surgical intervention to prevent one of the 
outcomes listed above. 

 
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To ensure no confusion or misunderstanding of the difference between the terms 
"serious" and "severe", which are not synonymous, the following note of clarification is 
provided: 
The term "severe" is often used to describe the intensity (severity) of a specific event 
(as in mild, moderate, or severe myocardial infarction); the event itself, however, may 
be of relatively minor medical significance (such as severe headache).  This is not the 
same as "serious," which is based on patient/event outcome or action criteria usually 
associated with events that pose a threat to a participant's life or functioning as defined 
in the bullet points above. Seriousness (not severity) serves as a guide for defining 
regulatory reporting obligations. 
 
Serious Adverse Reaction (SAR): An adverse event (expected or unexpected) that is 
both serious and, in the opinion of the reporting investigator, believed with reasonable 
probability to be due to one of the study treatments, based on the information provided. 
 
Suspected Unexpected Serious Adverse Reaction: A serious adverse reaction, the 
nature or severity of which is not consistent with the applicable product information 
(e.g. Investigator’s Brochure for an unapproved investigational product or summary of 
product characteristics for an approved product). 
 
8.3. Procedures for immediate notification of serious or unexpected adverse 
events.  
 
All AEs occurring during the study /or observed by the investigator or reported by the 
participant, whether or not attributed to study medication, will be recorded on the CRF. 
The following information will be recorded: description, date of onset and end date, 
severity, and assessment of relatedness to study medication, other suspect drug or 
device and action taken. Follow-up information should be provided as necessary.  
AEs considered related to the sanitary device, as judged by a medically qualified 
investigator, will be followed until resolution or the event is considered stable. All 
related AEs that result in a participant’s withdrawal from the study or are present at the 
end of the study, should be followed up until a satisfactory resolution occurs. 
It will be left to the investigator’s clinical judgment whether or not an AE is of sufficient 
severity to require the participant’s removal from treatment. A participant may also 
voluntarily withdraw from treatment due to what he or she perceives as an intolerable 
AE. If either of these occurs, the participant must undergo an end of study assessment 
and be given appropriate care under medical supervision until symptoms cease or the 
condition becomes stable. 
A medically qualified investigator will assess the relationship of AEs to the study 
medication. 
 
All SAEs must be reported to the main investigator. He will perform an initial check of 
the report, request any additional information, and he will notify it to the Ethics 
Committee. All SAE information will be recorded. It may be appropriate that some 
SAEs do not require immediate reporting but this must be justified. Justification might 
be determined, for example, by admission to hospital, or prolongation of 
hospitalization, where this is to be expected in the underlying disease or condition. 
All adverse events (AE) life-threatening or resulting in death will be notified within 24 
hours. All AE that are not life-threatening will be notified within 15 days. The rest of AE 
will be recorded and analyzed at the end of the study. 
 
 
9. Statistics 
9.1. Description of statistical methods. 

 
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The primary statistical aim is to compare the primary combined outcome “long-term 
survival without neuro-developmental disability at 3 years follow up” with a two-sided 
Cochran-Mantel-Haenszel-Test and a significance level of alpha=0.05. The primary 
outcome refers to a combined event in any of the twin and will be analysed for all 
pregnancies with available primary endpoint. The stratified study design is accounted 
by this stratified test according to the gestation groups.   
The main statistical evaluation will be performed at two time points. (1) The complete 
data set for the secondary endpoints will be available after the last women enrolled in 
this study has delivered her twins, so the analysis of these outcome parameter will be 
done right after this event. (2) The primary outcome will be evaluated 3 years after 
the last woman enrolled in this study has delivered her twins.  
A descriptive analysis by preterm birth will be carried out calculating means and 
medians for quantitative variables and proportions with 95% confidence intervals for 
categorical variables. In general, statistical comparisons with the pessary arm and 
the control arms or other group comparisons for primary and secondary outcomes 
will be performed with stratified tests as well as comparisons in the gestation 
subgroups. Events will be analysed for each twin and for single children assuming 
appropriate random effect regression models. Further subgroup analyses regarding 
the cervical length will be performed (e.g. CL 15 to 25mm and below 15mm). All 
tests, see also examples in the synopsis, will be two-sided using a significance level 
of alpha=0.05.  
For the primary endpoint we expect to have a drop out rate of up to 25% due to the 
long follow-up time (3 years) of the study; but we do not expect to have lost data for 
the secondary endpoints because for these parameters the study has a short follow-
up time till time to birth only. 
An interim analysis shall be conducted on key safety parameters after birth of 300 
twins: the following safety endpoints will be assessed by a one-sided test with 
alpha=1%  
• 
on level of the neonates: rate of preterm birth, time to birth, birth weight, death, 
neonatal morbidity, harm of intervention  
• 
and on the maternal level: rate of hospitalisation for threatened preterm labour < 
32 weeks, rate of PRoM <32 weeks, rate of infection / inflammation, rate of 
physical or psychological intolerance to pessary, rate of SAR/SAE, death. 
The trial will be terminated as negative if a disadvantage for the pessary-treatment 
can be found in one of these tests. To guarantee a high safety level the significance 
level is chosen more conservatively than in a Bonferroni correction. 
All analysis will be carried out with SPSS® version 19.0 or later (IBM Company 
SPSS Inc. Headquarters, Chicago, Illinois. USA) and R version 3.2.3 or later (R 
Foundation for Statistical Computing, Vienna, Austria). 
 
 
Primary Outcome 
Statistical Test 
Children`s Long-Term Survival without 
Neuro-developmental Disability  
(3-Years-follow up) 
Cochran-Mantel-Haenszel-Test, using 3 strata 
according to WoG 
Secondary Outcome 
Statistical Test 
Birth before 34 Weeks of Gestation 
Cochran-Mantel-Haenszel-Test, Chi-Quadrat Test 
Time to Birth 
Cox-Regression  
Birthweight 
van Elteren Test, Wilcoxon-Mann-Whitney Test 
Fetal / Neonatal Death 
Cochran-Mantel-Haenszel-Test, Chi-Quadrat Test 
Neonatal Morbidity 
Cochran-Mantel-Haenszel-Test, Chi-Quadrat Test 
Need for Hospitalization (mother) 
Cochran-Mantel-Haenszel-Test, Chi-Quadrat Test 
Days of Hospitalzation (mother) 
van Elteren Test, Wilcoxon-Mann-Whitney Test 
Maternal Adverse Events 
Cochran-Mantel-Haenszel-Test, Chi-Quadrat Test 
Pessary Intolerance 
Cochran-Mantel-Haenszel-Test, Chi-Quadrat Test 
Vaginal Infections 
Cochran-Mantel-Haenszel-Test, Chi-Quadrat Test 

 
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9.2. Expected number of subjects to be included. 
 
For sample size calculation, we account for the stratified design and assume three 
equally large gestation groups. For the pessary group, we assume a combined event 
rate of at least 8% for the primary outcome and for the comparison of the pessary 
group with the control group we assume an odds ratio of 2.29. This odds ratio 
correspond to the lower bound of a one-sided confidence interval for the event rate 
given in van´t Hooft (ProTwin Trial12). To reach a power of at least 80%, we have to 
evaluate at least 500 patients, 250 in the pessary group and 250 in the control group. 
To account for a drop out rate of 25%, overall n=672 pregnant women will be 
recruited. 
 
9.3. Criteria for termination of the trial.  
 
A non-justified case of maternal death (temporary stop until complete evaluation of 
the case by an external committee). 
 
9.4. Selection of subjects to be included in each analysis.  
 
The analysis will include all the subjects that have been randomised. 
 
 
10. Direct Access to Data Source 
 
Direct access will be granted to the authorized monitor, host institution and the 
regulatory authorities to permit trial-related monitoring, audits and inspections. 
 
 
11. Quality and Control Assurance 
 
Main investigator and collaborators: In order to ensure the Quality of the data they will 
provide instructions and training to the sites involved in the trial; review the CRF data; 
and detail of any other steps taken to ensure quality of research. 
The main investigator will sign the study protocol and the “investigator’s commitment; 
he will apply for the Ethics Committee and the Director’s approval; and he will review 
the final report of the study. 
The collaborators will assess patient’s eligibility, they will inform the patients and ask 
for the informed consent; and they will be responsible of the CRF and obtaining and 
registering all data. 
 
Monitor: he will perform regular monitoring according to ICH GCP. Data will be 
evaluated for compliance with the protocol and accuracy in relation to source 
documents. Monitors will verify that the clinical trial is conducted and data are 
generated, documented and reported in compliance with the protocol, GCP and the 
applicable and local regulatory requirements.  
 
Serious Breaches: A serious breach is defined as “A breach of GCP or the trial 
protocol which is likely to effect to a significant degree: (a) the safety or physical or 
mental integrity of the subjects of the trial; or (b) the scientific value of the trial”. All 
serious breaches will be notified to the competent Regulatory Authority according to 
applicable legislation. 
 
 

 
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12. Ethical issues 
 
The Sponsor, participating Centres and Investigator will ensure that this study is 
conducted in accordance with the Protocol, the principles of the Declaration of 
Helsinki (see annex III), ICH Guidelines for Good Clinical Practice and in full 
conformity with relevant regulations as well as applicable national laws, the German 
Law and in accordance with regulations and guidelines applicable to clinical trials 
relating to medical devices. 
The protocol, informed consent form, participant information sheet and any 
applicable documents will be submitted to an appropriate Ethics Committee (EC) and 
Regulatory Authority for written approval. All substantial amendments to the original 
approved documents will be also sent to an appropriate Ethics Committee (EC) and 
Regulatory Authority for written approval. The study will not begin until the approval 
of the EC and Director’s consent. 
 
 
13. Data Management and Registry File 
 
Patient’s participation in the study will be annotated into the medical history. 
The main investigator will perform a list with the participant’s names, ID numbers and 
codes. He also will have a file with all the information referring to the study. 
All the data will be collected in a database that will be accessed worldwide.  
The randomisation will be done on a computer basis. Once entering in the website, if 
the patient fulfils the inclusion criteria, the computer generated list will randomise the 
patient to “pessary” or “control” group. 
The excluded patients will be also collected in the database. 
Every participating centre will have its own randomisation list, and it will be 
accessible with a username and password. 
The trial staff will ensure that the participants’ anonymity is maintained. Only a 
participant ID number on the CRF and in the electronic database will identify the 
participants. All documents will be stored securely and only accessible by trial staff 
and authorized personnel. The study will comply with the Data Protection Legislation 
that requires data to be anonymized as soon as it is mandatory to do so. 
 
13.1. Data ownership 
Sponsor and participating Center have expressly agreed that any and all data collected 
and prepared in the context of the study shall be the property of the Sponsor, provided 
that participating Center shall remain the owner of its source data and may utilize such 
data as it deems appropriate without the approval, but with the reliable communication 
of Sponsor. Furthermore, Sponsor will always have access to the Study data, in terms 
of good faith and cooperation, in order to improve their own knowledge and 
information. 
 
 
14. Funds and Insurance 
 
According to German legislation and Ethical Committee decisions, it is not necessary 
to enter into an insurance contract in order to cover patients while using this medical 
device in a clinical trial. Insofar as it has been issued with the appropriate certificate 
of the State Medicines Agency to the concrete use of the medical device. 
  
Nevertheless, it will be mandatory to enter into a hedging insurance by any other 
participating centre of this clinical trial, in the case that it is mandatory according to the 
laws of their country. 
 

 
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No funding is provided for the study. 
 
 
15. Publication policy 
 
The Sponsor takes the commitment of publishing the results of the study; despite they 
are good or bad. 
 
Promoter and participating Centre agree that publications or presentations of any of 
the results from the study shall be in accordance with accepted scientific practice, 
academic standards and customs.   
 
Authorship and other related publications questions shall be addressed in accordance 
with the principles of the ‘Uniform Requirements for Manuscripts Submitted to 
Biomedical Journals’ and in accordance with the requirements of the respective 
medical journal. 
 
Sponsor agrees to ensure co-authorship for clinical co-investigators on any proposed 
multicentre publication.  
 
Sponsor and participating Centres agree that at first they will strive to make a joint 
publication. After such joint publication or one year after termination of the study the 
following shall be agreed: 
 
As a general principle, the parties agree that prior to submission of a publication or any 
other dissemination of the results, including oral presentation, the Sponsor shall have 
the right to prior review and comment on the content of the material to be published or 
presented within sixty (60) days following the receipt of the publication or any other 
dissemination of the results, and Participating Centre ensures that it will take 
Promoter’s comments into due consideration.  
 
 
16. Legal Issues 
 
Both the Promoter and the participating Centre will enter into a contract (Annex V) 
before they can start randomizing patients. 
This contract will prevail in case of lack of agreement from any of the parts. 
 
 
17. References 
 
1. Hille ET, Weisglas-Kuperus N, van Goudoever JB, et al. Functional outcomes 
and participation in young adulthood for very preterm and very low birth weight 
infants: the Dutch Project on Preterm and Small for Gestational Age Infants at 19 
years of age. Pediatrics 2007; 120: e587–95.  
 
2. Mwaniki MK, Atieno M, Lawn JE, Newton CR. Long-term neurodevelopmental 
outcomes after intrauterine and neonatal insults: a systematic review. Lancet 
2012; 379: 445–52. 
 
3. Schaaf JM, Mol BW, Abu-Hanna A, Ravelli AC. Trends in preterm birth: singleton 
and multiple pregnancies in the Netherlands, 2000–2007. BJOG 2011; 118: 
1196–204. 
 

 
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4. Martin JA, Hamilton BE, Osterman MJK, Curtin SC, Mathews TJ. National vital 
statistics reports. Births: final data for 2013. 2015. 
 
5. To MS, Skentou CA, Royston P, Yu CK, Nicolaides KH. Prediction of patient-
specific risk of early preterm delivery using maternal history and sonographic 
measurement of cervical length: a population-based prospective study. 
Ultrasound Obstet Gynecol 2006;27:362-7. 
 
6. Conde-Agudelo A, Romero R, Hassan SS, Yeo L. Transvaginal sonographic 
cervical length for the prediction of spontaneous preterm birth in twin 
pregnancies: a systematic review and meta-analysis. Am J Obstet Gynecol 
2010;203:128.e1-12. 
 
7. Arabin B, Alfirevic Z. Cervical pessaries for prevention of spontaneous preterm 
birth: past, present and future. Ultrasound Obstet Gynecol 2013;42:390-9. 
 
8. Liem S, Schuit E, Hegeman M, Bais J, de Boer K, Bloemenkamp K, et al. 
Cervical pessaries for prevention of preterm birth in women with a multiple 
pregnancy (ProTWIN): a multicentre, open-label randomised controlled trial. 
Lancet. 2013;382(9901):1341-9. 
 
9. Liem SM, Schuit E, van Pampus MG, van Melick M, Monfrance M, Langenveld J, 
et al. Cervical pessaries to prevent preterm birth in women with a multiple 
pregnancy: a per-protocol analysis of a randomized clinical trial. Acta Obstet 
Gynecol Scand. 2016;95(4):444-51. 
 
10. Goya M, de la Calle M, Pratcorona L, Merced C, Rodo C, Munoz B, et al. 
Cervical pessary to prevent preterm birth in women with twin gestation and 
sonographic short cervix: a multicenter randomized controlled trial (PECEP-
Twins). American Journal of Obstetrics and Gynecology. 2016;214(2):145-52. 
 
11. Fox NS, Gupta S, Lam-Rachlin J, Rebarber A, Klauser CK, Saltzman DH. 
Cervical Pessary and Vaginal Progesterone in Twin Pregnancies With a Short 
Cervix. Obstetrics and Gynecology. 2016;127(4):625-30. 
 
12. Van ’t Hooft J. Long-term effects of cervical pessary for preterm birth prevention 
in twin pregnancy with short cervix: a 3 years follow-up of the ProTwin trial.  
AJOG2016. 
 
13. Nicolaides KH, Syngelaki A, Poon LC, de Paco Matallana C, Plasencia W, 
Molina FS, et al. Cervical pessary placement for prevention of preterm birth in 
unselected twin pregnancies: a randomized controlled trial. Am J Obstet 
Gynecol. 2016;214(1):3 e1-9. 
 
14. Monfrance JM, Schuit E, Groenwold RH, Oudijk MA, de Graaf IM, Bax CJ, 
Bekedam DJ, Mol BW, Langenveld J. Pessary placement in the prevention of 
preterm birth in multiple pregnancies: a propensity score analysis. Eur. J Obstet 
Gynecol. 2016; 197:72-77.  
 
15. Abdel-Aleem H, Shaaban OM, Abdel-Aleem MA. Cervical pessary for preventing 
preterm 
birth. 
The 
Cochrane 
database 
of 
systematic 
reviews. 
2013(5):CD007873. 
 
1

 
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18. Annex 
 
Annex I. Technical details of the device.  
 
The Arabin cervical pessary 
CE-certified for preventing spontaneous preterm birth (CE 0482 / EN ISO 13485: 2012 
+ AC:2012 annex III of the council directive 93/42 EEC). 
 
This pessary is used to treat pregnant women with cervical incompetence in order to 
support the cervix and sacralise it towards the sacrum.  
It may be indicated in pregnancies with a history of premature labour, multiple 
pregnancies or mothers who are exposed to physical strain (e.g. standing for a long 
time). It may also be indicated in pregnant women suffering from prolapse of the 
genital organs. 
The cerclage pessary can easily be folded and inserted without pain.  
 
In general, cerclage pessaries should have a height of 21-25 mm in singleton 
pregnancies and a height of 25-30 mm in multiple pregnancies or pregnant patients 
with complaints of prolapse. The width of the upper and lower diameter should be 
chosen depending on the individual constitution of the pregnant patient. 
Cerclage pessaries can be ordered in a non-perforated or perforated version. The 
perforations facilitate discharge to pass. 
 
Sizes and Models: Cerclage pessaries are classified according to 
• 
The lower larger diameter (65 or 70 mm)  
• 
The height (17, 21, 25, 30 mm) 
• 
The upper smaller diameter (32 or 35 mm) 
 
Dr. Arabin online shop. http://www.dr-arabin.de/e/cerclage.html