Placental Characteristics Within Monochorionic Twin Pregnancies

NCT07124312 | Recruiting

• 1 other identifier: 24/BW/MAT/NO/852
• Study Type: observational
• Target: 65
• Locations: 1 country
• Sites: 1

Brief Summary

This prospective study aims to collate a comprehensive database of all main monochorionic twin groups to enable comparisons to be made within each twin group and additionally between each group with regards to several placental characteristics, whilst understanding their impact on several fetal outcomes. This study aims to provide new insights in to how the placental architecture influences pregnancy care within the UK pregnancy cohort. Results of this study may impact how clinicians conduct antenatal surveillance for these anatomical placental factors. Patients of both uncomplicated and complication monochorionic twin groups will be consented at a single site and recruited during the antenatal period. Following delivery the placenta will then be analysed macroscopically and assessed for several anatomical features. This will be compared with the antenatal complications and perinatal outcomes for the respective twin.

Conditions

Placenta; Monochorionic Twins; Anatomy

Outcome Measures

Primary Outcomes (3)

• What is the impact of intertwin vascular anastomoses on fetal complications and perinatal outcome

  To determine the prevalence of intertwin vascular anastomoses (overall, artery-artery, artery-vein, vein-vein) on adverse perinatal outcome (e.g. stillbirth and neonatal death) and fetal complications (e.g. small for gestational age). Measures will be as overall percentages and also raw numbers which will be calculated in to odds ratio's when comparing anastomoses versus no anastomoses against the respective perinatal outcome and fetal complication

  Throughout the study period (approximately 2 years)

• What is the impact of abnormal cord insertion on fetal complications and perinatal perinatal outcome

  To determine the prevalence of abnormal cord insertion (marginal and velamentous) on adverse perinatal outcome (e.g. stillbirth and neonatal death) and fetal complications (e.g. small for gestational age, selective growth restriction). Measures will be as overall percentages and also raw numbers which will be calculated in to odds ratio's when comparing abnormal cord insertion versus normal cord insertion against the respective perinatal outcome and fetal complication

  Throughout the study period (approximately 2 years

• What is the impact of twin placental sharing on fetal complications and perinatal outcome

  To determine the impact of placental sharing between each twin on adverse perinatal outcome (e.g. stillbirth and neonatal death) and fetal complications (e.g. birthweight discordance and selective growth restriction). Placental sharing will be defined as a percentage of overall share between each twin which sums up to 100%. The difference between each twin's share will be determine by minimising the larger percentage from the smaller percentage. The difference will then be compared to adverse perinatal outcomes and complications such as selective growth restriction using odds ratio's. Birthweight discordance will be defined as a percentage ( difference between the larger twin weight and smaller twin weight, divided by the larger twin weight). This will be compared to placental sharing using a graphical comparison of all placental sharing results, individually compared against each respective birthweight discordance.

  Throughout the study period (approximately 2 years)

Secondary Outcomes (8)

• The influence of abnormal cord insertion in monochorionic twins complicated by twin-twin transfusion syndrome

  Throughout the study period (approximately 2 years)

• The influence of residual vascular anastomoses monochorionic twins complicated by twin-twin transfusion syndrome

  Throughout the study period (approximately 2 years)

• The influence of abnormal cord insertion on residual anastomoses development in monochorionic twins complicated by twin-twin transfusion syndrome undergoing laser ablation

  Throughout the study period (approximately 2 years)

• Examine the association between Quintero staging during laser ablation for monochorionic twins complicated by twin-twin transfusion syndrome on residual anastomoses development

  Throughout the study period (approximately 2 years)

• Examine the relationship between placenta position during laser ablation for monochorionic twins complicated by twin-twin transfusion syndrome and the rate of residual anastomoses development.

  Throughout the study period (approximately 2 years)

Study Arms (2)

Uncomplicated monochorionic twins

Monochorionic twins which do not develop any complications during the antenatal period

Complicated monochorionic twins

Monochorionic twins which develop any type of complication during the antenatal period such as TTTS, sIUGR and TAPS.

Eligibility Criteria

• Sex: female
• Healthy Volunteers: Yes
• Age Groups: Child (0-17), Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Placentas received within the pathology department from monochorionic twin groups . These groups include: * Uncomplicated monochorionic twins * Monochorionic twins with complications (e.g. selective intrauterine growth restriction, twin-twin transfusion syndrome , twin anaemia-polycythaemia sequence etc).

You may qualify if:

• All consecutive placentas of monochorionic twin pregnancies whereby the placenta is transferred to the pathology department for analysis.

You may not qualify if:

• Singleton, dichorionic and higher order pregnancies (e.g. triplet).
• Fetus with known major congenital anomalies or aneuploidy

Sponsors & Collaborators

• Birmingham Women's NHS Foundation Trust: lead

Study Sites (1)

Birmingham Women's and Children's NHS Foundation Trust

Birmingham, West Midlands, B15 2TG, United Kingdom

RECRUITING

Study Officials

• Jack Hamer, MBChB

  Birmingham Women's and Children's NHS Foundation Trust

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Jack Hamer, MBChB

CONTACT

0121 472 1377; jack.hamer1@nhs.net

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER GOV
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Clinical research fellow

Study Record Dates

• First Submitted: August 1, 2025
• First Posted: August 15, 2025
• Study Start: December 12, 2024
• Primary Completion (Estimated): January 1, 2027
• Study Completion (Estimated): February 1, 2027
• Last Updated: August 15, 2025

Record last verified: 2025-08

Data Sharing

• IPD Sharing: Will not share

Locations

GB (1)