A New Methodology to Measure Strength of Adherence of the Fetal Membrane Components, Amnion and the Choriodecidua

• Published in: Placenta (Eastbourne) Vol. 30; no. 6; pp. 560 - 563
• Main Authors: Kumar, D, Novince, R, Strohl, A, Mercer, B.M, Mansour, J.M, Moore, R.M, Moore, J.J
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01-06-2009; Elsevier
• Subjects: Adhesiveness; Amnion; Amnion - pathology; Amnion - physiology; Biological and medical sciences; Biomechanical Phenomena - physiology; Biomechanical testing equipment; Calibration; Chorion; Chorion - pathology; Chorion - physiology; Decidua - pathology; Decidua - physiology; Diagnostic Techniques, Obstetrical and Gynecological - instrumentation; Embryology: invertebrates and vertebrates. Teratology; Extraembryonic Membranes - pathology; Extraembryonic Membranes - physiology; Female; Fetal membrane adherence; Fetal membranes; Fetal Membranes, Premature Rupture - diagnosis; Fetal Membranes, Premature Rupture - pathology; Fetal Membranes, Premature Rupture - physiopathology; Fundamental and applied biological sciences. Psychology; Humans; Internal Medicine; Obstetrics and Gynecology; Pregnancy; Shear Strength - physiology; T-peel testing; Tensile Strength - physiology; Fetal membranes; Amnion; T-peel testing; Chorion; Fetal membrane adherence; Biomechanical testing equipment; Vertebrata; Mammalia; Methodology; Fetal membrane; Adhesion; Fetoplacental membrane; Strength
• ISSN: 0143-4004; 1532-3102
• DOI: 10.1016/j.placenta.2009.03.014

Abstract We have previously shown that separation of the amnion from choriodecidua occurs as an integral part of the fetal membranes (FM) rupture process. We have also reported that spontaneous separation of FM is nearly universal with term vaginal delivery. The etiology of this spontaneous FM separation is unknown. If biochemical degradation at the amnion–choriodecidua interface is a factor, decreased adhesive force between the FM components prior to their complete separation would be expected. The purpose of this project was to develop and validate machinery and procedures to measure the adhesive force between amnion and choriodecidua. Commercial tensile testing equipment was adapted to perform a standard T-peel test, per the American Society for Testing and Materials (ASTM) guidelines. FM test strip dimensions, peel speed, and peel force data measurements from force versus displacement curves were optimized for reproducibility. Test system validation was performed using Shurtape CP 60 (slow release painter's masking tape) as the standard. Equipment and procedures for a standard T-peel test on FM were developed. Shurtape CP 60 of decreasing widths showed reproducible, linear changes in the adhesive force range for FM ( r2 = 0.96). The adhesive force between FM components ranged from 0.017 to 0.262 N/cm. Reproducibility was optimal with FM test strips of 4 × 6 cm and a peel speed of 25.4 cm/min. FM showed greater adhesive force adjacent to the placental disc than distal from the disc ( p < 0.05). We have developed equipment and procedures to accurately and reproducibly measure adhesive force between the FM amnion and choriodecidua.