Fetal membrane closure techniques after hysteroamniotomy in the midgestational rabbit model

OBJECTIVE: We studied closure techniques for amniotic access in midgestational rabbits. STUDY DESIGN: Twenty-eight rabbits with a total of 313 amniotic sacs were used for this study. In each animal a 1 cm hysteroamniotomy was made in two amniotic sacs at 22 daysʹ gestation (term = 32). For 12 amniotic sacs (group 1) only the myometrium was closed by microsurgical suturing. In group 2 (n = l2), sutures included myometrium and membranes. In group 3 (n = 8), a collagen plug was placed, and in group 4 (n = 12) fibrin glue was used. Twelve sacs were left unclosed (positive controls) and the unmanipulated 257 sacs were negative controls. Eight days later (gestational age 30 days) amniotic sacs were evaluated for the presence of amniotic fluid, membrane integrity, and fetal weight and survival. Statistics were done with two-tailed Fisherʹs exact test and one-way analysis of variance. RESULTS: Membrane integrity (p = 0.0036) and amniotic fluid (p = 0.047) were best restored after myometrial closure. Fetal weight and survival rate were not affected by different closure techniques. CONCLUSION: In this model primary closure of the myometrium only yielded best results. (Am J Obstet Gynecol 1998;178:938-42.)