Fetoscopy in the pregnant rabbit at midgestation

Objective: To develop a small animal model for fetoscopy. Methods: In 12 ti me-dated pregnant rabbits at 22 days' gestational age (term 32 days) one am niotic sac in each uterine horn (n = 24) was used for a fetoscopic procedur e. After laparotomy, a 2- to 3-mm microsurgical myometrial incision was mad e to expose the chorionic and amniotic membrane. Under microscopic control, a 2-mm needle was inserted into the amniotic sac. Through this a 1.2-mm en doscope was passed to carry out fetoscopy during maximally 10 min, using 5- 10 ml saline amnioinfusion. Mean outcome measurements were ability to visua lize the placenta, umbilical cord and the different fetal elements during f etoscopy, as well as fetal survival and weight at second-look operation at 30 days. The untreated amniotic sacs served as negative controls. Results: In all cases, fetoscopy could be carried out successfully, and all fetuses survived till delivery without significant influence on fetal birth weight. Conclusion: The midgestational rabbit can be used to perform fetoscopy.