A Novel Intravaginal Contraceptive Plug for Cats: A Preliminary Biocompatibility Assessment on Haematology and Vaginal Swab

ABSTRACT This preliminary study evaluated the biocompatibility of a novel degradable intravaginal plug contraceptive composed of PEG 4000 and chitosan in cats using haematological profiling and vaginal cytology. Five healthy, non‐pregnant female cats were fully anaesthetised and fitted with an intravaginal plug (10 × 0.3 mm) using an applicator, following oestrogen administration 3 h prior. Blood samples were collected from the cephalic vein on days 0 (pre‐insertion) and 3 and 7 (post‐insertion). Vaginal cytology examinations were conducted on day 0 (pre‐ and post‐oestrogen injection) and days 1, 3 and 7 post‐insertion. Haematological parameters, including red blood cell count, haemoglobin levels, haematocrit values, total white blood cell count and differentiation, showed no significant changes after contraceptive insertion (p > 0.05). Vaginal cytology indicated an acute inflammatory response in one out of five subjects on day three post‐insertion. The distribution of vaginal epithelial cells (parabasal, intermediate and superficial) remained unaffected by contraception. Oestrogen injection resulted in the dominance of superficial cells up to day 7 of observation (p