Investigating the peri and post-operative outcomes of neutering female dogs by ovariohysterectomy or ovariectomy

12 October 2025

Professor Gary England from the University of Nottingham received BSAVA PetSavers’ funding for a student research project comparing two different methods of neutering surgery for bitches. Student Elaine Yarwood carried out the study in her third year and describes her findings here.

Introduction

Neutering is a common procedure undertaken to prevent bitches from producing offspring by removing the hormonal source controlling reproduction (Figure 1). Neutering by ovariohysterectomy (OVH) is reportedly the most common procedure; however, neutering by ovariectomy (OVE) is increasing in frequency. The main neutering surgery taught in veterinary schools and performed in practice is still OVH by celiotomy, although laparoscopic techniques and OVE surgeries are becoming increasingly common. It has been shown that surgeon experience can influence the outcomes from neutering surgery using both methods, and, for laparoscopic OVE, familiarity and experience with techniques and equipment have a positive influence on surgery time and outcome. The results of this study aim to support the requirement to teach this important surgical technique to veterinary students and to promote its use in practice to benefit bitch wellbeing.

Bitch ready for surgical neutering.

Study hypothesis and aims

The study hypothesis was that neutering surgery performed by laparoscopic OVE would have a shorter duration, with fewer peri- and post-operative complications reported, than for neutering performed by OVH by celiotomy. It was designed as a retrospective study to compare complication rates of neutering at three different timepoints: during surgery, in the immediate postoperative period, and during the days following surgery. The data covers surgical neutering using two different techniques: laparoscopic ovariectomy (LAP-OVE), which offers a more minimally invasive approach, and ovariohysterectomy by celiotomy (OVH-CEL), a currently more commonly used technique requiring a larger incision. Objectives were to identify any significant differences in surgery duration or perioperative complications reported by veterinary surgeons for bitches that were neutered by LAP-OVE compared with OVH-CEL, as well as any significant differences in wound healing and unusual behaviours displayed in the days post-surgery.

Study findings

The results of the study showed no significant differences in surgery duration between LAP-OVE and OVH-CEL surgeries. Complications in the perioperative period, including postoperative complications prior to being discharged, were reported for less than 3% of bitches in both groups. In the days following surgery, fewer LAP-OVE bitches (16.3%) than OVH-CEL bitches (36.6% of all OVH-CEL, 43.1% of OVH-CEL surgeries carried out at one of four veterinary practices where data was collected from [VP3]) were reported with redness or swelling of the wound site. Additionally, fewer LAP-OVE bitches were reported to have complications in the postoperative period that required veterinary attention (12.9%) than OVH-CEL bitches (16.3% and 24.0% for all and VP3 OVH-CEL bitches, respectively). Finally, unusual behaviours were reported in fewer bitches in the days following laparoscopic ovariectomy than following ovariohysterectomy by celiotomy.

Discussion

The project succeeded in obtaining statistical results in comparing LAP-OVE with OVH-CEL with regards to surgery length and was able to present descriptive data on peri- and postoperative complications. OVH-CEL surgeries were performed by only one of the four practices included in the study. This was factored into comparative analysis, noted as different descriptive data for all OVH-CEL surgeries and VP3 OVH-CEL surgeries.

For all postoperative outcomes, there were fewer LAP-OVE than OVH-CEL bitches reported to be affected. The findings provide evidence to support the contention that postoperative complications, including those related to wound healing and those requiring further veterinary intervention, are lower following laparoscopic surgeries than open neutering surgeries in bitches. This may suggest the benefits of LAP-OVE surgeries for bitches in small animal practice where laparoscopic instruments and training can be provided. Further research would be recommended to consolidate these findings.

As data collection methods for LAP-OVE bitches differed from OVH-CEL bitches, there were limitations to how much data could be used in direct comparison via data analysis in SPSS. This resulted in surgery length being the only standardised data used for analysis. Attempts were made to standardise the data for both surgery groups, collecting data only from clinical records for both; however, this resulted in insufficient data for OVH-CEL as veterinary surgeons gathered this data in the form of questionnaires given to them at the time of peri- and postoperative observance. This meant that clinical records had insufficient data for OVH-CEL bitches and therefore only surgery length was statistically analysed. Descriptive data was collected and presented for all categories observed in the peri- and post-operative period.

 Applying to BSAVA PetSavers for funding

My part in this project was kindly funded by BSAVA PetSavers, which made my first involvement in research possible. During my work on the project, I gained experience in scientific writing, research, data analysis, and overcoming unforeseen obstacles that occur due to the nature of research. Particular gratitude is addressed to BSAVA PetSavers for funding this research project as it has allowed me the opportunity to gain valuable insight and skills that would otherwise not have been possible as a 3^rd year vet student. The opportunity to conduct a research project supported by BSAVA PetSavers is highly recommended to any other students who hope to take the first step into research before finishing their studies.

 About the author

As part of her extracurricular clinical studies, Elaine Yarwood has recently completed this fascinating research project as a 3rd year Veterinary Medicine and Science student, studying at the University of Nottingham. As a team with her supervisors Rachel Moxon and Gary England, she has worked to complete a paper for publication on the peri- and postoperative outcomes of neutering in bitches spayed via laparoscopic ovariectomy and ovariohysterectomy via celiotomy.

Elaine Yarwood and Gary England

Having ambition for progression and advancing personal knowledge in subjects such as neurology and urogenital physiology in small animal veterinary medicine, she engaged with presentations and academic talks which led to an introduction to different current projects being offered to undergraduate students interested in research. After completing the project, she now wishes to pursue further work in the field of veterinary research, recognising the positive impact projects such as this one can have on the welfare of animals in small animal practice.

Supporting more BSAVA PetSavers research

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