10/04/2025
What is a Breeding Soundness Exam (BSE)? This is an evaluation of the fertility potential of a mare. A typical exam involves evaluating the external conformation of the mare including her vulvar shape, size, seal, and position as well as the perineal conformation, presence of a caslick’s, and any obvious abnormalities. Next an ultrasound exam of the cervix, uterus, and ovaries is performed to note the health and status of the reproductive tract as well as identify things that may cause potential problems for breeding such as uterine cysts, ovarian tumors, or cervical changes. Finally, a speculum exam is performed to visualize the vaginal vault and cervix to look for things like urine pooling, mucous accumulation, persistent h***n, varicose veins, and cervical tears, adhesions, or strictures. Standard practice is to obtain a sample from the uterus for culture and cytology, and occasionally a uterine biopsy is performed if there is a history or suspicion of chronic endometritis. Hormone testing may be performed based on the initial exam.
Why get a BSE? Identifying potential issues prior to the breeding season allows us to better plan and treat your mares without wasting precious cycles in season. Many conditions found on a BSE are treatable/manageable and early intervention increases fertility odds.
When to get a BSE? It is important to perform a BSE PRIOR to the breeding season so that we have time to address any problems that may arise. Depending on your goals for the season and stallion availability, exams can be conducted December through February. It is especially important to evaluate potential donor and recipient mares for embryo transfer so proper planning for the season can be performed.
Pictured below is an ultrasound of a mare with many uterine cysts. It is important to be aware of the presence of cysts as they can influence the success of insemination and embryo implantation as well as make early pregnancy detection more challenging.