Vaginal and Cervical Tears in Horses: Birth Trauma in Mares

Vaginal and cervical tears, also called lacerations, are injuries to the mare's birth canal that can happen during or shortly after foaling. The vagina and cervix are soft tissues that stretch during delivery, but they can tear if the foal is malpositioned, the delivery is prolonged, or strong traction is used. Some tears are small and stay limited to the surface. Others are deeper and can involve surrounding tissues, blood vessels, or even the abdominal cavity.

These injuries matter because they are not only painful. They can also lead to blood loss, contamination of the reproductive tract, infection, poor healing, and later fertility problems. In some mares, the first signs are obvious right away, such as bleeding or distress. In others, the problem is found later during a postpartum reproductive exam, especially if the mare had dystocia or seems abnormal after foaling.

A mare can recover well when the injury is recognized early and matched to the right level of care. That may mean conservative monitoring for a minor tear, standard medical treatment and delayed repair, or advanced referral care for severe trauma. Your vet can help decide which path fits the depth of the tear, the mare's stability, and your breeding goals.

The most common cause is birth trauma during dystocia, which means a difficult foaling. In mares, dystocia is often related to abnormal presentation, position, or posture of the foal rather than a pelvis that is too small. When the foal is not lined up correctly, the mare may strain against tissue that is not ready to stretch, and the cervix or vagina can tear.

Risk goes up when delivery is prolonged, the foal is large or malformed, the cervix does not relax well, or strong manual traction is used before the foal is properly repositioned. Obstetric chains, forceful extraction, and repeated manipulation in the standing mare can all increase trauma if the case is not controlled quickly. Merck specifically advises that if vaginal delivery attempts are failing, rapid referral or cesarean section should be considered to spare the mare's caudal genital tract from further trauma.

Less often, vaginal tears can happen from breeding trauma, especially if there is a large size mismatch or accidental injury, but in broodmares the classic history is a hard foaling. Mares that have had previous reproductive trauma may also be more prone to scarring, poor tissue elasticity, or later fertility issues.

Diagnosis starts with history and urgency. Your vet will want to know when the mare foaled, whether the foaling was assisted, how long second-stage labor lasted, whether traction was used, and what signs have appeared since delivery. A physical exam checks heart rate, temperature, gum color, hydration, pain level, and whether the mare may be losing blood or developing infection.

A reproductive exam is usually needed. This may include a careful manual vaginal exam, vaginoscopy with a speculum, rectal palpation, and transrectal ultrasound. Merck recommends palpation and ultrasonography in postpartum mares to evaluate uterine involution, plus a manual vaginal exam to determine whether the reproductive tract was traumatized during foaling. Thorough cervical assessment may be easier after foal heat ovulation when the mare is in diestrus, because the cervix has more tone and shape for evaluation.

Your vet may also recommend bloodwork to look for blood loss, inflammation, or sepsis risk. If discharge, uterine fluid, or fertility concerns are present later, culture, cytology, or biopsy may be discussed, though Merck notes that postpartum mares normally have transient endometritis and some sampling is more useful after at least 3 weeks postpartum. In severe cases, referral imaging, endoscopy, or exploratory surgery may be needed to determine whether the tear extends into deeper tissues or the abdomen.

Not every birth injury can be prevented, but fast recognition of dystocia is one of the best ways to lower risk. Merck advises that a vaginal examination should be performed if the foal is not delivered within 30 minutes after rupture of the chorioallantois or if second-stage labor does not begin after more than 4 hours of obvious first-stage labor. In practical terms, a mare that is not progressing normally during foaling needs veterinary help quickly.

Good foaling supervision matters. Clean technique, early assessment of fetal position, and avoiding prolonged forceful traction can reduce trauma. If the foal cannot be repositioned safely in the standing mare, controlled vaginal delivery under anesthesia or cesarean section may protect the mare's reproductive tract better than repeated difficult extraction attempts.

After any hard foaling, ask your vet for a postpartum reproductive exam even if the mare seems fairly comfortable. Merck recommends manual vaginal examination in postpartum mares to check for trauma, and mares with dystocia or retained placenta need more extensive evaluation. That early check can catch tears before they become infections, chronic scarring, or future breeding problems.