A medical doctor once told me, "There’s only a 1% chance that a problem will develop, but if it develops in you, then it’s 100% a problem." So it goes with foaling: Foaling difficulties occur in less than 1% of births, but if it’s your mare, this statistic ceases to have any relevance.
When a dystocia (difficult birth) takes place, you usually have only a narrow time frame in which to obtain veterinary help. Understanding the normal birthing process, recognizing problems, and most importantly knowing what to do -- including what not to do -- could mean the difference between saving the mare and foal, or losing one or both.
"Mares always try to deliver in the dark and in solitude, usually between 10 p.m. and 6 a.m.," says Michele L. LeBlanc, DVM, Dipl. ACT, Director of the Equine Research Program at the University of Florida and recipient of the 2001 Theriogenologist of the Year Award (given by the American College of Theriogenologists for commendable work in research and service).
"They are animals of flight, so they prefer not to be seen; they never lost that through evolution," she continues. "Mares may also stop labor during first stage delivery if disturbed. They can delay parturition (birth) for a number of days as they wait for an undisturbed time."
Signs of imminent foaling are variable and can be subtle. For example, the udder might or might not develop wax on the teats six to 48 hours prior to foaling, and the mare might or might not leak milk several days prior to foaling. Each mare is an individual, although most mares will show similar signs year after year.
In all mares, the birthing process consists of three stages. However, not all mares will show the same signs of these three stages.
Stage One is not well-defined. LeBlanc says, "Some mares may show no signs of first-stage labor whatsoever, while others may act uncomfortable or restless, walk around with a raised tail, start to sweat in the flanks or behind the elbows, kick at their sides, urinate small amounts frequently, or alternately lie down and stand up."
During stage one labor, the foal rotates from a position of lying on his back with forelimbs and head tucked towards his tail to a position where his head and forelimbs are extended, one forelimb stretched out farther than the other toward the mare’s vulva.
This stage, if noticed, usually lasts 15-90 minutes.
Stage Two begins with the rupture of the placental membranes. "With that rupture, all of the allantoic fluids start to come out, and the foal should be presented at the lips of the vulva within three to five minutes," says LeBlanc. "Normally, one leg is seen first, with the other leg 10-15 centimeters behind the first leg, and then the head. The head and both front legs should be there within five minutes."
The mare usually lies on her side during this phase of labor. With each contraction, the foal advances through the vulva.
This stage is rapid, with normal delivery completed 15-45 minutes after the placental rupture.
Stage Three is the passage of the placenta. The placenta should be expelled within four to six hours. Some mares experience continued uterine contractions, exhibiting signs of abdominal discomfort such as lying down or rolling around. This should cease within one to two hours.
Clinical signs for various foaling problems differ according to what is wrong. Some signs are vague or absent during or immediately after foaling. Other problems are obvious, i.e., the foal not emerging, placental retention, placenta being delivered before the foal.
"Problems incurred at or immediately after foaling are considered emergencies," warns LeBlanc. "An ill postpartum mare requires a thorough medical examination followed by immediate, appropriate treatment if serious sequelae are to be avoided. Mishandled postpartum problems often lead to death of the mare and/or foal."
The postpartum examination must include physical, rectal, and manual vaginal examinations along with appropriate laboratory work to assess the status of the mare.
Following are some of the common situations, an explanation of what the problem involves, and what the horse owner should expect.
Premature separation of the placenta is where the placenta is delivered before the foal. Explains LeBlanc, "In this scenario, the mare lies down and begins to push. Those attending the mare will see a red bag at the lips of the vulva; this is the placenta. If this occurs, there is no time to call the veterinarian -- the placenta needs to be cut and the foal pulled out." Open the placenta with scissors (avoid cutting the foal), and help the foal to be delivered.
Immediate action is critical because the foal receives all of his oxygen supply through the connection between the placenta and the mother’s uterus until he is on the ground and breathing. "When the placenta comes first, the placenta is pulled away from the mother’s uterus and the in utero foal receives no oxygen," LeBlanc explains. "The foal can become hypoxic (suffering from a lack of oxygen) and can die."
Premature separation of the placenta isn’t common; when it occurs, it’s often in association with placental infection. "Sometimes we know beforehand through a prenatal exam (that there is a problem), but not in all cases," states LeBlanc. "While it was commonly thought that mares with placental infection would drip milk and have a vaginal discharge, research models where a low-grade infection was induced into the mare’s cervix revealed that not all infected mares had a discharge, but the majority did have premature placental separation."
Retention of the head can occur. Normally, one forelimb emerges from the vulva followed closely by the second foreleg, then the head. "Having one leg extended farther than the other leg facilitates the passage of the shoulders through the pelvis," LeBlanc says. But sometimes just one or both forelegs together emerge from the vulva, and the head and the rest of the foal fails to follow. This occurs because the foal did not flip itself into the stage two position needed for delivery, possibly because the mare was contracting and pushing so hard the foal was unable to position itself correctly. As a result of this malpositioning, as the forelegs emerge, the head and neck are bent backwards, creating an obstacle that prevents delivery.
"The head and both front legs should be there within five minutes of the ‘water breaking.’ If nothing is there, or just one of the legs appears, the owner should call for (veterinary) assistance," LeBlanc warns.
While waiting for the veterinarian’s arrival, get the mare up and walking to reduce the pressure of the foal in the birth canal and encourage the foal to fall back into the uterus.
"Sometimes if you get the mare up and walking, the problem corrects itself," LeBlanc says. "Walking is better than having a mare push and push, cause a constriction on the head of the foal, and possibly decrease blood supply to the head."
LeBlanc strongly encourages people who haven’t dealt with foalings before to resist attempting to pull the foal out. "If the head is retained or the head is only in the beginning of the pelvis and someone starts pulling on the leg, the head falls back into the mare’s abdomen and you can never get it back up successfully, in which case the foal dies. People get scared and start pulling on the leg and make the situation worse. That’s why it’s much better to get the mare up and walking and wait until you have (veterinary) assistance."
Vaginally delivering a foal with a retained head can be difficult or impossible, so a cesarean section is often necessary.
Dog-sitting dystocia is quite uncommon; a foal that is positioned in a dog-sitting posture is very unlikely to survive delivery.
In this situation, the foal is positioned similarly to the way a dog sits, with the toes of his hind legs coming forward instead of his hocks and hind legs being stretched out behind. Says LeBlanc, "The tips of the foal’s hooves may catch on the cranial (forward) brim of the pelvis or the hind limbs may move into the vagina alongside the body of the foal, impeding delivery. As a result, half of the foal is delivered and then, because of its dog-sitting position, the foal gets caught and stuck in the mare’s pelvis."
With the foal wedged into the mare’s pelvis, blood supply to the umbilical cord is shut off. There is no way to save the foal, and the mare is at great risk.
LeBlanc says there are no means to predetermine or prevent a dog-sitting foal. The veterinarian has to remove the dead foal by using a saw wire to cut the foal into three parts and pull the individual parts out while the mare is under local anesthesia. How the mare fares depends on how long the difficult birth goes on.
Hydrocephalus is an enlargement of the head caused by an accumulation of fluid within the skull. This occurs occasionally. Delivery is usually handled by incising the soft portion of the skull to release the fluids, thereby collapsing the skull. If the head is very enlarged, the enlarged portion is cut with a saw wire, collapsed, and delivered, allowing delivery of the rest of the foal.
Breech birth is when the two hind limbs are up underneath the foal and the rear end is presented first. The only way to correct this is to reverse the foal. That requires repelling the foal back into the uterus far enough so that he can be turned around.
Posterior presentation means that instead of the forelimbs and head posed to enter the birth canal, the foal’s hind end and legs are positioned toward the vulva. As the fetus starts to enter the birth canal, one of its hind limbs is retained at the mare’s pelvis, preventing passage of the foal.
If the foal is alive, he is repelled by a veterinarian, the retained hind leg corrected, and the foal delivered posteriorly (hind legs first).
If the foal is dead, one of the hind limbs can be amputated and a traction snare put on the other hock to ease the foal out.
Ruptured uterus can occur during delivery. Once torn, the uterus and the abdominal cavity are subject to contamination from the outside. Extreme contamination can occur because the cervix is wide open for delivery and the mare is lying on the ground. Therefore, she is exposed to more dirt, feces, and bacteria. Should contamination occur, the mare will develop peritonitis (inflammation in the lining of the abdomen).
"If the tear occurs during the birth process and the foal’s head and front limbs are there, the client might just pull the foal out" without realizing the internal damage, LeBlanc says. "It depends on when in second stage labor it happened as to the signs."
Clinical signs of a ruptured uterus can include extreme depression, inappetence, illness, and possible colic. The mare might not get sick for 12-24 hours after delivery.
"If she ruptures the uterus early during labor," continues LeBlanc, "the mare may stop labor or deliver the foal and become quite sick afterward." If the mare hasn’t foaled and shows these signs, she should be taken to a referral center or veterinary clinic where the foal can be delivered and the uterus repaired.
Prognosis depends on where and how large the tear is. If the tear is at the tip of the horn, the foal will be delivered normally, but the mare will get sick afterward. Another common area for tearing is in front of the cervix. A veterinarian can identify this condition by a vaginal examination of the uterus. The foal is delivered normally.
Rupture of the uterine artery can occur with deadly consequences. Blood vessels to the uterus can rupture and bleed into the uterus, uterine ligament (sheets of tissue that attach the uterus to the abdominal wall), or uterine wall. Additionally, the uterus or the ligament can rupture from the weight of the accumulated blood. Hemorrhage from a uterine artery is common in older mares and is a cause of death in a significant number of broodmares, LeBlanc reports.
Clinical signs of abdominal pain are nonspecific, sometimes making awareness of a problem difficult. Explains LeBlanc, "Colic signs may go unobserved if the delivery has gone normally, with the assumption that the mare is exhibiting pain from normal post-foaling uterine contractions. Many mares with post-partum hemorrhage are not recognized until they are weak or dead."
Diagnosis of bleeding into the ligament is via rectal palpation and ultrasonography of the uterus, ligament, and ovary.
Prognosis depends on where the blood leaks. Says LeBlanc, "If the uterus or ligament ruptures from the weight of the bleeding, the mare can bleed into the abdomen and she’ll die very quickly. If the ligament can hold, the mare may live."
If the ruptured artery bleeds in the uterine wall or uterus, a clot can form and halt the bleeding. Often, the mare will colic badly because of severe pain, but will probably live.
The long-term prognosis is good if the mare survives the crisis. Although scientific data doesn’t support that the episode will repeat in future deliveries, LeBlanc’s data indicates that ruptured uterine arteries are due to degeneration of blood vessels, which commonly relates to aging. "You can’t get rid of that degeneration," she notes.
Treatment is rest and quiet. "It’s most important to keep the mare quiet," LeBlanc states, "because the more the mare throws herself around and the more anxious she becomes, the higher the likelihood that a tissue may tear." The mare should be kept quiet until she stops colicking -- about six to 12 hours.
There are no surgical options. Explains LeBlanc, "During a hemorrhagic crisis, the blood dissects through all the tissues and you can’t find where the bleeder is."
Gastrointestinal (GI) problems are other possible complications. LeBlanc states that there are many GI complications that can occur with foaling:
- A ruptured gut due to gas;
- Foaling so violent that the vaginal wall ruptures, permitting the intestines to come out through the vagina;
- A ruptured large colon or cecum;
- A prolapsed rectum leading to torn intestinal structures, which allows the intestines to come out through the rectum;
- Torsion (twisting) of the large colon;
- A piece of gut that slowly dies after getting caught under the uterus during violent foaling.
Often, a mare suffering from one of these assorted GI disorders appears normal at the beginning of labor, but during second-stage labor her contractions are weak or absent. The foal might be delivered manually, but the mare does not recover normally. She might develop increased pulse and respiration rates, sweating, and shock.
"Prognosis of these problems depends on which one occurs and how severe," says LeBlanc. Death of the mare usually occurs within four to six hours after delivery. "If there’s a tear in the vagina, the prognosis is poor. If there is prolapse of the intestines through the rectum, prognosis is poor. If there is a hole in the cecum or large colon so that feces are freely floating in the abdomen, prognosis is poor. Prognosis is not so bad with a large colon torsion if there’s quick surgical intervention. Medical treatment for a piece of bruised colon can save the mare."
Retained placenta is the most common problem after foaling. If the placenta is retained, that tissue is dying, so now the mare has a piece of dying tissue in her uterus. The uterus communicates with the outside because the placenta is still attached and the cervix open. So external contaminants, plus the dead tissue of the placenta, provide a medium for bacterial growth inside the uterus, resulting in toxemia in the mare. If the mare doesn’t pass the placenta within four to six hours, it becomes a medical emergency because she can become very ill.
The veterinarian will administer drugs to the mare to cause the uterus to contract (thereby expelling the placenta), and also might administer antibiotics and anti-inflammatories.
"Eventually these medical therapies are effective," LeBlanc states. "We’d like to see the placenta come out within 24 hours, but that’s often not the case; if it doesn’t pass within 12 hours after starting therapy, it’s going to hang in there for quite a while -- it could be two to four days."
The retained placenta is never removed manually since it is easy to damage the uterus by this action. Also, hemorrhage and possibly death could ensue.
If the placenta is retained for a lengthy period, the mare can develop a very severe uterine infection. If the infection goes out into the body and becomes a systemic infection, the mare will become very sick. When the mare becomes systemically ill, she can develop laminitis.
"If she retains the placenta for more than 18 hours and she gets sick, the likelihood of her being bred that season decreases," says LeBlanc. "If the placenta passes within 18 hours, she should not be bred on foal heat, but could be bred 30 days later. This delay is necessary to allow time for the infection to clear and the inflammatory situation to resolve."
There is a bit of good news; just because a mare retains her placenta once does not necessarily mean she will retain the placenta in the future.
Words to the Wise
Acting improperly or waiting too long to summon the veterinarian can endanger the mare or foal. After normal rupture of the placenta, the fetal forelimbs should appear at the vulva within five to 10 minutes, with the foal being delivered within the next 10 minutes. A prolonged delivery is dangerous to the foal. Warns LeBlanc, "After 45 minutes, the majority of foals will die. You need to summon assistance quickly if delivery does not progress within five minutes of rupture of the placenta."
If you’re assisting the mare with her delivery, summon veterinary help if the mare doesn’t deliver completely within 10 to 15 minutes. "Assisting in a delivery is a very physical process and you become exhausted," says LeBlanc. "You may also damage the mare’s reproductive tract if you work that long. Then she’ll become damaged and extremely sick afterward because of it.
"These are situations where you have to make a decision quickly about what you’re going to do about a problem, and then act on that decision," LeBlanc emphasizes. "Here at the veterinary hospital, when we’re trying to deliver a foal, we give ourselves two or three minutes to succeed. If our game plan isn’t working, we switch game plans. But, while we’re trying to deliver the foal, we anesthetize the mare and clip (shave) her abdomen so if we can’t get the foal out within 30 minutes, we can send the mare into surgery for a cesarean section."
Because last-minute surgical intervention isn’t an option for farm deliveries, you need to recognize early signs of problems and act quickly and appropriately. Call your veterinarian if necessary or if you’re not sure you can handle the foaling. Your mare’s and foal’s lives may depend on it.
Call the veterinarian when:
- The foal doesn’t present the normal birthing appearance within five minutes after placental rupture.
- One or both legs appear, but the head doesn’t present within five minutes of placental rupture. (After summoning the veterinarian, try to get the mare up and walk her until the veterinarian arrives.)
- The placenta is retained for over 6 hours.
- After delivery, the mare exhibits abdominal pain, depression, or inappetence.
- If the foal is not up, standing, and nursing within two hours after birth.
Act first, then summon the veterinarian when:
- The placenta is delivered before the foal. Cut the placenta (be careful of the foal) and pull the foal out.
About the Author
Marcia King is an award-winning freelance writer based in Ohio who specializes in equine, canine, and feline veterinary topics. She's schooled in hunt seat, dressage, and Western pleasure.
POLL: Fly Masked-Marauders