Premature Placental Separation (Red Bag Delivery) in Horses

Premature placental separation is an uncommon occurrence but a frequent cause of abortion, stillbirth, and perinatal death in foals. It is an emergency situation that requires immediate action. Veterinary attention is required, but unless the veterinarian happens to be on site, the foal cannot wait for their arrival. The birth attendant must work quickly to release the foal from the placenta before the lack of oxygen causes brain damage or death.

This condition is not more dangerous to the mare when compared to normal birth. Mares who have experienced premature placental separation are not in more danger of it recurring in subsequent births, nor are they typically impaired from future pregnancies.

Risk factors that increase the risk of premature placental separation include:

• Placentitis
• Fescue toxicity (poisoning by grazing of the fescue plant)
• Stress

The severity of premature placental separation depends on how quickly the foal is released from the chorioallantois.

Foals that are released quickly are likely to have mild hypoxia (lack of oxygen being delivered to the brain and other tissues). Symptoms include:

• Hyperexcitability
• Weakness
• Lack of interest in the mare
• Lack of suckling reflex
• Unwillingness to stand
• Blindness
• Walking into objects, including the mare

Some of the symptoms of mild hypoxia take time to develop.

Foals that are not released quickly die from lack of oxygen.

The causes of premature placental separation are not fully understood. In some cases, mares have experienced placental infections, fescue toxicity, or excessive stress during the pregnancy. In many cases, however, the cause remains unknown.

During gestation, the fetus develops within the uterus of the mare inside a placenta composed of two membranes. The outer membrane is called the chorioallantois. The inner membrane surrounding the foal is called the amnion. The chorioallantois delivers oxygen and nutrients to the fetus.

In normal birth, the chorioallantois ruptures near the cervix, releasing the allantoic fluid (i.e. the water breaks) and allowing the amnion to descend into the birth canal. The foal, still inside the grayish-white membrane of the amnion, is born. During this time, the chorioallantois remains attached to the uterine wall, delivering oxygen and nutrients to the foal until the umbilical cord is broken.

In the case of premature placental separation, the chorioallantois fails to rupture. Instead, it separates from the uterine wall and begins to descend through the birth canal. Once it is separated from the uterus, the flow of oxygen and nutrients stops. The foal is no longer receiving the oxygen its brain needs to continue functioning, and cannot breathe oxygen due to the membrane over the foal’s head.

The only symptom of premature placental separation is the appearance of the red, velvety chorioallantois at the vaginal opening during birth, instead of the smooth, grayish-white amnion.

Premature placental separation is an emergency situation that demands immediate first aid. Veterinary attention is required for the foal, but unless the veterinarian is on site, the foal cannot wait for them to arrive. The birth attendants must work quickly to cut open the chorioallantois as soon as possible to release the foal and allow access to oxygen.

It is recommended that every foaling station be equipped with an emergency kit that includes a sharp knife or scissors in case premature placental separation occurs.

Foals that have been born under these conditions require veterinary attention, even in cases where the foal seems to be healthy upon delivery, as some symptoms do not develop immediately. Evaluation of the foal’s overall health may include:

• Physical examination
• Evaluating blood oxygen levels
• Evaluating antibody levels
• Bloodwork

If the newborn foal is not breathing, CPR must be performed. CPR is performed by:

• Picking the foal’s head up by the muzzle while the body is lying on its side
• Stretching the neck to a 30 to 45 degree angle
• Holding the mouth and lower part of the nostrils closed
• Creating a firm seal between the lips of the person performing the CPR and the open portion of the foal’s nostrils
• Blowing forcefully into the nostrils
• Watching to see the rise and fall of the chest
• In cases where the stomach rises and falls instead of the chest, readjusting the angle of the neck until the air is being delivered into the chest is necessary

In severe cases, hospitalization of the foal is required. Oxygen therapy and other supportive therapies are necessary.

The prognosis is guarded for foals born when there is a premature placental separation. In some cases, where the birth attendant is experienced and acts quickly, the foal is not left without oxygen for too long, and the prognosis is fair. In cases where the foal remains in the chorioallantois and without air, significant damage to the brain occurs. In some cases, the foal does not survive. Foals who survive often require intensive care in hospital to help prevent bacterial infections or malnutrition from developing.

The prognosis for a mare who has experienced premature placental separation is good. She is in no greater danger than with a normal birth. Future pregnancies are possible, and no greater risk of recurrence of premature placental separation is expected.

There are no proven preventative measures for premature placental separation.

To prevent significant brain damage or death to the foal, it is recommended that an emergency kit be kept at each foaling station including a knife or scissors to be used in case of premature placental separation.

Premature placental separation is uncommon to rare in pregnancies overall, but is a frequent cause of abortion, stillbirth, and perinatal death.

• Cutting the foal out of the chorioallantois