The three stages of labour are, thankfully, over. However, as you examine the placenta on a flat surface, you find yourself questioning if its entirety has been expelled. In this article, we discuss the placenta and why you should alert your veterinarian at the first signs of trouble.
A complete placenta almost embodies the shape of a foal in utero, with a lengthy body, two long horns and the umbilical cord.
The parts of the placenta include:
- The cervical star
- The pregnant horn
- The non-pregnant horn
- The umbilical cord
- The body of the uterus
It is understood that parturition and the rupture of the umbilical cord initiate the passing of the placenta and allow the uterus to shrink in size.
Upon expulsion, the placenta should appear intact, with no signs of trauma. However, even minor tears that aren’t obvious to the untrained eye, may indicate a serious problem.
If in doubt when examining your mare’s placenta, call your veterinarian straightaway. They will be able to assess if the placenta has been fully passed. Any mare that hasn’t expelled the placenta within three hours of birth requires immediate veterinary treatment.
A Retained Placenta
During a normal birthing, strong uterine contractions will continue after the foal has been delivered to enable your mare to pass the foetal membranes, or placenta. At times, a complete or partial retained placenta may occur, with potentially devastating consequences.
Usually, retained foetal membranes follow a difficult birth, or dystocia. The uterus fatigues and your mare is simply unable to expel the placenta on her own. However, abortions, still births and foal deaths following birth are often implicated in retained foetal membranes.
If not treated within 12 hours of parturition, the reproductive health of your mare — and her very life — are at risk. Inside the uterus, retained foetal membranes can quickly lead to infection, toxic metritis and laminitis. At 24 hours, a retained placenta can be deadly.
Treating a Retained Placenta
Only a veterinarian should treat a complete or partial retained placenta. Forced removal of any part of the placenta by hand can lead to haemorrhage and even death, so it is never advised to attempt to manually remove the foetal membranes on your own.
If you notice any foetal membranes protruding from your mare’s vulva, knot them carefully to ensure they aren’t stepped on by mare or foal, and call your veterinarian. They will assess the degree of retention and put into action a treatment plan for its careful removal.