Foaling Capacity of a Mare

Last Updated on May 27, 2020 by Allison Price

New to this breeding game and ever wonder how many foals your mare can have? It has also been my concern when I entered into the horse world. This article offers guidance for you as you have only started. We will discuss how many foals a mare is capable to give.

A mare is capable of giving birth to a foal depending on how early you started breeding her. If you started breeding earlier, you will be able to produce more foals. But mare’s fertility is affected by age. A mare can still foal up until her early 20’s. With 11 months of gestation, one foal per year will be born. In theory, if you breed a mare every year from 4 years old until 20 you could get 16 foals.

Breeding on Foal Heat

Mares have a gestation period for about 11 months. This a long pregnancy. Because of this, they must become pregnant again shortly after giving birth. In that way, they will be able to produce at about the same time each year. If an owner waits a month or two to re-breed, the mare’s foaling date will slip later in the spring each year. The mare will most likely need to take a year off to avoid producing a summer foal.

Most of the mares come into heat about a week after foaling. Many breeders take this opportunity to breed the mare to keep her on schedule for the next year. But there are advantages and disadvantages to this.


A mare that conceives after being bred on her foal heat will produce a foal about the same time the following year. Mares that settle in foal can be turned out with their newborn offspring. They can be taken off the broodmare manager’s list for breeding later in the spring. This pattern in followed year after year for most mares with no problem.


It potentially includes questions about the mare’s readiness. The availability of the stallion and poor conception rates are also disadvantages. This is true in cases where the mare had a difficult birth or a retained placenta. She may have inflammation, infection or fluids in the uterus may build up. Any tissue damage during the birth will need time to heal before re-breeding the mare.

Mares that begin to show signs of heat as early as five days after foaling have lesser chance to be pregnant. It is better to wait for ten or more days to allow the uterus to shrink, clear fluid, and become less inflamed. Turn them out to pasture for better uterine

recovery. Younger mares generally are more likely to conceive and less likely to abort than older ones.

Twinning in Horses

Everybody wants to get something for free. But having more is not always good. Two can be a problem when mares conceive twins. Other animals routinely give birth to many healthy offspring from one pregnancy. But horses are not designed to nourish two features and produce viable twin foals. Double pregnancy puts the mare and foals at risk. Good outcomes are rare.

Mares that carry twins often lose one or both embryos within the first weeks after breeding. These mares will usually come back into season later in the spring. Some mares conceive twins for several months before aborting halfway through the pregnancy. As a result, these mares lose a year of productivity. If both fetuses survive until term, there is a high chance that the mare will have a difficult delivery. This can result to death of one, two, or all three horses. When twins are born alive, one or both of them may be undersized or weak. The potential of maturing into productive animals is less. Like any sick foal, twins need intensive care most of the time.

Twin foals are generally not a bargain. Most breeders will ask the veterinarian to reduce the pregnancy to a single embryo. This happens if twins are detected. An examination is conducted 14 to 16 days after the mare has been bred. During this time, the veterinarian can crush the smaller embryo. They do this so that the mare will have a normal pregnancy. If twins are detected in later months, other methods can be used to remove a growing fetus. These procedures are more difficult and may cause the mare to abort the other fetus. An early post-breeding exam is important with twin pregnancies. It usually allows and helps the mare and the single foal to have a successful outcome.

Although having twins can sound great, this is not the reality for foals. It will only put the mare and both foals at risk. The productivity will reduce. We put them in danger if we push through with twin pregnancies just to raise many foals.

How Many Times Can a Horse Be Bred?

The pregnancy period of a mare is about 340 days, that means a mare can be bred once a year. But consider your mare’s recovery from pregnancy and lactation as well. You may breed your mare every other year. This is to give their bodies more time to fully recover.

You can start breeding your mare by about 4 years old and continue every year until they become too old. By doing this, your mare will be able to give birth to as many foals as she can. Horse’s fertility decreases as they become older. With this, it will be difficult for an

old mare to get pregnant. They can live until 25 to 30 years old, nearing 30 years old will be hard for them to become pregnant.


In general, it depends on how often you breed your mare. When you started foaling her will also affect the number of foals you can get. If it’s as early as when she is 4 years old, the least you can get is 16 foals. But if you breed her every other year, you can have at least 8 foals. Having them foal successfully in their past 20 depends on their physical heath. We must also be aware of their ovarian and uterine health because it will affect their pregnancy.

Allison Price
Allison Price

I’m Allison, born and raised in San Diego California, the earliest memory I have with horses was at my grandfather’s farm. I used to sit at the stable as a kid and hang out with my Papa while he was training the horses. When I was invited to watch a horse riding competition, I got so fascinated with riding!