Do I Have a Pregnant Horse? Here's What You Should Know About Pregnancy in Horses

April 15, 2021

Do you wonder if you have a pregnant horse? Pregnancy in horses lasts almost a year, but it can be hard to tell for the first several months.  

There are several old wives' tales out there about how you can know if your horse is pregnant — these don't work, so don't try them.  

In this article, we'll cover the dos and the don'ts of figuring out if your mare is pregnant and the signs of pregnancy in horses. Then, we'll go over the gestational period and best practices to care for the mare until she gives birth. Keep reading to learn how to know if your mare is pregnant or how to take care of her. 

What NOT to Do If You Think Your Horse Is Pregnant

One of the first ways you may hear to determine pregnancy in horses is to “do nothing.” The logic behind this is that nature has thrived on its own for millions of years. However, leaving your horse alone when she could be pregnant doesn't always lead to the best outcomes. Mares with high-risk horse pregnancy can develop medical problems that put the mother and developing foal in danger.

There are tons of folk methods that many people claim to work when trying to confirm a horse pregnancy. These claims are dangerous because they're unfounded and can give a false answer.

Some of these methods for figuring out pregnancy in horses that you should AVOID:

• Holding a threaded needle, ring, or nail on a string over the horse's stomach
• Seeing if the mare shakes her body and not just her head and neck
• Lack of a heat cycle (some mares can still go in heat despite being pregnant without showing any signs of heat)
• Looking at the horse stomach for growth or bloating

While it may be tempting to try one of the folk methods above to figure out whether your horse is pregnant, they're old wives' tales and don't hold up. 

Instead, determine if your horse is pregnant the right way.

What To Do If You Think Your Horse Is Pregnant

If you want to know for sure if you're dealing with a pregnant horse, there's only one surefire way to it: bring your horse to their veterinarian. Ideally, you will have a vet that specializes in equine care and horse pregnancy specifically.

If you've bred the mare, you should take her for this appointment about two weeks after the breeding date. If you did not breed her but suspect she is pregnant, get her seen by a vet as soon as possible.

After two to three weeks, a vet can determine pregnancy in horses using medical imaging. They can also tell you if the horse is pregnant with twins or not pregnant at all. It's essential to know her status early on for the best chances of normal development.

You should plan to have the mare checked again forty days after breeding. An ultrasound at this stage can determine if the uterine development is normal by looking for endometrial cups. At this stage, these cups attach to the placental formation around the uterus. If the mare loses the pregnancy after this, the cups will remain, making the mare unfit for breeding for 120. Therefore, the 40-day exam is critical. 

About the Horse Gestational Period

The gestation period for a pregnant horse can be anywhere between 320-380 days.  Understanding the gestational process will help you best care for your mare through feeding and management. 

Here are a few basic facts about pregnancy in horses:

• A mare can only have one horse pregnancy per year.
• A mare can become pregnant as early as 18 months old.
• Ideally, a mare would be at least four years old before becoming pregnant.
• Ponies' gestational period is shorter than for adult orses.
• Mares go into heat every three weeks or so during the spring and summer.

It can be hard to identify pregnancy in horses early on in the process, but once the mare becomes about six months pregnant, you may be able to tell visibly. 

Around six months of pregnancy in horses, the mare's stomach may become visibly larger. If the horse has had a foal before, their stomach may expand earlier than a horse that hasn't. As they approach the birth, the pregnant horse's stomach will continue to grow larger as the fetus grows inside her uterus. 

When you get about two weeks away from her due date, her udders will begin to produce a fluid that is a bit sticky and yellow, and they will swell. 

Signs and Stages of Foaling

When they've reached about 315 days of horse pregnancy, you should start to keep a close watch on the horse to catch any signs of birthing. There are a few signs of foaling that you can start to look for:

• The yellow liquid will turn white as it becomes colostrum or first milk
• The horse's belly may drop lower as the foal moves into its proper birthing position

If you notice one or both of these signs, you should start to prepare for the birth. Check on your pregnant horse frequently until the birth begins, so you can bring a veterinarian on-site when it happens.

As labor begins, the mare may show signs of distress or restlessness. She may start checking the sides of her body or pawing at the ground with her hooves.

At this point, the pregnant horse should move into a large, clean stall bedded with straw. The horse may start to switch between lying down and standing up, but she will lie back down when it's time to give birth.

If the mare shows signs of dystocia, it may experience a breech birth. In this case, the foal comes with its hindquarters out first or with bent legs. It's critical to have a professional available in case this occurs.

Managing a Pregnant Horse

Now that you know everything you should expect from pregnancy in horses, let's go over the proper management and care for a pregnant horse. 

Once you have confirmed the horse pregnancy, you can start to make adjustments to your feeding and care schedule to best support the mare.

Diet

If the pasture she currently grazes in is fescues, then you may want to move her to a different location during her horse pregnancy. She needs access to the best-quality hay or grass and enough salt and minerals in her diet.

Riding and Exercise

Too many owners falsely believe that riding or exercising a pregnant horse is terrible for them and could be dangerous to the horse pregnancy. If the mare is generally healthy and the vet does not categorize her horse pregnancy as “high-risk,” it would be good for her to get some exercise. 

You can continue regular rides and workouts with her until she's eight months pregnant or as long as your vet continues to say that it's okay. 

You should still try to be light on the exercise during the first three months to promote proper development in the earliest stages of horse pregnancy.

Social Life and Housing

If you have any other horses who can be bullies, it may be a good idea to separate the mare from them to keep her safe from injury.

However, you shouldn't isolate the mare during her horse pregnancy. She needs fresh air, space to graze, and a few compatible pasture-mates, if possible. 

You can keep her with a group of friendly horses, but toward the end, it's a good idea to keep her in a stall at night to prevent the chance of her giving birth outside, where cold weather or harsh winds could put them in danger. 

Health Care 

It's essential to keep up with your mare's necessary vaccination and de-worming doses, but you should hold off on these during the first three months of gestation. These medications may interfere with fetal development. You should always talk to your doctor about what is safe to give your horse while pregnant.

You need to know that there will be additional costs to having a pregnant horse. However, the cost is much less than the cost of potentially losing that foal or the mare herself.

Pregnancy in Horses — The Bottom Line

When you are dealing with horse pregnancy, don't fall for old wives' tales. The only way to medically prove that a horse is pregnant is through a professional veterinarian examination or ultrasound.

Once you have confirmed the horse pregnancy, use some of the tips we shared above, like improving her diet and keeping her away from bully horses to ensure a safe and smooth pregnancy.

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