Signs of foaling in mares: How to recognize them

It can be an amazing or frustrating experience for you to be part of your mare’s foaling. Why is it this unpredictable? You never know when your mare is approaching her date unless you’ve experienced her pregnancy and foaling before. Therefore, all horse keepers must know the signs of foaling in mares to be well-prepared for a healthy parturition.

Stages of Horse Pregnancy You Should Know

Before switching to the signs of foaling, observing the mare and confirming the pregnancy is essential. Once your veterinarian has confirmed the pregnancy, you can take care of your horse.

The average gestation period of the horse is 340 ± 20 days. Similar to humans, horses also experience pregnancy divided into three trimesters.

  • You won’t feel visible changes in the belly shape of your mare in early pregnancy but can confirm a foal with ultrasound, per rectal examination, or various biochemical tests.
  • The fetus inside the mare’s womb will speed up development by the end of the first three months and ultrasound images may show the miniature horse on screen.
  • Because of the musculature buildup in horses, the mare appears to be pregnant after 6 6-month gestation period.
  • Your horse is ready to get the vaccinations and deworming after 114 days of pregnancy or after the beginning of the second trimester.
  • The diet chart is revised after the mare completes 7 months of pregnancy. Also, they refrain from putting her into a regular exercise routine.

You must deal with the last trimester under the supervision of veterinarians and with knowledge of signs of foaling in mares to eradicate the chances of inconvenience.

Signs of Foaling in Mares

You can anticipate the foaling time by seeing the physical and behavioral changes in the mare. The collected data from various mares shows they prefer nighttime for giving birth to baby horses. This makes horse keepers more concerned about tracking the estimated foaling date to make necessary arrangements.

1. Monitor the Mare in the Last Trimester

The delivery date can be anywhere between 320-360 days of the gestation period. There are several foaling date calculators available if you’re sure about the covering (mating) date of the mare. Here are some clues your mare will give you before foaling.

2. Mare Belly Before Foaling

The belly of the mare stretches by the end of 10 months of gestation, indicating foaling is near but not that much to panic about. But this is the time for the owners to observe it continuously up to the foaling. Followed by the stretch is the relaxation phase of the belly, making a ‘pendulum shape.’ This pendulum, or ‘V’ shape, signifies the turning of the fetus to reach the birth position.

You may observe the belly getting smaller with the time approaching to foal. It is because the fetus is shifting to the pelvic cavity from the abdominal, leaving the bulging behind. This may not be true for all the mares. Maiden mares require frequent observation and care throughout the pregnancy period.

3. Mare Bagging up Stages: Mammary Gland Development

Mares bag up before two weeks of foaling, which you can easily notice. You may also see the hardening and changing texture of the mammary glands 4-6 weeks before foaling. The fullness of the udder signifies the tissue has formed milk required by the born foal.

In 95% of the pregnant mares, the teats secrete a wax-like substance before 6-48 hours of foaling. This is called the waxing on the teats. In some instances, this sign can come days before foaling.

4. Behavioral Signs in Mares Near to Foaling

Mares exhibit restless behavior before giving birth. She might walk more or change positions more than usual. If you know her normal posture, you can suspect the shift in the tail as the contractions increase.

Sudden loss of appetite and frequent urination are also significant. With time approaching foaling, the mare would look at her belly or flank more often. She will isolate herself and show nesting behavior.

These signs are alarming for you to begin with the preliminary preparations for her.

5. Relaxation of the Pelvis Area

Mares undergo several physiological changes before parturition, and pelvic relaxation is one of them. Relaxin hormone produced during late pregnancy facilitates the pathway for the birth of the fetus by softening the uterus and pelvic muscles.

You can feel this change before three weeks of foaling. If you lift the tail of the mare, you’ll feel less resistance because of the start of the relaxation of muscles around the tail region.

You can also see the lengthening of the perineum, which includes the anus and vulva. Usually, the vulva isn’t this elongated and has wrinkles in the surrounding skin. The vulva relaxes before foaling, showing elasticity.


Q 1. How soon do mares bag up before foaling?

Ans: Most of the mares show bagging up 2 weeks before foaling. This is when the mammary gland prepares for milking and appears full. In some mares, the change in the udder's size is visible before the 4-6 weeks of foaling.

Q 2. How do mares behave before foaling?

Ans: The mare will try to isolate herself from the herd. It will appear restless while approaching foaling. You may see her often going to recumbency and getting up. Tail raising and nesting behavior are the other signs of foaling in mares.

Q 3. How many days after pregnancy does a mare foal?

Ans: The mare foals anywhere between 340 ± 20 on completion of gestation period. In the last month of pregnancy, the mare will show significant signs like changes in belly shape, bagging up, relaxing of pelvic muscles, and lengthening of the vulva as signs of foaling.


The average gestation length in horses is 340 days. There are some specific signs to understand your mare is near to foaling. The mix of behavioral and physiological changes marks the beginning of the end of pregnancy. The significant pendulous belly shape in the last month of gestation will denote the fetus turning.

There are different stages of bagging up which start 2-4 weeks before foaling, showing fullness of the udder and she may drip the milk a week before foaling. Waxing on the teats is a significant sign that appears 6-48 hours before the foaling in mares.

You must see your vet in the last trimester of the mare’s pregnancy along with knowing these signs of foaling.


Dr Akanksha Agnihotri is another animal lover like you cum veterinarian by profession. She has earned her B.V.Sc & AH from COVS & AH, Jabalpur, India. She has a knack for befriending animals/pets and treating them compassionately. She believes...