Foaling is the process by which a mare gives birth to her foal. It is one of the most significant events in a breeding horse’s year — typically fast-moving, often occurring in the middle of the night, and requiring prompt human intervention if complications arise. Understanding the stages of a normal foaling, the warning signs of a difficult birth, and the immediate post-birth priorities is essential knowledge for anyone involved in horse breeding.
The Gestation Period
The average equine gestation is approximately 340 days, or just over 11 months, though normal variation spans 320–370 days. Mares in the Southern Hemisphere tend to foal in late spring and summer (October–January); in the Northern Hemisphere, the natural foaling season peaks between April and June, triggered by increasing day length. Thoroughbred stud books in most countries use a universal birthday of 1 January in the Northern Hemisphere, which creates commercial pressure to breed early — February and March foals — resulting in foaling in cold conditions that require careful management.
In the weeks before foaling, the mare undergoes observable changes. The udder begins filling with milk — “bagging up” — typically two to four weeks before foaling. The muscles around the tailhead and hindquarters relax visibly as the birth canal prepares. “Waxing” — a waxy deposit of dried colostrum at the teat ends — typically appears 12–24 hours before foaling, though not all mares show this sign consistently. Some mares drip or run milk before foaling, which is a concern as it may indicate colostrum is being lost before the foal can drink it.
Stages of Normal Foaling
Stage One: Preparation
The first stage involves cervical dilation and repositioning of the foal for delivery. The mare becomes restless, may show signs similar to colic — getting up and down, looking at her flanks, sweating — and often goes off her feed. This stage can last from 30 minutes to several hours. The mare may appear to start and stop, particularly if disturbed; mares are well-known for delaying foaling if they feel observed or unsettled.
Stage Two: Active Delivery
Stage two begins when the amnion (white, pearly membrane) appears at the vulva. Normal presentation is “diving position” — foal facing downward, front hooves first with the soles facing down, one slightly ahead of the other, with the head resting on the forelegs. The entire stage two delivery should take no longer than 20–30 minutes in a normal birth. If it extends beyond 30 minutes without progress, veterinary assistance is needed immediately — a prolonged stage two poses serious risk to both mare and foal.
The foal emerges in its amnion sac, which usually ruptures during delivery. If the foal is born still in an intact sac, the membrane covering the nostrils must be broken immediately to allow breathing. Most mares foal lying down; once the foal is on the ground, allow the mare to rest quietly. The umbilical cord will sever naturally when the mare stands or the foal moves — do not cut or break it prematurely as significant blood transfer from placenta to foal continues in the minutes after birth.
Stage Three: Placenta Passage
The placenta should be passed within three hours of foaling. Retain and examine it — any missing pieces suggest retained placenta, which is a veterinary emergency. A mare that has not passed the placenta within three hours requires veterinary attention. Do not attempt to pull the placenta manually; this risks tearing and leaving retained tissue. Tie the placenta up in a bundle against the mare’s hocks to prevent her from standing on it and tearing it until it passes naturally.
The Foal’s First Hours
The first hours of life follow the “1-2-3 rule”: the foal should stand within one hour of birth, nurse within two hours, and the mare should pass the placenta within three hours. These benchmarks are practical targets. A foal that has not nursed within two hours risks missing the critical window for colostrum absorption — the foal’s gut can absorb maternal antibodies for approximately 12–18 hours after birth, after which the gut wall closes.
Colostrum is the first milk, rich in immunoglobulins that provide the foal with passive immunity until its own immune system matures. If a foal cannot nurse naturally, colostrum can be collected from the mare and bottle-fed. Foal blood IgG levels can be checked by a vet at 18–24 hours to confirm adequate passive transfer. Failure of passive transfer significantly elevates the foal’s infection risk in the first weeks of life. For more on the broodmare management context, see the entry on broodmare band.
Common Complications
Red bag delivery — where the thick, red chorioallantois presents at the vulva rather than the translucent amnion — indicates premature placental separation. This is a serious emergency. The bag must be cut immediately and the foal delivered as quickly as possible, as the foal is being deprived of oxygen. Any horse keeper who breeds mares should know how to recognise and respond to a red bag.
Dystocia (malpresentation) — where the foal is incorrectly positioned — requires veterinary manipulation. Posterior presentation (hind-end first) is potentially viable but requires urgent assistance. Head-back or leg-back presentations cannot deliver naturally and require manual correction or, in extremis, Caesarean section.
Frequently Asked Questions
How do I know when my mare is about to foal?
The most reliable indicators are waxing, active milk running, and the mare becoming increasingly restless and unsettled. Foaling alarm systems — either wearable devices that detect the mare lying flat, or cameras with monitoring apps — are widely used. The Foalert and Equine Alert systems are popular commercial options that alert you by text or alarm when the mare lies flat and begins stage two contractions.
Do I need a vet present for a normal foaling?
Not necessarily, but you should have your vet’s emergency number immediately to hand. A normal foaling is quick — 20 minutes from membranes to foal on the ground — and typically requires nothing more than observation. However, problems can escalate in minutes, and the difference between a living foal and a lost one can be the speed with which you identify an abnormality and get professional help.
What should I have prepared for foaling?
A clean, well-bedded foaling box of at least 4m x 4m; clean water and warm water for washing; clean towels; iodine spray for the naval stump; headcollar and lead rope for handling the foal; your vet’s number; and ideally a foaling kit containing clean gloves, scissors, and a bottle with teat in case the foal needs supplementary feeding. Many breeders also keep frozen colostrum from a previous foaling in the freezer as insurance.