Things to consider before breeding a horse are the cost, the health and quality of the horse being bred and risks caused by the birthing process. Caring for the mare during pregnancy is also a responsibility that needs to be thought about.
Breeding a mare to a high quality stallion can cost up to several thousand dollars, as of 2015. Veterinarian expenses before and after breading are likely, and many stallion farms charge for taking care of the mare while the attempted breeding takes place. It also costs money to raise a new horse for four years from birth. Only mares and stallions that have proven physical and mental qualities should be considered for breeding. Breeding unchecked horses is irresponsible and can produce undesirable results. A horse owner must also understand that breeding a horse isn't cloning it, there are no guarantees for color or size of the foal.
Pregnant mares require special feeding half way through the gestation period. Owners must decrease the work load for pregnant mares. Around nine months into the pregnancy, the mare should only be ridden lightly or not at all. Regular veterinarian checks may be necessary, and the mare requires a stall large enough for her and the foal. Heavy monitoring before the due date is highly recommended, and someone needs to be there for the birthing process in case of emergency situations.