No real cause, just an impending Estrus cycle.
Increased body temperature and libido, cramping and irritability, increased slick flow and more nesting behavior.
If an Omega chooses to not go through their cycle, they can take suppressants to remain in pre-Estrus for its duration. If they choose not to. they will continue to go through the cycle into Estrus proper. In Estrus proper, treatment includes knotting (whether through toys or an actual alpha), and a good nest/satisfying mate.
In Pre-Estrus, the omega will begin to experience cramps and irritability as well as a stronger scent. This stage endures for a couple of days. The next stage includes nesting and increased libido in which the omega will begin to attract sires. The condition ends in Estrus Proper.
No pathological conditions, though akin to nymphomania can occur in omegas going through Estrus on the whole.
Omegas, though Betas can go through it if the population suffers from a surplus of alphas. For half-orcs, Pre-estrus accompanies a monthly estrus proper, similar to the menstrual cycles of human and elf women.
Suppressants or pregnancy.
Dams have been gong through heats since the beginning of time.
Typically respected. Individuals going through Estrus on the whole are taken care by pack or clan in great detail.