Chances are, this won't be an issue for you. You probably bought your ferret from a petstore pre-spayed. But sometimes ferrets spayed improperly, especially at an early age, can go into heat. This means that even your pet store ferret may experience the health problems going into heat intails.
But if you bought an un-fixed ferret, bought one from a petstore unfixed or from a breeder un-fixed , you'll need to have her spayed as soon as she's four months old. If she's older than that, have her spayed right away, if her health is up to it and if you can find a ferret experienced vet.
Spaying your female ferret is safe when done by a ferret experienced vet.
Please read Why wait? if you're wondering why.
A female can be spayed even after she goes into heat, but if she's been in heat for a month or more, your vet should do a blood test before the surgery. Females can be brought out of heat without becoming pregnant with a jill jab (hormone injection) or by breeding with a vasectomized male, either of which will lead to a false pregnancy which will last long enough to let her be spayed.
Hormone injections and vasectomied males are NOT an alternative to getting your ferret fixed. The 'Jill Jabs', in the long run, will cost much more than a simple spaying, and vasectomied males are occasionally able to impregnate a female. A local shelter had that problem with a young ferret female getting pregnant from a not-so-vasectomied male.
"Why should I spend all that money getting a fixed female?"
Unfixed ferrets are almost always cheaper. But even though fixing at 5 weeks (the standard petstore age for fixing) can be detremental to a ferret's long term health, it's infinatly better than loseing your female ferret to an unexpected heat. If you can't afford the price of a fixed ferret, you probably can't afford a ferret at all.
"Why fix my female ferret? My cat isn't fixed, and she does fine"
Ferrets have a long season which can last four to six months. But you wouldn't have to deal with it that long, because a prolonged heat of over a month will almost surely kill a female ferret without imediate medical attention.
Ferrets come out of heat by ovulating, and they only ovulate when they're either bred, or exposed to the chemicals breeding them releases.(a 'jill jab', a hormone needle)
Your female ferret may contract a desease through her weakened immune system, or a bacterial infection in her vaginal region, or she may become anemic from the constand blood flow to her uterus and vagina. Any way you slice it, a ferret in heat is a ferret in trouble.
"But I want to breed her! She won't stay in heat."
Ferrets are notoriously bad when it comes to pregnancies. There are so many things that can go wrong and that must be done specially for your ferret, and if they are not, you could lose a litter, or worse, your pet. Do you know what to do if her milk ducts are infected? Should she birth on a towel? These and many more questions can be life or death.
There are also too many ferrets in the population already. Litters of ferrets end up at ferret shelters every year, as well as pregnant females. Most ferret shelters have anywhere from 40 to 100 ferrets, and there are many shelters in every state. Do you know who to sell 4, or 10, or 45 ferrets to?
Finnally, besides her health, and overpopulation, male ferrets kept whole stink, are agressive to other ferrets to the point of sometimes killing them, and generally can't be kept as a running around housepet with your other ferrets.
Even one litter is too much.
Don't breed. Period.
If your ferret has a swollen vaginal opening, or has vaginal discharge, is unaturally thin, or seems to be wasting away all of a sudden, get her to the vet! She may be in heat, and will definatly need immediate medical attention
Anemic: Wasted away, lacking vigour or energy. Anemia: A deficency of red blood cells. In ferrets , it's the inability to regenerate enough blood in a prolonged heat Vagina: The passage leading to the uterus. In ferrets, this is right below the anus under the tail. When in heat,it will be swollen, red and shiny, and very noticable.
Heat: Also known as season, it is the time when a female animal is receptive to breeding and pregnancy.