Estrus cycle or the process of being in heat is a phenomena during which queen (female cat) is sexually active or is ready to mate. Through this process, cats produce their litter. It is a natural phenomena which is under the influence of hormones and is observed in during a several times in a season.
The stage usually lasts for 7 days but sometimes it may exceed to 14 days too.Usually your cat will come into its first heat at the age of 9 months but according to some literature it can be seen at 6 months too.
Your cat will mostly depict behavorial signs through which you can easily understand that she is on her heat
1)Extreme affectionate.Your cat will move around you, will rub her body against yours and will continuosly be asking for your attention.She will be rubbing her body against furniture,against inanimate objects or will be continuosly asking for owners attention.
2)She will be continuosly rolling on the floor
3)She will be vocalizing more than usual
4)When touched on their back,they will rear their hind or rear quarters into the air.
5)They will ask to go outside and this behavior is usually shown by sitting on the main entrance of their house by where they can see the male cats
6)They will urinate more frequently or they will urinate on vertical objects.Through their urine they leave their hormones or pheromones which attract the male cats
Usually these behaviors are very annoying to their owners
In this condition,you must arrange a tom to mate your female cat if you want a litter.In other case,where you dont want a litter and want to get rid of this, the best solution is to get your cat sterilized.The process is known as Spaying or Ovarian hysterectomy in which your cat is operated for not being in heat again but,this process can only be done when your cat is not in heat or if she is in heat, it is better to let the heat pass and wait fro another week and then go for this process.
A BIG NO is for anti heat injection which is actually a killer to your cat good health.