Female French Bulldogs typically go into heat for the first time between the ages of 6 and 12 months. However, some French Bulldogs may go into heat earlier or later than this. The estrus cycle typically lasts for about 21 days, but it can vary from 18 to 24 days.
During the estrus cycle, female French Bulldogs will go through several stages:
* Proestrus: This is the first stage of the estrus cycle and it typically lasts for about 9 days. During proestrus, the female French Bulldog's body will begin to prepare for ovulation. She may experience some vaginal bleeding and swelling of the vulva.
* Estrus: This is the second stage of the estrus cycle and it typically lasts for about 9 days. During estrus, the female French Bulldog will be fertile and able to reproduce. She will release an egg from her ovary and she will be attracted to male dogs.
* Diestrus: This is the third and final stage of the estrus cycle and it typically lasts for about 12 days. During diestrus, the female French Bulldog's body will begin to return to normal after ovulation. She may experience some vaginal discharge and her vulva will return to its normal size.
After the diestrus stage is complete, the female French Bulldog will enter a period of anestrus, which is the time between heat cycles. The anestrus period typically lasts for about 4 months, but it can vary from 2 to 6 months.
It is important to note that female French Bulldogs can become pregnant even if they are not showing any signs of heat. This is because ovulation can occur before or after the estrus stage. Therefore, it is important to keep female French Bulldogs away from male dogs during all stages of the estrus cycle unless you intend to breed her.