NEW YORK, NY - AUGUST 15: White House Chief of Staff Gen. John Kelly looks on as US President Donald Trump speaks following a meeting on infrastructure at... Drew Angerer The disconnect between the White Houseâs John Kelly and his boss
While many females will hold to a fairly steady schedule of coming into season about every six months, it can vary. Some girls will only come into heat once year, while others may even come into season every four months. However, these extra seasons are not always fertile.
Female dogs have their first estrus cycle -- known as coming on heat or being in season -- at around 6 to 7 months, though it can be as early as 4 months or as late as 2 years in some breeds and individuals. From then on, most bitches come on heat twice a year. During estrus, female dogs have a blood-stained discharge. Pro-Estrus Bleeding The first stage of estrus is pro-estrus, lasting 4 to 15 days, and a hormone called estrogen is produced causing changes in the bitches' wombs and vaginas in preparation for mating.