How many times a year does a female dog go into heat and for how long?

• A. Twice per year for 60 days
• B. Once per year for 30 days
• C. Three times per year for 5 days
• D. Two times per year for 2 days to 20 days

Answer: (D)

A female dog’s heat cycle occurs roughly twice a year, about every six months, and the heat phase lasts about two weeks on average, though it can vary from a couple of days to around three weeks. So describing it as two times per year for a period of 2 days up to about 20 days captures this typical pattern, including the variability in duration. The other options misstate either how often it happens or how long the heat lasts: one year with a 60-day heat is unusually long, three times a year is more frequent than normal, and a single annual heat is not aligned with common canine biology.