Skip to content

Which are your dog's fertile days?

Estimate your dog's fertile days and when her next heat is due, from the first day of bleeding. Indicative only: ovulation is confirmed by progesterone testing.

The day you first saw bleeding or swelling, not when she became receptive.

Preguntas frecuentes

Which are a dog's fertile days?
They usually fall between days 9 and 14 from the start of bleeding, but individual variation is enormous: some dogs ovulate on day 5 and others on day 20. That is why this is an indicative range and not a calendar.
How often does a dog come into heat?
Every 5 to 8 months, fairly regularly within the same animal. Large breeds tend towards the longer end of the interval.
How do I know for certain when she ovulates?
With a progesterone blood test, done by your vet. It is the only reliable method, and the one used when the mating genuinely matters. Any calculation from dates is an approximation.
Can she be bred on her first heat?
No. She has not finished growing, and a pregnancy at that point compromises her development. The usual recommendation is to wait until at least the second or third heat, and to have passed the breed's health tests first.