Reproductive Health & Neutering
Understanding a dog’s season
Typical patterns vary between dogs. Averages are useful context, not a timetable for your dog.
Why it happens
Ovarian hormones prepare the body for reproduction. “In season” usually refers to proestrus and oestrus, the first two stages of the cycle.
First season and frequency
The first season often occurs between 6 and 24 months, sometimes later in large breeds. Small dogs commonly start earlier. Many dogs cycle roughly twice a year; some breeds have longer intervals. Young dogs may have irregular early cycles. Ask your veterinarian about absent, unusually frequent or persistently irregular seasons rather than assuming a breed average explains them.
Duration
Visible season signs commonly last about 2–4 weeks. Bleeding need not last throughout. Individual phases vary considerably, so neither this range nor the end of visible signs confirms that fertility has ended. Record observations and ask the practice about your dog’s pattern.
Do not predict fertile days
A tracker cannot determine fertility, establish a safe mating date or replace veterinary assessment. Do not use bleeding, its cessation or calendar estimates to decide that mating is safe.
Choose a short guide
Evidence and review
About this guidanceReview details and sources
Evidence and review
Evidence assessed 8 October 2026. General owner information, not diagnosis or individual treatment. Practical care suggestions are editorial guidance. Independent veterinary and native-language review has not been obtained. References do not imply endorsement. Existing linked pages retain their own evidence-review dates.