When to spay or neuter a cat: age and benefits

Cats can be spayed (females) or castrated (males) from around 4 months of age in the UK and most of Europe, though timing recommendations vary slightly by country and vet.

Why the timing matters for females

Female cats that are spayed before their first season have a dramatically reduced risk of mammary tumours — the most common malignant tumour in female cats. Neutering before the first season reduces risk by ~91%; after one season, the benefit drops to ~86%; after two seasons, ~11%. There is little protective effect after 2 seasons.

Cats can come into their first season as early as 4–5 months, particularly in spring. A cat that goes outdoors can become pregnant very young.

Benefits of neutering for both sexes

- Females: eliminates pyometra (life-threatening womb infection), prevents unwanted pregnancies, reduces mammary tumour risk, ends heat cycles (which are frequent and can be distressing — cats in heat call loudly and spray).
- Males: eliminates risk of testicular cancer, reduces urine spraying, reduces roaming and fighting (which reduces abscess and FIV transmission risk), and eliminates the pungent smell of intact male cat urine.

Does neutering change a cat''s personality?

It reduces hormone-driven behaviours (roaming, spraying, calling) but does not change a cat''s fundamental personality or affection level.

Does neutering cause weight gain?

Neutered cats have lower energy requirements. Without a reduction in food intake, weight gain is common. Transition to a neutered cat formula food and monitor body condition monthly. Flovvi''s weight log makes this easy.

Post-operative care

Females are usually kept overnight. Males go home the same day. Both need 7–10 days of restricted activity and an E-collar to prevent licking stitches.