 European hares have a prolonged breeding season which lasts from January to August . Sexual maturity occurs at seven or eight months for females and six months for males . Females , or does , can be found pregnant in all breeding months and males , or bucks , are fertile all year round except during October and November . After autumn , the resting period for breeding activity , the size and activity of the males ' testes increase , signalling the start of a new reproductive cycle . This continues through December , January and February and the reproductive tract gains back its functionality . Matings start before ovulation with the first pregnancies containing one foetus and pregnancy failures being common . Full reproductive activity begins in March and April , when all the females may become pregnant , the majority with three or more foetuses . 
