My husband made two sessions jacuzzi two consequent days, 1 hr length each, does this affect his sperm health? For how long will the harm persist?

See answer. Men's testes are outside the body for a reason: they need to be in cooler environment to produce healthy sperm. Can take 2-3 months to produce mature sperm cell and immature sperm are especially vulnerable. Hot tubs, saunas, etc are probably okay in moderation, but the more overheating and the more marginal the baseline sperm quality, the more adverse the effect. Best to avoid if pregnancy desired.