Telling landlord/estate agent I’m pregnant?

I’m 23 weeks pregnant with my first baby, due in March, and privately renting a 2 bed house with my husband - we’ve been here for about 18months. The estate agent emailed us March this year and said the landlord had offered us another 12months fixed tenancy agreement at the same rent, which we accepted - we are very happy here! And this finishes in May this year. I wanted to ask if anyone was in a similar situation and had past experiences of telling landlords/letting agents they were pregnant? I’ve had a look at our tenancy agreement and there’s nothing about children/babies not being permitted. The house was advertised as being suitable for couples/small families. The agreement states something along the lines of if anyone else comes to reside at the house we’d need to let them know and this would need to be approved in writing, but then it goes on to talk about immigration checks/right to rent, so not sure it’s applicable to a baby? It seems like a bit of a grey area - we are good tenants, both working/professional jobs and the rent is always paid. We’d love to stay in the house for another year or so until we know what we are wanting to do longer term. I’m just terrified we will let the landlord know and they won’t be keen on a baby being in the house/worry about the rent not being paid with me being on leave, and not extend or renew the tenancy agreement as they did this year with us and we would have to move. Or they’d not be happy with us suddenly springing on them that there’s a baby in the house and a new tiny resident. Anyone got any advice?!