Disclosure in an interview about children??

So I’m about to get back into work and my partner and I are discussing trying for a baby in the next couple of years.

As I fully intend on staying in the job long term do I disclose that I’m wanting a family or not?

Part of me wants them to know so that they are prepared and I don’t end up out of a job when I do become pregnant (I know it’s not right for employers to let women go but the fact is it does happen)

But on the other hand I don’t want employers to purposely not employ me because of this.

Maybe I’m being negative about employers but I guess I’ve just had bad experiences.

So do you recommend I tell them or not? I’ve had managers ask about my 5 years plan before at interview.