Hi
I don't think I would.
My partner and I were interviewed the same day by the same people for different jobs at the same company, oddly enough he was asked no questions about his plans to start a family but I was. I was quite vague, I said I was hoping to buy a house first... I'm also hoping to win the lottery first! I only stayed there for a couple of months but was also asked about my plans for a family in the job I'm at now and said the same.
I have just under 2 months of my probationary period left (6 months in total) and am now 7 weeks pregnant. I'm waiting to tell anyone at work until this date has passed, that's the plan anyway.
Good luck with what happens
Vicky