Interviewing for a Leadership Role...Pregnant

I'm in the process of applying for a management promotion to VP and I just found out I'm pregnant (this was unexpected, but a very, very happy surprise)! I just started the interview process, and they expect to be finished with all of the rounds of interviews and an offer made and accepted by the 2nd week of May. The million dollar question - do I tell the hiring manager? I'm afraid it will hurt my chances, but I also think there will be some angry people if I don't tell them, then get the job, then go out on maternity leave. By the way, my company offers 6 months of maternity leave, and I plan on using all of it, so I will be in the role for 6 months, then on leave for 6 months. What is the right thing to do here? I really want this career opportunity.