New baby on the way

The other day I applied for a job and they told me I would hear something within the next week. I am almost 5 months pregnant with our second child and I was hoping to take 2 to 3 months off work. Do I tell this place that I am pregnant and hope they are ok with it a d hope that I will still get the job? I will be working with them for 4 months and the take those 2 to 3 months off to be with my baby. Or do I not say anything and then if I get the job say something and leave them for a bit? Its just a part time job and they dont offer maternity leave.