I have started a temp job in June, the contract is for 3 months. 2 weeks after I started, I found out I was about 4 weeks pregnant. One of my colleagues has since gone on maternity leave, and the boss is constantly telling me I mustn't get pregnant, and has asked if my boyfriend and I are planning to get married etc. We are in fact getting married in September, but I told my boss we have no such plans and that I'm not pregnant.
Now they want to extend my contract until end of next year. I am planning to tell them about the pregnancy once they officially offer me an extension. My problem is, I have so far denied the pregnancy and marriage intentions. I'm worried the boss and the rest of the team will resent me, once they find out. I have miscarried before, at around 4 months, so I was hoping to keep the pregnancy to myself until then, but I don't think that would be fair on my employer. My employer is a HUGE institution, so I'm sure they'll find a replacement for me quickly, I just don't want to work for 5-6 months in a bad atmosphere.
What should I do? Should I tell them about pregnancy even before the offer? Or can I keep quiet until 15 weeks before due date? My boss is quite moody and very scary :(