question!! started seasonal job

katie
I just started a seasonal job working from home! it's an amazing job and I love it so far but I'm 25 weeks pregnant & haven't told them! I was hired to work "until the position or season ends (January 31st) whichever comes first". When I did the interview I asked when the position would end and she said "at the end of the year." my due date is December 28th so I figured that was pretty perfect. but now they're saying the position will end when "business demands" deem necessary. so I'm unsure of how to approach the situation. I obviously want to speak with HR and I know that's the first step but I'm so nervous! I want to remain rehire-able at the end of the season so when baby is a little older I can go back!! any advice would be amazing. thank you!!