New job offer at 7 weeks - advice please!

Just looking for some more words of wisdom. I'm struggling to make a decision! I've been offered a new job for a company I really want to work for but I'm 7 weeks pregnant (so still super early!). I've had the contract through so I'm planning on telling them I'm pregnant before I start. But I also have the option to stay in my current job (which I really dislike). I would qualify for enhanced mat pay if I stay, and I guess it would be slightly less demanding as I can keep under the radar. New job major pro is I can do a job I like, but would only get less than half the mat pay. It's only a 1 year position (in my field it is very common for short fixed term contracts) so I would have no job to go back to. Has anyone been in a similar position or can give me some objective advice?! Thank you :)