hmm, it's a hard one. after having dd, i really wanted to return to work - i had such a crap pregnancy, that i was desperate to get my life going again. (a difficult birth, a newborn & multiple mastitus was relaxing compared to pregnancy).
however, i also worked with someone who was very career focused, and right up til the moment her dd was born, was convinced she'd return to work within 3 months. apparently, one look at her child & she completely changed her mind.
so, you just can't tell how it will affect you emotionally or physically.
if you take the job further away, are you committed to it for a while - how easy will it be to climb the career ladder if you take the junior role? how easy is it for your dp to be a single parent (as he effectively will be 4 days a week) with things like the dc being ill, or finding childcare to cover his work hours?
personally, i found the time pressure trying to do a responsible job & trying to be a good mum was almost intolerable - dh worked longer hours & we had no family nearby, i never felt like i was doing a good job at work or home. as a result, i got no job satisfaction.
fwiw, you can take things easy for a few years, then 'kick start' your career again in your 40s & 50s. kids are harder to fit in later.