@ Carole – I like yours and agree with Kate’s comments re: the Bible.

@ Emma – Your first version was too wordy but I think you’ve gone too far the other way and we’ve lost any emotional punch. Miscarriage, infidelity, a soon-to-be orphaned child – all these give us much more flavour of what we’ll be reading. Also your first sentence about Jemima being so focused on what she doesn’t have is very well-structured but makes me think of more material things, rather than something so profound as a miscarriage. Maybe something more like:
Jemima is struggling with loss – a pregnancy and possibly her marriage. She’s lost sight of what still matters but meeting 10 year old Saffi, who faces a truly bleak future, forces Jemima to reassess.

I hasten to add I am no expert and find writing elevator pitches really hard, so take what I suggest with a massive pinch of salt.