I have similar problem as Magestaff has except only 1 is esteemed elder, I used Time Warp on 1 mom (hoping to get runner) and she birthed baby fine but after that all mothers have carried babies to near death (or babies have born after mother has died) and oldest mother was 79 and still timer said 246 mins (I think) and due that mothers aren't gaining anny skills (2 has been trainees (parent and devotee) since they got pregnant days ago.

I haven't adjusted computer's time except few secs few times when I have checked that computer's clock is right and only paused for few secs many times to find children to pick up mushroom or collectible.

edit: I haven't used Grant Youth to carrying mother only older villagers who have devotee-skill (and 1 of those eternally carrying mothers is villager from begiinning who has Master Devotee-skill) or were close to become JOATs (3 or 4)or to get babies (previous + 5-6) due villagers living so long and being on pop-cap (not saying its a bug but atm avg age of death is 75-77 and maybe half dozen has died as 79 and at previous games some died earlier).