Sims won't try for baby

sometimes if you save a game when sims sleep in a bed the bed gets bugged and thinks the sim is still in bed, if you delete the bed in build mode and than click the undo button it will sometimes reset the bed and make it useable again. Also make sure all doors and steps are not blocked by objects like the projects on the floor from schools, If you have seasons and have holidays with the gnomes active they may be spawning in the place your sim wants to walk to, but can't complain because game don't know the path is blocked, wait until holiday is over than try again. Sometimes if a diary is in the bed it may have gotten repositioned so that the book is interfering with woohoo. Remove the diary from the bed and try again. If the grim reaper is on the lot or the gnome that looks like death will also sometimes prevent woohoo. Make sure no other sims are pregnant in your household or woohooing at the same time, I tried that once and I got puzzled results one try for baby would fail and the other would succeed passed on who got done first, since a pregnant sim can have up to 3 kids at once, it blocks the others in the house from having kids until the sim that is pregnant has the kid or kids.