i only know the cheat for twins. Open the cheat box ( ctrl shift C) then type forcetwins or force twins... you can type cheats for twins for the sims 2 for PC in google - that always helps me.

Also, try having the baby over and over e.g. say ur about to have the baby, then save then play if you get a boy but want a girl, just dont save progress and re-open the lot til u get the girl coz the babys gender changes.

to berrieshakes81: thanks!! Ill try it! ; )

ok people thanks!!!

There isn't a cheat for choosing the gender, but if you type in forcetwins, it will make you have twins next time you have a baby.
Sorry if i wasn't much help.

if ur sim is pregnant, type forcetwinz