Groups.cache and contentregistry yes, the rest I'm not sure. There is a list of cache files you can delete here:
http://www.modthesims2.com/wiki.php?title=Game_Help:Delete_Cache_FilesAs to pregnant women, I'm not an expert so the only way I now of is the using the function on the insimentor download that you get here at this site. Someone else who knows more, feel free to add to this but I hope that helps a little.