
When a woman orgasms, her cervix opens and "suctions" slightly with the pulsating of the orgasm, as the kegel muscles contract to help pull the penis in farther. If it all possible for you two, and especially if you know you're ovulating, timing your orgasm so that it happens for you WHILE or IMMEDIATELY after it happens for him will give you the best chance of getting those little suckers up in there. Just a heads up.