Foreplay and him ???

Okay so with blowjobs as a form a foreplay, do you ladies continue until he finishes, or stop before and then have sex afterwards? Or either way have sex after you suck him?
I'm newly getting into them with my boyfriend (but I do love giving them) so I want to incoporate them into our sex, because as I sort of see it, if I make him cum he won't be able to have sex straight away after? Or atleast not for a while? 
Any help ladies?!