asking for a friend

Emily
I'm asking this for one of my friends she is in the process of weaning her two year old off breastfeeding and is wanting to start taking birth control but she is worried that stopping breastfeeding and starting birth control will be two much hormonal change she stopped breast feeding at night and now she is only doing early morning and sometime in the afternoon any advice or tips on what she should do? I don't have any kids yet so I told her I would ask other moms