Yes, it may happen, although the extent to which breast size increases depends on the woman and the birth control method used. Estrogen and progestin can cause you to experience an increase in breast size, but it generally reverses after a few cycles or when the woman stops using them. This side effect is often accompanied by breast tenderness (i.e. mastalgia).
Can hormonal contraceptives lead to breast tissue growth?
By Andrea Rodrigo B.Sc., M.Sc. (embryologist).
Last Update: 12/07/2016
Bachelor's Degree in Biotechnology from the Polytechnic University of Valencia. Master's Degree in Biotechnology of Human Assisted Reproduction from the University of Valencia along with the Valencian Infertility Institute (IVI). Postgraduate course in Medical Genetics.