We examine early life factors associated with breast cancer subtypes.
Advanced maternal age at birth seems to be positively associated with HR+ tumors.
Taller girls present higher risk of postmenopausal BC and HR+ tumors.
Thinner girls show and excess of postmenopausal BC, particularly HR+ and TN tumors.
Heavier girls before puberty have lower risk of premenopausal BC and ERB2+ tumors.