The association between parity, age at first pregnancy, breastfeeding and breast cancer risk in Europe. A systematic review and meta-analysis

Abstract

The association between breast cancer and reproductive factors have been declared by various designs, yet the approaches utilized in meta-analyses for case-control studies have been recently argued, in addition to studying the association between reproductive factors and breast cancer risk merely utilizing never/ever comparisons for recruited studies. This meta-analysis studies the association between breast cancer risk and reproductive factors (parity, age at first pregnancy, breast-feeding) by detailed levels.