Katuwal S, et al. - In this case-control study, researchers assessed 47,479 Finnish grand-multiparous (GM) females registered as having had at least 5 births before 2013 to quantify the influence of length of birth interval on the risk of breast cancer by subtype. They observed an increased risk of lobular breast cancer with greater intervals between the first and fifth births. They also noticed premenopausal women with a shorter interval (< 2 years) between the first and second birth had a higher risk of ductal cancer whereas longer intervals (3+ years) were correlated with reduced risk. No impact of spacing was seen between the second and fifth birth on the risk of ductal breast cancer.