Cohen A, Kamanda-Kosseh M, Dempster DW, et al. - Given that pregnancy and lactation–associated osteoporosis (PLO) is a rare, severe, early form of osteoporosis where young women present with fractures, usually multiple vertebral fractures, during late pregnancy or lactation, researchers tested the assumption that clinical, bone structural, and metabolic traits would vary between women with PLO and those with (non-PLO) idiopathic osteoporosis and controls. Participants in the study were 78 women with low-trauma fractures and 40 healthy controls with normal menses and without secondary cause of bone loss. More fractures, more vertebral fractures, and higher prevalence of multiple fractures were seen in women with PLO. These women also had significantly lower tissue-level mineral apposition rate and bone formation rates, as well as lower serum P1NP and CTX than IOP. Findings suggested that women with PLO may have underlying osteoblast functional deficits that may influence their therapeutic reaction to osteoanabolic drugs.