Our results indicate that PAO is a heterogeneous, rare but severe disease including a substantial number of fractures with a significant delay from first symptom to diagnose. Increased awareness is warranted to immediately start effective treatment.

Introduction Currently, osteoporosis research is rarely undertaken in males but an increase in male life expectancy in the company of hypogonadism suggests the necessity for potential therapeutic options. Materials and methods In this study, the changes in bone structure under standardized testosterone-(T), raloxifene-(R) and estrogen (E)-supplemented diets were analyzed in osteoporotic castrated male rats. Results Unexpected biomechanical results could be only explained by the histomorphometry, but not by BMD measurements obtained from the qCT. All tested substances showed a signiWcant improvement in the trabecular network (trabecular bone area for C: 2.55 mm 2 , T: 4.25 mm 2 , R: 4.22 mm 2 and E: 4.28 mm 2 ), and suggests that the bone structure was preserved. For the metaphyseal cortical bone, a signiWcant loss was detected in T (CBP: 18.7%) compared to R (CBP: 30.0%), E (CBP: 26.8%) and even to the osteoporotic control (CBP: 28.6%). This explains the observed early mechanical Wnal failure after T supplementation. However, due to the preserved trabecular bone in T, the occurrence of the Wrst microfractures (yL: 49 § 21.4 N) was signiWcantly later than in the osteoporotic control (yL: 39.5 § 15.5 N). Raloxifene performed well in hindering the bone loss associated with osteoporosis. However, its eVect (yL: 83.3 § 16.5 N) did not approach the protective eVect of E (yL: 99.2 § 21.1 N). Conclusion Testosterone only preserved the deterioration of the trabecular bone but not of the cortical bone. Raloxifene prevented the bone loss associated with osteoporosis at all bony structures. This eVect did not approach the protective eVect of estrogen on trabecular bone, but it is more suitable for male individuals because it has no feminizing eVects on the subject.

Our results support the hypothesis that pregnancy-associated TOH is a multifactorial disease, to which several individual factors may contribute. Hereby, we found significant associations with immobility, dental problems, and lack of exercise in childhood.

Our report demonstrates the successful use of teriparatide underlined by the increase of bone mineral density and the improvement of clinical symptoms in a case of severe pregnancy-associated osteoporosis for the first time.

Young primiparas who had a sedentary adolescence were at the highest risk of bone loss during pregnancy. Bone loss that occurred during pregnancy was typically recovered later on, based on unknown molecular and biochemical mechanisms that must be elucidated with further studies.