Endocrine Abstracts

Pregnancy Associated Osteoporosis (PAO) is a rare condition which typically presents with back pain and height loss due to the occurrence of multiple vertebral fractures. Although symptoms often occur towards the end of the third trimester, the diagnosis is usually made post-partum. The estimated prevalence of the condition is about 4 in 100,000 women. The diagnosis should be suspected in a woman who experiences back pain so severe as to interfere with normal activities accompanied by height loss. The cause is unknown. It has been speculated that PAO may occur as the result of physiological bone loss in women who have pre-existing low bone mineral density (BMD) before pregnancy, exaggerated physiological bone loss, or a combination of both factors. There is evidence for a genetic component due to the frequent observation that women have a family history of osteoporosis. There have been few studies in which genetic analysis has been conducted but those that have been performed suggest that about one third may have pathogenic variants in genes that regulate BMD or bone fragility. The diagnosis is usually can by a combination of spine x-ray, MRI and DEXA. Lumbar spine BMD is consistently lower than hip BMD in PAO, although it is not always possible to obtain spine BMD measurements due to the presence of vertebral fractures. The most used treatments for PAO are calcium and vitamin D supplements, bisphosphonates and teriparatide, although there is evidence that BMD improves even without treatment. The rate of recurrent fractures is about 12% and does not seem to be influenced by treatment. Further research is required to determine the cause of PAO, and to define the optimal mode of treatment to guide clinicians on how to manage this rare but serious disorder.