Pregnancy and Lactation Associated Osteoporosis: A Systematic Review

Pregnancy and lactation-associated osteoporosis (PLO) is a rare disease. It represents a challenge for physicians for diagnosis, treatment and follow up. Our aim is to review fracture data in women with PLO presenting with fragility fractures occurring during late pregnancy or the postpartum/lactation period. We conducted a comprehensive literature search of the following databases: PubMed, MEDLINE and EMBASE from inception until October 2024. We included observational studies and placebo arms of interventional studies assessing fragility fractures at any site among reproductive-age women (18-50 years) during pregnancy, lactation, or up to one year postpartum. We abstracted data and assessed the quality of the included studies in duplicate and independently. We identified 11,375 citations in total, screened 329 full text articles, and included 17 papers from 12 original articles. The mean ± standard deviation (SD) age of women with PLO and fractures in the included studies ranged from 30.6 ± 3.3 to 39.5 ± 6 years. The mean ± SD BMI at the time of diagnosis ranged from 20.9 ± 1.9 to 23.9 ± 3.7 kg/m². In women with PLO, there was no clear association with the age at menarche, while being primiparous seemed a common yet inconsistent finding. While most reported fractures occur during lactation, evidence on whether lactation characteristics such as intensity, duration, and exclusivity modify fracture risk remains inconclusive. Around one third of women with PLO have family history of osteoporosis. Vertebral fractures are the most common fractures, specifically in the thoracolumbar spine. The mean ± SD number of vertebral fractures ranged from 3.3 ± 3.4 to 5.5 ± 3.3 per patient. The risk of fracture recurrence in subsequent pregnancies ranged between 7 and 28% in the included cohorts. We identified limited data on the beneficial impact and adverse events of anti-resorptive and anabolic therapy in women with PLO. PLO is a debilitating disorder in young women with scarce data on predictors and for evidence-based treatment strategies. Further prospective studies with control groups are needed.