Nandrolone Decanoate for Postmenopausal Osteoporosis: A Systematic Review and Meta-Analysis of Randomized Trials.

Postmenopausal osteoporosis is often accompanied by reduced muscle mass and chronic bone pain, amplifying fracture risk and functional decline. Nandrolone decanoate (ND), a synthetic anabolic steroid, has been proposed as a dual-acting agent that may benefit both bone and muscle through osteoanabolic and myoanabolic mechanisms, yet its therapeutic value in osteoporosis remains uncertain. We conducted a systematic review and meta-analysis of randomized controlled trials comparing ND with placebo in postmenopausal women with primary osteoporosis. The review followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines and was prospectively registered in the International Prospective Register of Systematic Reviews (PROSPERO; CRD420251147647). Seven trials with 293 participants were included, with sample sizes varying by outcome. ND reduced fracture risk compared with placebo (moderate-certainty evidence). It produced modest increases in bone mineral density (BMD; low certainty) and more substantial gains in forearm bone mineral content (BMC; moderate certainty). ND also reduced pain (moderate certainty) and increased muscle mass (moderate certainty). However, ND was associated with a higher incidence of mostly mild virilizing adverse events (hirsutism, acne, voice changes; low certainty). Given the small sample sizes and methodological limitations of older trials, ND may be considered as a potential adjuvant option for selected postmenopausal women, particularly when muscle loss or refractory bone pain is present, provided treatment occurs under close clinical and laboratory monitoring. Larger, contemporary randomized trials are needed to define ND's role within modern osteoporosis management.