title: Bone metabolic changes during pregnancy: a period of vulnerability to osteoporosis and fracture.
abstract: Changes in bone density and bone markers suggest that pregnancy is associated with deterioration of bone mass in the mother. The metabolism of calcium resets to allow for the needs imposed by the building of the fetal skeleton. The fetus contributes to the process through the output of regulators from the placenta. Understanding of the whole process is limited, but some changes are unambiguous. There is an increase in the circulating levels of vitamin D, but its functional impact is unclear. Fetal parathyroid hormone (PTH) and PTH-related peptide (PTHrp) play an indirect role through support of a calcium gradient that creates hypercalcemia in the fetus. Placental GH, which increases up to the end of pregnancy, may exert some anabolic effects, either directly or through the regulation of the IGF1 production. Other key regulators of bone metabolism, such as estrogens or prolactin, are elevated during pregnancy, but their role is uncertain. An increase in the ratio of receptor activator of nuclear factor kappa B ligand (RANKL) to osteoprotegerin (OPG) acts as an additional pro-resorbing factor in bone. The increase in bone resorption may lead to osteoporosis and fragility fracture, which have been diagnosed, although rarely. However, the condition is transitory as long-term studies do not link the number of pregnancies with osteoporosis. Prevention is limited by the lack of identifiable risk factors. When fractures are diagnosed, rest, analgesics, or, when indicated, orthopedic intervention have demonstrated efficacy. Systemic treatment with anti-osteoporotic drugs is effective, but the potential harm to the fetus imposes caution in their use.
authors.affiliation: Fundación para la Investigación Sanitaria y Biomédica (FISABIO)Juan de Garay 21, 46017 Valencia, SpainDepartment of GeneticsUniversity of Valencia and Research Foundation, INCLIVA, Avenida Blasco Ibáñez 15, 46010 Valencia, SpainDepartment of Functional Biology and Physical AnthropologySchool of Biological Sciences, University of Valencia, Burjasot Campus, Valencia, SpainDepartment of PediatricsObstetrics and Gynecology, Facultad de Medicina, University Hospital Dr Peset, University of Valencia, Avenida Blasco Ibáñez 15, 46010 Valencia, Spain.
authors.forename: Lucía
authors.initials: L
authors.lastname: Sanz-Salvador
authors.affiliation: Fundación para la Investigación Sanitaria y Biomédica (FISABIO)Juan de Garay 21, 46017 Valencia, SpainDepartment of GeneticsUniversity of Valencia and Research Foundation, INCLIVA, Avenida Blasco Ibáñez 15, 46010 Valencia, SpainDepartment of Functional Biology and Physical AnthropologySchool of Biological Sciences, University of Valencia, Burjasot Campus, Valencia, SpainDepartment of PediatricsObstetrics and Gynecology, Facultad de Medicina, University Hospital Dr Peset, University of Valencia, Avenida Blasco Ibáñez 15, 46010 Valencia, Spain.
authors.forename: Miguel Ángel
authors.initials: MÁ
authors.lastname: García-Pérez
authors.affiliation: Fundación para la Investigación Sanitaria y Biomédica (FISABIO)Juan de Garay 21, 46017 Valencia, SpainDepartment of GeneticsUniversity of Valencia and Research Foundation, INCLIVA, Avenida Blasco Ibáñez 15, 46010 Valencia, SpainDepartment of Functional Biology and Physical AnthropologySchool of Biological Sciences, University of Valencia, Burjasot Campus, Valencia, SpainDepartment of PediatricsObstetrics and Gynecology, Facultad de Medicina, University Hospital Dr Peset, University of Valencia, Avenida Blasco Ibáñez 15, 46010 Valencia, Spain.
authors.forename: Juan J
authors.initials: JJ
authors.lastname: Tarín
authors.affiliation: Fundación para la Investigación Sanitaria y Biomédica (FISABIO)Juan de Garay 21, 46017 Valencia, SpainDepartment of GeneticsUniversity of Valencia and Research Foundation, INCLIVA, Avenida Blasco Ibáñez 15, 46010 Valencia, SpainDepartment of Functional Biology and Physical AnthropologySchool of Biological Sciences, University of Valencia, Burjasot Campus, Valencia, SpainDepartment of PediatricsObstetrics and Gynecology, Facultad de Medicina, University Hospital Dr Peset, University of Valencia, Avenida Blasco Ibáñez 15, 46010 Valencia, Spain antonio.cano@uv.es.
authors.forename: Antonio
authors.initials: A
authors.lastname: Cano
mesh_terms: D000818:Animals; D015519:Bone Density / Q000502:physiology*; D001862:Bone Resorption / Q000175:diagnosis / Q000453:epidemiology / Q000378:metabolism; D005260:Female; D050723:Fractures, Bone / Q000175:diagnosis / Q000453:epidemiology / Q000378:metabolism*; D006801:Humans; D010024:Osteoporosis / Q000175:diagnosis / Q000453:epidemiology / Q000378:metabolism*; D010281:Parathyroid Hormone / Q000378:metabolism; D044162:Parathyroid Hormone-Related Protein / Q000378:metabolism; D011247:Pregnancy; D011248:Pregnancy Complications / Q000175:diagnosis / Q000378:metabolism*; D014807:Vitamin D / Q000378:metabolism
chemical_list: D010281:Parathyroid Hormone; D044162:Parathyroid Hormone-Related Protein; D014807:Vitamin D