This clinical study aims to monitor and evaluate bone mineral density and fracture risk in women with singleton and twin pregnancies through the combined use of:
* two specific questionnaires developed by the Fragility Fracture Observatory (OFF), and
* a bone densitometric examination using REMS technology, performed between the 35th and 41st week of gestation.
Primary objective:
• To identify, in the third trimester of pregnancy (between the 35th and 41st gestational week), any differences in bone mineral density (BMD) between women with singleton pregnancies and women with dichorionic and monochorionic twin pregnancies.
Secondary objectives:
* Evaluate the relationship between bone mineral density (BMD) values and maternal clinical and historical parameters, such as age, body mass index (BMI), and obstetric and medical history.
* Evaluate the association between BMD values and scores obtained from validated questionnaires administered to investigate fracture risk and bone health-related quality of life in women with singleton and twin pregnancies.