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Scanning Skeletal Remains for Bone Mineral Density in Forensic Contexts
Published on: January 29, 2018
Bone remodeling and bone mineral density during pregnancy.
U Ulrich1, P B Miller, D R Eyre
1Department of Obstetrics and Gynecology, University of Washington, Seattle, Washington, USA. UweAUlrich@aol.com
Archives of Gynecology and Obstetrics
|September 25, 2003
Summary
Pregnancy causes significant bone loss at the lumbar spine and hip due to increased bone resorption, particularly in late pregnancy. Bone remodeling is altered, with resorption preceding formation, impacting maternal bone health.
Area of Science:
- Reproductive Endocrinology
- Skeletal Biology
- Mineral Metabolism
Background:
- Maternal skeletal changes during pregnancy are not well understood, with conflicting data on bone mineral density (BMD) changes.
- Previous studies show inconsistent results regarding bone loss or gain during gestation.
Purpose of the Study:
- To investigate the impact of pregnancy on lumbar spine, wrist, and hip bone mineral density (BMD).
- To characterize bone remodeling during pregnancy using biochemical markers of bone resorption and formation.
Main Methods:
- A longitudinal, controlled study involving 30 healthy women (15 pregnant, 15 controls).
- Bone mineral density (BMD) measured via dual-energy x-ray absorptiometry before conception and postpartum.
- Analysis of bone resorption and formation markers, and serum calcium levels throughout pregnancy.
Main Results:
- Pregnancy led to significant BMD decreases at the lumbar spine (3.4%) and trochanter (4.3%), with a slight increase at the proximal forearm.
- Bone resorption markers increased during pregnancy, peaking in the third trimester or postpartum.
- Bone formation markers showed a biphasic pattern, decreasing initially then increasing significantly in late pregnancy and postpartum.
Conclusions:
- Pregnancy is associated with high bone turnover, where resorption precedes formation, leading to uncoupled bone remodeling.
- Serum calcium levels decrease in late pregnancy as bone resorption peaks.
- Significant reductions in bone mineral density occur at trabecular bone sites like the lumbar spine and trochanter.
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