Effect of number of pregnancies on bone mineral density

O Hiz1, L Ediz, I Tekeoglu

  • 1Department of Physical Therapy and Rehabilitation, Medical Faculty, Yuzuncu Yil University, Van, Turkey. ozcanhiz@gmail.com

This study investigated the effect of the number of pregnancies on bone mineral density (BMD) in 320 post-menopausal women aged between 49 and 64 years. Cases were selected from people with similar lifestyles and stratified into five groups according to the number of pregnancies. Each group was divided into two subgroups according to the duration of the menopause (3-5 years versus 6-10 years). Lumbar (L2-L4) and femoral neck BMD were measured by dual-energy X-ray absorptiometry and T-score values were used in the statistical evaluation. No significant difference was found between the number of pregnancies and BMD within each group based on the same menopause duration, but a significant correlation was found in most groups based on menopause duration: T-scores decreased as menopause duration increased. Changes in BMD are likely to be related to menopause duration, rather than the number of pregnancies.

Related Concept Videos

Bone Disorders01:29

Bone Disorders

Aging and its effect on bone remodeling is the most common cause of bone disorders. In young and healthy people, bone deposition and resorption happen at an equal rate to maintain optimal bone health.
Bone deposition is also affected by the levels of sex hormones like estrogen and testosterone that promote osteoblast activity and bone matrix synthesis. When the level of these hormones decreases due to aging, it causes a reduction in bone deposition. As a result, bone resorption by osteoclasts...
Role of Vitamins in Maintaining Bone Health01:25

Role of Vitamins in Maintaining Bone Health

The growth and maintenance of bone are regulated by a combination of nutritional factors, including vitamins, such as vitamin A, B12, C, D, and K.
Vitamin A
Vitamin A is involved in the process of bone remodeling. Retinoic acid, the active metabolite of Vitamin A, has nuclear receptors in osteoblasts and osteoclasts, which are involved in bone remodeling.
Vitamin B12
Vitamin B12 acts as a cofactor during the formation of osteoblast-related proteins, such as osteocalcin. Vitamin B12 plays a role...
Bone Remodeling01:40

Bone Remodeling

Bone remodeling is a continuous and balanced process of bone resorption by osteoclasts and bone formation by osteoblasts. In adults, it helps maintain bone mass and calcium homeostasis. While mechanical stress can stimulate turnover as part of the normal maintenance and reparative process, several hormones also regulate bone remodeling.
Hormones and Bone Tissue01:17

Hormones and Bone Tissue

The endocrine system produces and secretes hormones, which interact with the skeletal system. These hormones control bone growth, maintain bone once it is formed, and remodel it.
Hormones That Influence Osteoblasts and/or Maintain the Matrix
Several hormones are necessary for controlling bone growth and maintaining the bone matrix. The pituitary gland secretes growth hormone (GH), which, as its name implies, controls bone growth. This happens in several ways: first, it triggers chondrocyte...