Elsevier

Maturitas

Volume 57, Issue 4, 20 August 2007, Pages 392-398
Maturitas

Influence of parity on bone mineral density and peripheral fracture risk in Moroccan postmenopausal women

https://doi.org/10.1016/j.maturitas.2007.04.006Get rights and content

Abstract

The aims of the study were to determine: (1) the relationship between parity and bone mineral density (BMD); (2) the relationship between parity and osteoporotic peripheral fractures.

Material and methods

The group studied included 730 postmenopausal women. Patients were separated into four groups according to the number of fullterm pregnancies, group 1: nulliparae, group 2: one to three pregnancies, group 3: four to five pregnancies, and group 4: six and more pregnancies. Additionally, patients were separated into three groups according to their ages, as <50 years, 50–59 years and ≥60 years.

Results

The median parity was 4 [0–20]. All the patients with parity greater than six had spine and hip BMD values significantly lower than values in the other groups (p < 0.001). After adjustment for age and body mass index (BMI), decreased lumbar and total hip BMD were still associated to increased parity (analysis of covariance (ANCOVA), p = 0.04 and 0.023, respectively). The relation between parity and lumbar BMD was highly significant among women aged <50 years (age-adjusted p = 0.022), while there was no parity-spine BMD association in the other age groups. The relation between parity and hip BMD was seen only in the group 50–59 years (age-adjusted p = 0.042). A positive history for peripheral fractures was present in 170 (23%) patients. There was relationship between parity and peripheral fractures neither in the whole population nor in the sub-groups according to age.

Discussion

The present study suggests that the BMD of the spine and hip decreases with an increasing number of pregnancies, and this situation shows variations in different age groups. However, there was no correlation between parity level and peripheral fractures.

Section snippets

Design and setting

It was a cross-sectional study. The group studied included 730 postmenopausal women. They had been selected consecutively from a group of postmenopausal women referred to the outpatient Bone Densitometry Center (El Ayachi University-Hospital, Sale, Morocco). All subjects were referred to this centre for osteoporosis risk factors, including menopause.

A study inclusion criteria was: postmenopausal status (at least 1 year of menopause). Exclusion criteria consisted in having a history of: (1)

Results

Clinical characteristics of the 730 women included in the analysis are shown in Table 1 according to parity. The number of children ranged from 0 to 20 with a median parity of four live births. The mean age of women was 59.4 (±7.6) years and was significantly correlated with parity level. Increasing parity was associated with higher years since menopause (p < 0.001), higher BMI (p = 0.001) and higher percentage of wearing weil (p < 0.001). In contrast, increasing parity was not significantly

Discussion

In the present study, an inverse relationship between parity and BMD was observed. The BMD values decreased as the number of pregnancies increased. Among our patients, women with six and more pregnancies were seen to have significantly lower BMD values for both lumbar vertebra and hip versus other groups. This relationship remained significant after adjusting for age, and BMI.

Interestingly, the BMD decreased with each delivery in all skeletal areas scanned but was more consistent in spine. Our

Acknowledgement

This study has been supported by the University Mohammed V Souissi, Rabat, Morocco.

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