Document Type : Original Article
Authors
1
Associate Professor, Department of Biostatistics, Health Sciences Research Center, Faculty of Health, Mashhad University of Medical Sciences, Mashhad, Iran.
2
M.Sc. Student of Biostatistics, Faculty of Health, Mashhad University of Medical Sciences, Mashhad, Iran.
3
Assistant Professor, Department of Traditional Medicine, Faculty of Traditional Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.
4
Associate Professor, Department of Obstetrics and Gynecology, Women's Health Research Center, Faculty of Medicine, University of Medical Sciences, Mashhad, Iran.
Abstract
Introduction: There are two turning points in woman life related to the menstrual cycle. One is menarche around the age of 12 and another is the cessation of menses around the age of 50. Since the age at menopause is associated with risk of several chronic diseases such as cardiovascular diseases, breast and uterine cancers and osteoporosis, identify the factors associated with early and late menopause are important.
Methods: This cross-sectional study was conducted on 2498 women aged 35 to 65 years in Mashhad city in years 2010 to 2011. Stratified - cluster sampling was done. Data gathering tool was a questionnaire whose validity was confirmed by content validity and its reliability by test-retest. Besides the age at menopause, demographic characteristics, variables related to pregnancy and socio-economic status were collected by the questionnaire. SAS software version 9.2, Kaplan-Meier and Cox Regression models were used in determining age at menopause and its effective factors. P value less than 0.05 was considered statistically significant.
Results: Mean age of women was 46.8±7.8 years. Estimated median age at menopause was 52 years by Kaplan-Meier method with confidence intervals of 95% (51.9, 52.5). 2018 women were housewife (80.8%), 539 women (21.6%) had a history of smoking and 578 cases (23.1%) had a history of hypertension. The variables of history of hypertension (p<0.001), level of education (p=0.001), and occupational status (p=0.044) significantly associated with a reduction in age at menopause, but the number of children (p<0.001) and marital status (p=0.002) has a significant relationship with increasing the age at menopause.
Conclusions: The variables related to socio-economic status such as level of education, occupational status and a history of hypertension decrease in age at menopause and number of children and marital status can increase in age at menopause.
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