IntrOductIOnToday, research on women's health has greatly improved [1,2]. PMS is a common health problem in women in reproductive age and defined as a collection of emotional symptoms, with or without physical symptoms, related to a woman's menstruation cycle [3]. PMS is occur during the luteal phase of menses, however, it disappear with menstrual flow. The prevalence of PMS has been reported in 20 to 32 % of premenopausal [4] and 30-40% of the reproductive female population [5].There are several different symptoms have been associated with PMS [6]. The symptoms are cyclic and recurrent. The symptoms can change in extent and strength during different cycles [7]. Different etiologies have been suggested for the PMS. The abnormal function of hypothalamic-pituitary-adrenal axis (HPA), which leads to defect in adrenal hormone secretion, nutritional defects and environmental factors are the main factors for PMS [8]. The endocrine systems is one of the theories for explaining the physiopathological mechanism of PMS [7].PMS affects women's quality of life, economic and social performance. In other study, about 23-31 % of reproductive aged women experience PMS to a degree that affects their daily lives [9].PMS can cause mood disorders and its complications [10]. Therefore, during the last 2 decades; several studies have been conducted on various treatment options regarding PMS [11][12][13][14].Due to side effects of PMS, the present study aimed to investigate the prevalence of PMS using meta-analysis method.
MethOds search strategyThis originally meta-analysis reviewed the world wide prevalence of PMS. We electronically searched the English-language medical literature published between 1996 -2011 using the available databases including Pub Med and Medline. The protocol was obstetrics and gynaecology section designed using widely recommended methods and reported according to PRISMA [15]. Using the medical subject headings (MeSH), we searched "Premenstrual Syndrome", "Epidemiology of PMS" and "prevalence of Premenstrual Syndrome" including all subheadings.
study selection and data extractionTwo researchers independently screened the titles of all recode citations, removing duplicate records and distinguishing potentially relevant studies for inclusion. Abstracts from selected citations were then independently reviewed by two researchers for further relevance, with full text manuscripts retrieved as appropriate. In the disagreement cases, a third consultant acted as an intervener. This search selected 53 abstracts. The following data was extracted from included studies: first author, study population, type of data collection, sampling methods, type of study and main findings. The eligible studies were those which reported the "Premenstrual Syndrome" and "prevalence of Premenstrual Syndrome". However, studies which included treatment of PMS were excluded. Out of 53 abstracts, 26 papers were categorized as potentially eligible for meta-analysis and systematic review. In the last stage 17 full text articles were used in the ...