Role of vitamin D and calcium in the relief of primary dysmenorrhea: a systematic review

Dysmenorrhea is one of the well-established problems among women of reproductive age and can have adverse effects on the quality of life of the individual. Some studies suggest a relationship between vitamin D (Vit D) and calcium deficiency and the emergence of early dysmenorrhea. Accordingly, a systematic study was performed to investigate the role of calcium and Vit D in the relief of primary dysmenorrhea. A systematic literature search was performed in PubMed, Web of Science, Scopus, Science Direct, and Google Scholar for papers published between 2010 and 2020. The Consolidated Standards of Reporting Trials and Strengthening the Reporting of Observational Studies in Epidemiology checklists were used to assess the quality of the studies. The risk of bias was assessed using the Cochrane risk-of-bias assessment tool. Low calcium levels lead to an increase in uterine muscle contraction and can cause pain after decreased uterine blood flow. Furthermore, low levels of Vit D can increase primary dysmenorrhea by increasing prostaglandin production or reducing intestinal calcium absorption. That being the case, Vit D and calcium intake can be effective in reducing the severity of primary dysmenorrhea and in reducing the rate of analgesic use. Low levels of Vit D and calcium are inversely related to the severity of primary dysmenorrhea, and Vit D and calcium intake can reduce the severity of primary dysmenorrhea and its associated systemic symptoms. Therefore, the use of calcium and Vit D supplements can be recommended to relieve dysmenorrhea.

[Developmental outcome of low birth-weight and preterm newborns: a review of current evidence]

Low birth weight [LEW] and preterm birth are one the most important causes of death in the world and therefore are considered as one of the major health problems. Global statistics demonstrates an increase in the prevalence of low birth weight in the developing countries. Low birth weight infants are exposed to complications such as major neurosensory impairements, cerebral palsy, cognitive and language delays, neuromotor developmental delay, blindness and hearing loss, behavioral and psychosocial disorders, learning difficulties and dysfunction in scholastic performances. The majority of infant's death and developmental disorders were due to disorders relating to prematurity and unspecified low birth weight. Infants weighing less than 2500 g, is a major determinant of both neonatal and infant mortality rates and, together with congenital anomalies [e.g., cardiac, central nervous system, and respiratory], contributes significantly to childhood morbidity. Various studies indicate that low birth weight infants are suffering from physiological and psychosocial disabilities, two to three times more than the other children. At school age, preterm and low birth weight infants have poorer physical growth, cognitive function, and school performance. These disadvantages appear to persist into adulthood and therefore have broad implications for society. Although the survival rates have increased dramatically and the incidence of morbidities has decreased, the complications are still considered to be associated with economical and social burdens. Most children with Low birth weight suffer from multiple disabilities. Therefore, they need special and consistent care. On demand of reducing the infant mortality rate, the need to decrease the complications in low birth weight and preterm infants should be considered by the policy makers in health care system. In this review article, we assessed current evidences on developmental outcomes of low birth weight and preterm newborns