RESUMEN
Abstract Background: Melatonin is a hormone produced by the pineal gland and it has antioxidant properties. Aim: This study aimed to evaluate the effects of melatonin on assisted reproductive technologies through a systematic review and a meta-analysis. Materials and methods: Search strategies were used in PubMed and in other databases covering the last 15 years. After screening for eligibility, 17 articles were selected for the systematic review. For the meta-analysis statistics, two groups were formed, the treatment group (with melatonin) and the control group (without melatonin) for various assisted reproduction outcomes. Results: The main results were that no statistical differences were found concerning the clinical pregnancy outcome (p = 0.64), but there was a statistical difference with respect to Mature Oocytes (MII) (p = 0.001), antral follicle count (p = 0.0002), and the fertilization rate (p ≤ 0.0001). Conclusions: Melatonin had beneficial effects such as the improvement in the fertilization rate, although the authors did not obtain significance in the clinical pregnancy rate.
RESUMEN
A má resposta ovariana em fertilização in vitro apresenta uma prevalência de 2 a 30% dos ciclos de estimulação ovariana. Diversos tratamentos adjuvantes são encontrados na literatura, no entanto, a utilização de hormônio de crescimento (GH) adjuvante foi o que apresentou os resultados mais promissores, com elevação da taxa de gravidez em até 17% nestas pacientes. O objetivo deste estudo foi realizar uma revisão da literatura para esclarecer como o GH atua na estimulação ovariana e para investigar as formas de utilização em más respondedoras. Foram encontrados estudos que relacionam a utilização de GH com o aumento no número de oócitos, na sua qualidade, na redução do tempo de êxito na concepção, na taxa de nascimentos, no estímulo de secreção de progesterona e de gonadotrofina coriônica humana (hCG). Foram discutidas as limitações dos estudos anteriores e de que forma limitam ou condicionam os resultados encontrados. Apesar dos estudos revisados terem diferido na dosagem e na forma de utilização do GH, seus resultados suportaram a proposta de utilização de GH no protocolo de estimulação de pacientes más respondedoras.(AU)
Between 2 and 30% of the patients submitted to ovarian stimulation present poor ovarian response. Several adjuvant treatments were found in the literature, however, the use of growth hormone (GH) as adjuvant presented the most promising results, increasing pregnancy rates in up to 17% in these patients. The objective of this study was to review the literature in order to clarify how GH acts on ovarian stimulation and to investigate ways to use it in poor responders. Studies that relate the use of GH with increase in the number of oocytes, on its quality, in the reduction of time to conception, life birth rate, in the stimulus of progesterone and human corionic gonadotropin (hCG) secretion were found.. The limitations found on previous studies and the way in which they limit or condition the founded results were discussed. Although the dosage and ways of use of GH have differed on the reviewed studies, their results supported the proposal of GH use on the stimulation protocols for poor responder patients.(AU)