Risk factors for inadequate response to ovarian stimulation in assisted reproduction cycles: systematic review

Abstract

Purpose Controlled ovarian stimulation is a fundamental part of a successful assisted reproduction treatment, and recognizing patients at risk of a poor response allows the development of targeted research to propose new treatment strategies for this specific group. The objective of this systematic review was to determine risk factors for poor ovarian response (POR) to controlled stimulation in assisted reproduction cycles described in the literature. Methods The primary databases MEDLINE, Cochrane, LILACS, and SciELO were consulted, using specific terms with a restriction for articles in English or Portuguese published in the last 10 years. Results and conclusion Our data suggest that environmental endocrine disruptors, tobacco, genetic mutations, endometriomas, ovarian surgery, chemotherapy, and short menstrual cycles are factors that influence stimulation in assisted reproduction cycles. Further studies are necessary for characterizing patients with prior risk factors.

Is the length of time between endometrial scratching and embryo transfer important for pregnancy success? An observational study

“…Our results of clinical characteristics in endometrial biopsy between the groups less than 90 days and the time between 90 and 180 days did not show differences between the groups with the characteristics of mother's age, BMI, type of endometrial preparation, natural cycle, and progesterone supplementation. Our results are not in agreement with some clinical characteristics in the literature, such as maternal age, that the older the mother, the lower the pregnancy success rate and the higher the BMI, and hence the lower the pregnancy success rate 9,14 . Another study concluded that infertility duration, endometrial thickness, and number of embryos transferred might affect the live birth rate after frozen embryo transfer among young women 15 .…”

“…Our results may enforce this idea by indicating that early embryo transfer (<90 days) is better than late embryo transfer for pregnancy success. Amaral et al 9 reviewed the influencing factors of pregnancy loss and survival probability of clinical pregnancies through ART and some factors such as maternal age, controlled ovarian hyperstimulation protocol, cycle type, and serum hCG level 14 days after transfer. Bashiri et al 10 , who reviewed on recurrent implantation failure (RIF), suggested a new initial step in approach to patients with RIF, as in this study.…”

“…Certain investigators have hypothesized that the expression of inflammatory genes after mechanical damage may be responsible for the observed increase in endometrial receptivity, which is a key factor regulating blastocyst implantation [6][7][8][9] . In fact, mechanical trauma to the endometrium alters gene expression and the local immune system (via monocyte recruitment), enhances the secretion of growth factors, and makes the endometrium more receptive to implantation 6 .…”

Genetics of female infertility: Molecular study of newborn ovary homeobox gene in poor ovarian responders

“…In general, environmental endocrine disruptors, tobacco, genetic mutations, endometriomas, ovarian surgery, chemotherapy, and short menstrual cycles are factors that affect the stimulation process in assisted reproduction cycles. [26] In this study, we excluded samples with a history of endometriomas, ovarian surgeries, and chemotherapy.…”

Análise comparativa de fatores associados à má resposta à estimulação ovariana em ciclos de fertilização in vitro

“…Na publicação original menciona-se ainda a inclusão de pacientes com fatores de risco para má-resposta além da idade como um dos critérios diagnósticos, porém não se discrimina quais. Estudo do nosso grupo demonstrou que são diversos os fatores de risco para má resposta, tais como exposição prévia à quimioterapia, ciclos menstruais curtos, mutações genéticas, tabagismo, exposição a químicos ambientais, endometriomas e cirurgias ovarianas prévias [23]. Um critério diagnóstico ideal deve ser simples, claro e reprodutível, de tal modo que a determinação de exatamente quais fatores de risco serão adotados é importante para tornar a população inclusa no critério diagnóstico mais homogênea.…”