Reply: GnRH antagonists vs. long GnRH agonists in IVF: significant flaws in a meta-analysis lead to invalid conclusions
(Source: Human Reproduction Update)
Source: Human Reproduction Update - December 29, 2017 Category: OBGYN Source Type: research
GnRH antagonists vs. long GnRH agonists in IVF: significant flaws in a meta-analysis lead to invalid conclusions
(Source: Human Reproduction Update)
Source: Human Reproduction Update - December 29, 2017 Category: OBGYN Source Type: research
Combined oral contraceptives and/or antiandrogens versus insulin sensitizers for polycystic ovary syndrome: a systematic review and meta-analysis
AbstractBACKGROUNDAndrogen excess is a key pathogenetic mechanism in polycystic ovary syndrome (PCOS), although hyperinsulinism also contributes to androgen secretion. Therapeutic approaches for adult patients not seeking fertility include combined oral contraceptives (COC), antiandrogens (AA) and/or insulin sensitizers, although these practices are supported by limited high-quality evidence.OBJECTIVE AND RATIONALEWe aimed to assess the efficacy and safety of these common treatments for PCOS by conducting a meta-analysis of RCTs with the following review questions: Which is the more appropriate therapeutic approach for hyp...
Source: Human Reproduction Update - December 27, 2017 Category: OBGYN Source Type: research
Testicular organoids: a new model to study the testicular microenvironment in vitro?
AbstractBACKGROUNDIn recent decades, a broad range of strategies have been applied to model the testicular microenvironmentin vitro. These models have been utilized to study testicular physiology and development. However, a system that allows investigations into testicular organogenesis and its impact in the spermatogonial stem-cell (SSC) nichein vitro has not been developed yet. Recently, the creation of tissue-specific organ-like structures called organoids has resurged, helping researchers to answer scientific questions that previousin vitro models could not help to elucidate. So far, a small number of publications have...
Source: Human Reproduction Update - December 21, 2017 Category: OBGYN Source Type: research
Regulation of chromosome segregation in oocytes and the cellular basis for female meiotic errors
AbstractBACKGROUNDMeiotic chromosome segregation in human oocytes is notoriously error-prone, especially with ageing. Such errors markedly reduce the reproductive chances of increasing numbers of women embarking on pregnancy later in life. However, understanding the basis for these errors is hampered by limited access to human oocytes.OBJECTIVE AND RATIONALEImportant new discoveries have arisen from molecular analyses of human female recombination and aneuploidy along with high-resolution analyses of human oocyte maturation and mouse models. Here, we review these findings to provide a contemporary picture of the key player...
Source: Human Reproduction Update - December 13, 2017 Category: OBGYN Source Type: research
The associations of thiopurines with male fertility and paternally exposed offspring: a systematic review and meta-analysis
AbstractBACKGROUNDThiopurines are widely used immunosuppressive agents. In high dosages, they inhibit the purine synthesis and are considered to be possibly harmful to spermatogenesis, and subsequently to men ’s fertility and their offspring. However, the clear association between thiopurine exposure and male fertility and reproduction safety, if any, is still poorly understood.OBJECTIVE AND RATIONALEThe aim of this review was to systematically summarize and meta-analyse the available data, derived from animal and human studies, regarding the influence of thiopurine exposure on fertility and conception safety in men and ...
Source: Human Reproduction Update - November 28, 2017 Category: OBGYN Source Type: research
Extracellular matrix in uterine leiomyoma pathogenesis: a potential target for future therapeutics
AbstractBACKGROUNDUterine leiomyoma (also known as fibroid or myoma) is the most common benign tumor of the uterus found in women of reproductive age. It is not usually fatal but can produce serious clinical symptoms, including excessive uterine bleeding, pelvic pain or pressure, infertility and pregnancy complications. Due to lack of effective medical treatments surgery has been a definitive choice for the management of this tumor.OBJECTIVE AND RATIONALEExtracellular matrix (ECM) accumulation and remodeling are thought to be crucial for fibrotic diseases such as uterine leiomyoma. Indeed, ECM plays important role in formi...
Source: Human Reproduction Update - November 23, 2017 Category: OBGYN Source Type: research
Is frozen embryo transfer better for mothers and babies? Can cumulative meta-analysis provide a definitive answer?
AbstractBACKGROUNDInitial observational studies and a systematic review published 5 years ago have suggested that obstetric and perinatal outcomes are better in offspring conceived following frozen rather than fresh embryo transfers, with reduced risks of preterm birth, small for gestational age, low birth weight and pre-eclampsia. More recent primary studies are beginning to challenge some of these findings. We therefore conducted an updated systematic review and cumulative meta-analysis to examine if these results have remained consistent over time.OBJECTIVE AND RATIONALEThe aim of this study was to perform a systematic ...
Source: Human Reproduction Update - November 13, 2017 Category: OBGYN Source Type: research
Diabetes-induced hyperglycemia impairs male reproductive function: a systematic review
AbstractBACKGROUNDHyperglycemia can result from a loss of pancreatic beta-cells or a decline in their function leading to decreased insulin secretion or may arise from insulin resistance and variable degrees of inadequate insulin secretion resulting in diabetes and related comorbidities. To date several reviews have addressed the issue of diabetes-related male infertility but most have focused on how metabolic syndrome causes the decline in male fertility. However, a comprehensive overview as to how diabetes-induced hyperglycemia impairs male fertility is missing. Impaired regulation of glucose and the resultant hyperglyce...
Source: Human Reproduction Update - November 10, 2017 Category: OBGYN Source Type: research
In vivo oxygen, temperature and pH dynamics in the female reproductive tract and their importance in human conception: a systematic review
AbstractBACKGROUNDDespite advances in ART, implantation and pregnancy rates per embryo transfer still remain low. IVF laboratories strive to ensure that the process of handling gametesin vitro closely mimics thein vivo environment. However, there remains a lack of knowledge regarding thein vivo regulation and dynamic variation in biophysical parameters such as oxygen concentration, pH and temperature within the reproductive tract.OBJECTIVE AND RATIONALETo undertake a systematic review of the current understanding of the physico-chemical parameters of oxygen tension (pO2), pH and temperature within the female reproductive t...
Source: Human Reproduction Update - October 25, 2017 Category: OBGYN Source Type: research
Patient-centered early pregnancy care: a systematic review of quantitative and qualitative studies on the perspectives of women and their partners
AbstractBACKGROUNDEarly pregnancy complications, defined as miscarriage, recurrent miscarriage or ectopic pregnancy, affect the physical and psychological well-being of intended parents. Research in this field so far has focused mainly on improving accuracy of diagnostic tests and safety and effectiveness of therapeutic management. An overview of aspects of care valued by women and/or their partners is missing.OBJECTIVE AND RATIONALEThis systematic review aims to provide an overview of aspects of care valued by women and/or their partners faced with early pregnancy complications and to identify potential targets for improv...
Source: Human Reproduction Update - October 11, 2017 Category: OBGYN Source Type: research
The epidermal growth factor network: role in oocyte growth, maturation and developmental competence
AbstractBACKGROUNDThe LH surge induces great physiological changes within the preovulatory follicle, which culminate in the ovulation of a mature oocyte that is capable of supporting embryo and foetal development. However, unlike mural granulosa cells, the oocyte and its surrounding cumulus cells are not directly responsive to LH, indicating that the LH signal is mediated by secondary factors produced by the granulosa cells. The mechanisms by which the oocyte senses the ovulatory LH signal and hence prepares for ovulation has been a subject of considerable controversy for the past four decades. Within the last 15 years sev...
Source: Human Reproduction Update - September 20, 2017 Category: OBGYN Source Type: research
How effective are weight-loss interventions for improving fertility in women and men who are overweight or obese? A systematic review and meta-analysis of the evidence
AbstractBACKGROUNDThe prevalence of obesity is increasing worldwide, with a corresponding increase in overweight and obese patients referred with infertility. This systematic review aimed to determine whether non-surgical weight reduction strategies result in an improvement in reproductive parameters affected by obesity, e.g. delayed time to pregnancy, oligozoospermia and azoospermia. No prior reviews have examined this within the general fertility population, or in both sexes.OBJECTIVE AND RATIONALEOur objective was to answer the question: ‘In overweight and obese women, men and couples seeking fertility treatment, what...
Source: Human Reproduction Update - September 13, 2017 Category: OBGYN Source Type: research
Disentangling puberty: novel neuroendocrine pathways and mechanisms for the control of mammalian puberty
AbstractBACKGROUNDPuberty is a complex developmental event, controlled by sophisticated regulatory networks that integrate peripheral and internal cues and impinge at the brain centers driving the reproductive axis. The tempo of puberty is genetically determined but is also sensitive to numerous modifiers, from metabolic and sex steroid signals to environmental factors. Recent epidemiological evidence suggests that the onset of puberty is advancing in humans, through as yet unknown mechanisms. In fact, while much knowledge has been gleaned recently on the mechanisms responsible for the control of mammalian puberty, fundame...
Source: Human Reproduction Update - August 30, 2017 Category: OBGYN Source Type: research
