Human pineal physiology and functional significance of melatonin

Current treatments of subfertile couples are usually empiric, as the true cause of subfertility often remains unknown. Therefore, we outline the role of nutritional and biochemical factors in reproduction and subfertility. A literature search was performed using MEDLINE, Science Direct and bibliographies of published work with both positive and negative results. The studies showed that folate has a role in spermatogenesis. In female reproduction, folate is also important for oocyte quality and maturation, implantation, placentation, fetal growth and organ development. Zinc has also been implicated in testicular development, sperm maturation and testosterone synthesis. In females, zinc plays a role in sexual development, ovulation and the menstrual cycle. Both folate and zinc have antioxidant properties that counteract reactive oxygen species (ROS). Thiols, such as glutathione, balance the levels of ROS produced by spermatozoa and influence DNA compaction and the stability and motility of spermatozoa. Oocyte maturation, ovulation, luteolysis and follicle atresia are also affected by ROS. After fertilization, glutathione is important for sperm nucleus decondensation and pronucleus formation. Folate, zinc, ROS and thiols affect apoptosis, which is important for sperm release, regulation of follicle atresia, degeneration of the corpus luteum and endometrial shedding. Therefore, the concentrations of these nutrients may have substantial effects on reproduction. In conclusion, nutritional and biochemical factors affect biological processes in male and female reproduction. Further research should identify pathways that may lead to improvements in care and treatment of subfertility.

The importance of folate, zinc and antioxidants in the pathogenesis and prevention of subfertility

Background The main objective of individualization of treatment in IVF is to offer every single woman the best treatment tailored to her own unique characteristics, thus maximizing the chances of pregnancy and eliminating the iatrogenic and avoidable risks resulting from ovarian stimulation. Personalization of treatment in IVF should be based on the prediction of ovarian response for every individual. The starting point is to identify if a woman is likely to have a normal, poor or a hyper response and choose the ideal treatment protocol tailored to this prediction. The objective of this review is to summarize the predictive ability of ovarian reserve markers, such as antral follicle count (AFC) and anti-Mullerian hormone (AMH), and the therapeutic strategies that have been proposed in IVF after this prediction. Methods A systematic review of the existing literature was performed by searching Medline, EMBASE, Cochrane library and Web of Science for publications in the English language related to AFC, AMH and their incorporation into controlled ovarian stimulation (COS) protocols in IVF. Literature available to May 2013 was included. Results The search generated 305 citations of which 41 and 25 studies, respectively, reporting the ability of AMH and AFC to predict response to COS were included in this review. The literature review demonstrated that AFC and AMH, the most sensitive markers of ovarian reserve identified to date, are ideal in planning personalized COS protocols. These sensitive markers permit prediction of the whole spectrum of ovarian response with reliable accuracy and clinicians may use either of the two markers as they can be considered interchangeable. Following the categorization of expected ovarian response to stimulation clinicians can adopt tailored therapeutic strategies for each patient. Current scientific trend suggests the elective use of the GnRH antagonist based regimen for hyper-responders, and probably also poor responders, as likely to be beneficial. The selection of the appropriate and individualized gonadotrophin dose is also of paramount importance for effective COS and subsequent IVF outcomes. Conclusion Personalized IVF offers several benefits; it enables clinicians to give women more accurate information on their prognosis thus facilitating counselling especially in cases of extremes of ovarian response. The deployment of therapeutic strategies based on selective use of GnRH analogues and the fine tuning of the gonadotrophin dose on the basis of potential ovarian response in every single woman can allow for a safer and more effective IVF practice.

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Individualization of controlled ovarian stimulation in IVF using ovarian reserve markers: from theory to practice

Melatonin receptors in humans: biological role and clinical relevance.

DNA fragmentation is an important factor in the aetiology of male infertility. However, it is still underevaluated and its inclusion in routine semen analysis is debated. DNA fragmentation has been shown to be a robust indicator of fertility potential, more so than conventional semen parameters. Men with high DNA fragmentation levels have significantly lower odds of conceiving, naturally or through procedures such as intrauterine insemination and IVF. Couples may be counselled to proceed directly to intracytoplasmic sperm injection as it is more successful in this group, avoiding costly procedures, recurrent failures or pregnancy losses; however, this treatment is not without limitations or risks. Ideally DNA fragmentation should be minimized where possible. Oxidative stress is the major cause of DNA fragmentation in spermatozoa. Endogenous and exogenous factors that contribute to oxidative stress are discussed, and in many cases are shown to be easily modifiable. Antioxidants play a protective role, although a delicate balance of reduction and oxidation is required for essential functions, including fertilization. Reducing oxidative stress may improve a couple's chances of conception either naturally or via assisted reproduction. Sources of oxidative stress therefore should be thoroughly examined in men with high levels of DNA fragmentation and modified where possible. DNA fragmentation is an important factor in the aetiology of male infertility. However it is still underevaluated and its inclusion in routine semen analysis is still debated. DNA fragmentation has been shown to be a robust indicator of fertility potential, more so than conventional semen parameters. Men with high levels of DNA fragmentation will have significantly lower odds of conceiving naturally or through procedures such as intrauterine insemination and IVF. Intracytoplasmic sperm injection (ICSI) may be much more successful in this group, and couples may be counselled to proceed directly to ICSI, avoiding costly procedures, recurrent failures or pregnancy losses. However, ICSI is not without its limitations or risks. Ideally, DNA fragmentation should be investigated and minimized where possible in men trying to conceive naturally or through assisted reproduction technology. Oxidative stress is the major cause of DNA fragmentation in spermatozoa. Endogenous and exogenous factors that contribute to oxidative stress are discussed and in many cases are easily modifiable. Antioxidants play a protective role, although a delicate balance of reduction and oxidation is required for essential sperm function, including fertilization. Reducing oxidative stress may improve a couple's chances of conception either naturally or via assisted reproduction treatment. Sources of oxidative stress therefore should be thoroughly examined in men with high levels of DNA fragmentation and modified where possible.

https://www.rbmojournal.com/article/S1472-6483(14)00118-7/pdf

Sperm DNA damage caused by oxidative stress: modifiable clinical, lifestyle and nutritional factors in male infertility.

Objective
To evaluate predictive role of day–3 serum anti-Mullerian hormone (AMH) levels and antral follicle count (AFC) in ovarian hyperstimulation syndrome (OHSS) in patients undergoing IVF/ICSI cycles.

Serum anti-Müllerian hormone and antral follicle count as predictive markers of OHSS in ART cycles.

Does leukocytospermia associate with poor semen parameters and sperm functions in male infertility? The role of different seminal leukocyte concentrations.

Objective
To evaluate the association between different basal serum levels of anti-Mullerian hormone (AMH) and oocyte-embryo quality and IVF outcomes.

Different serum anti-Müllerian hormone concentrations are associated with oocyte quality, embryo development parameters and IVF-ICSI outcomes

Sperm counts in Asian men: Reviewing the trend of past 50 years

Purpose
To investigate the association between follicular fluid homocysteine levels and embryo quality and pregnancy rates in patients undergoing assisted reproduction.

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Tulay Irez

Papers

Serum anti-Müllerian hormone and antral follicle count as predictive markers of OHSS in ART cycles.

Does leukocytospermia associate with poor semen parameters and sperm functions in male infertility? The role of different seminal leukocyte concentrations.

Different serum anti-Müllerian hormone concentrations are associated with oocyte quality, embryo development parameters and IVF-ICSI outcomes

Sperm counts in Asian men: Reviewing the trend of past 50 years

The association between homocysteine in the follicular fluid with embryo quality and pregnancy rate in assisted reproductive techniques