Reproduction and Fertility cover

 

 

The role that lifestyle factors play in fertility issues has generated some amount of interest and questions among stakeholders. This review aims to highlight the impact of lifestyle behaviors on the fertility potential of an individual and what can be done to prevent or improve reproductive outcomes. Relevant published articles on the effect of lifestyle behaviors were obtained from Medline, Pubmed and Google scholar search engines for the study. The review of the literature indicates a negative impact of modifiable lifestyle factors such as fat-rich diets, delayed childbearing/age of starting family, smoking, alcohol misuse, sexual behavior, anxiety/depression and perception/beliefs were associated with fertility. The ensuing stress precipitates social behaviors such as excessive alcohol and caffeine consumption, tobacco smoking, misuse of recreational drugs/medications, which increases the risk of sexually transmitted diseases and infection leading to infertility. Practical recommendations to modify lifestyle behaviors and the impact of misconception of Assisted Reproductive Technology in the treatment of infertility are discussed. The need to make appropriate behavioral changes to stem the tide of infertility in Nigeria is imperative. More reproductive health education is needed to create the necessary awareness of the etiologies of infertility and the importance of in vitro fertilization treatment as a means of conceiving ‘natural’ babies is suggested.

Lay summary

Scientific evidence has suggested that modifiable lifestyle factors (consumption fat-rich diets, delayed childbearing/age of starting family, smoking, alcohol misuse, sexual behavior, anxiety/depression and perception/beliefs) play important roles in the general health and wellbeing of individuals including fertility. Evidence exists of an association between lifestyle behaviors and infertility in both men and women. Understanding the various processes through which modifiable lifestyle behaviors impair fertility will help to assist in the management of affected individuals. We conducted a comprehensive review of published studies to assess how lifestyle factors inhibit fertility and practical ways to ameliorate them. This review also deals with the misconception of Assisted Reproductive Technology in the treatment of infertility. The need to make appropriate behavioral changes to stem the tide of infertility in Nigeria is imperative. More reproductive health education is needed to create the necessary awareness of the causes of infertility and the importance of in vitro fertilization in the treatment of infertility.

Altered gut microbiota (dysbiosis), inflammation and weight gain are pivotal to the success of normal pregnancy. These are features of metabolic syndrome that ordinarily increase the risk of type 2 diabetes in non-pregnant individuals. Though gut microbiota influences host energy metabolism and homeostasis, the outcome (healthy or unhealthy) varies depending on pregnancy status. In a healthy pregnancy, the gut microbiota is altered to promote metabolic and immunological changes beneficial to the mother and foetus but could connote a disease state in non-pregnant individuals. During the later stages of gestation, metabolic syndrome-like features, that is, obesity-related gut dysbiotic microbiota, increased insulin resistance, and elevated pro-inflammatory cytokines, promote energy storage in adipose tissue for rapid foetal growth and development, and in preparation for energy-consuming processes such as parturition and lactation. The origin of this gestation-associated host–microbial interaction is still elusive. Therefore, this review critically examined the host–microbial interactions in the gastrointestinal tract of pregnant women at late gestation (third trimester) that shift host metabolism in favour of a diabetogenic or metabolic syndrome-like phenotype. Whether the diabetogenic effects of such interactions are indeed beneficial to both mother and foetus was also discussed with plausible mechanistic pathways and associations highlighted.

Lay summary

In non-pregnant women, increased blood glucose, fat accumulation, and prolonged immune response lead to obesity and diabetes. However, during the later stages of pregnancy, the changes in the body’s metabolism described previously do not lead to disease, instead pregnancy facilitates the storage of sufficient energy in fat cells for rapid growth and development of the foetus. The excess energy stores also prepares the mother for labour and breastfeeding. This review examines the role of the normal bacteria in the digestive tract in this beneficial energy accumulation and transfer between the mother and foetus without leading to obesity, diabetes and hypertension in pregnancy.

The first attempts at generating functional human oocytes by using the transfer of patients’ somatic cell nuclei, as DNA source, into donor enucleated oocytes date back to the early 2000s. After initial attempts, that gave rather encouraging results, the technique was abandoned because of adverse results with this technique in the mouse model. Priority was then given to the use of induced pluripotent stem (iPS) cells, based on excellent results in the mouse, where mature oocytes and live healthy offspring were achieved. However, these results could not be reproduced in humans, and oogenesis with human iPS cells did not continue beyond the stage of oogonium. These data suggest that the use of enucleated donor oocytes will be necessary to achieve fertilizable human oocytes with somatic cell-derived DNA. The main problem of all these techniques is that they have to meet with two, sometimes contradictory, requirements: the haploidization of somatic cell-derived DNA, on the one hand, and the remodeling/reprogramming of DNA of somatic cell origin, so as to be capable of supporting all stages of preimplantation and postimplantation development and to give rise to all cell types of the future organism. Further research is needed to determine the optimal strategy to cope with these two requirements.

Lay summary

The recourse to artificial oocytes, generated by using the patient’s own DNA derived from cells of somatic origin, represents the ultimate opportunity for women who lack healthy oocytes of their own but yearn for genetically related offspring. Many different pathologies, such as ovarian cancer, premature ovarian failure, other ovarian diseases and natural, age-related ovarian decay can cause the absence of available oocytes. The demand for artificial oocytes is increasing continuously, mainly because of the tendency to postpone maternity to still more advanced ages, when the quantity and quality of oocytes is low. This minireview focuses on the generation of artificial oocytes using different strategies and scenarios, based on the accumulated experience in humans and experimental animals.

Periodontal health is today conceived as an integral part of systemic health itself and no longer as a single factor. Literature recognizes that the presence of periodontal disease can represent a risk factor for numerous systemic conditions such as heart disease and diabetes. In recent years we have witnessed a progressive interest regarding the influence exerted by this condition on the reproductive sphere, as well as on the possible repercussions on the conception possibilities. Following the analysis of the limited number of studies available for the correlation between periodontal disease and female infertility, it could be inferred that this condition can be equated to the presence of a real outbreak of infection and therefore exert its influence not only through bacterial translocation in the bloodstream, causing the systemic dissemination of pathogens, but also through the production of cytokines and immunoglobulins by inflammatory mediators. This situation limits bacteria growth, but it could cause damage to the fetus, to the reproductive system, and could invalidate conception attempts. Although many other studies and research are needed to better clarify the mechanism underlying the possible correlation between periodontal disease and female infertility, this article aims to review all the available literature concerning this topic.

October 22, 2020

New Editorial Board members

 

Reproduction and Fertility has two new members who have joined the Editorial Board, Dr Channa Jayasena and Dr Mehdi Ommati.

 

May 7, 2020

Reproduction and Fertility – now open for submissions

 

In partnership with Bioscientifica, the Society for Reproduction and Fertility is pleased to announce the launch of their new fully open-access, peer-reviewed journal, Reproduction and Fertility.

Led by Co-Editors-in-Chief Andrew Horne and Norah Spears, Reproduction and Fertility will see vigorous yet rapid peer review of the latest basic, translational and clinical research in the field.

 

May 7, 2020

Article Publication Charge waived

 

In celebration of the launch of Reproduction and Fertility, Bioscientifica and the Society for Reproduction and Fertility are sponsoring the Article Publication Charge during the launch years of the journal*.

*The Society for Reproduction and Fertility and Bioscientifica reserve the right to withdraw this offer at any time.