Reviews on Reproductive Biology and Medicine

Recent developments in stem cell technologies have made significant advancements in the field of in vitro gametogenesis. In vitro gametogenesis (IVG) is a promising technology where functional gametes (sperm or egg cells) can be generated from stem cells. Scientists have made continuous advancements in the field and successfully derived fully functional sperm from stem cells in mice. Two recent papers generated excitement in IVG by generating bi-maternal and bi-paternal mice from embryonic stem cells (ESCs) and pluripotent stem cells (PSCs). IVG is a promising technology with potential applications that include infertility treatment, fertility preservation, same-sex reproduction, bypassing oocyte depletion in women with advanced age, conservation biology, genetic disorder prevention, and research into human germ cell development. In vitro spermatogenesis (IVS) is the attempt to recreate the process of spermatogenesis in a culture system. Spermatogenesis is essential for male fertility and reproductive health, but it can be impaired by various factors such as genetic defects, environmental toxicants, infections, aging, or medical therapies. Spermatogenesis is a complex and highly regulated process involving multiple cell proliferation, differentiation, and maturation stages. The main challenges of IVS are to provide a suitable microenvironment that mimics the testis in vivo, to support the survival and development of all the cell types involved in spermatogenesis, and to achieve complete and functional spermatogenesis. Therefore, there is a great interest in developing methods to study spermatogenesis in vitro, both for basic research and clinical applications. This review covers recent developments in in vitro spermatogenesis in the past two years. Advances in tissue engineering and regenerative medicine have introduced techniques like ex vivo tissue culture and technologies such as bioreactors, microfluidic systems, and organoids. Bioreactors and microfluidic systems replicate physiological conditions for tissue and cell cultivation, while organoids model organ functionality. Meanwhile, scaffolds, made from various materials, provide essential structural support, guiding the growth and organization of cells into functional tissues. Full article

Inflammatory bowel disease (IBD) frequently affects women of childbearing age and often coincides with pregnancy. With an increased incidence of IBD, gastroenterologists and obstetricians are more frequently involved in caring for women of reproductive age. While the development of novel therapies has allowed for successful conception and pregnancy outcomes, many patients may hesitate to conceive due to concerns for presumed adverse IBD effects on maternal and fetal health. As such, a noticeable percentage of patients may choose voluntary childlessness. Indeed, active IBD carries a greater risk of adverse pregnancy outcomes, including a loss of pregnancy, preterm delivery, and emergent C-sections. However, those with a quiescent disease tend to have fewer pregnancy complications. Therefore, it is essential to achieve remission prior to conception to optimize pregnancy outcomes. Dedicated IBD and pregnancy clinics can greatly assist in improving patient knowledge and attitudes towards pregnancy; through individualized pre-conception counseling, education, and medication adherence, the risks of poor pregnancy outcomes can be minimized. Furthermore, it is important for healthcare providers to have a sufficient understanding of the medication safety and tools to measure the disease activity, while counseling patients during gestation and breastfeeding periods. This review article aims to provide the most recent evidence-based management methods for IBD during pregnancy. Full article