Individualized luteal phase support after fresh embryo transfer: unanswered questions, a review

An Overview of the Microbiota of the Human Urinary Tract in Health and Disease: Current Issues and Perspectives

This article is intended to deepen our knowledge to date regarding the functions of the resident microbiota/microbiome in the urinary system for human health and disease. First, we sought to report the general characteristics (composition and stability) of the normal urinary system microbiota in the different anatomical sites in relation to some factors such as the effect of age, gender and diet, analyzing in detail the functions and the composition of the microbiota in the light of current knowledge. Several pieces of evidence suggest the importance of preserving the micro-ecosystem of the urinary system, and in some cases their relationship with diseases is important for maintaining human health is well understood. The female and male reproductive microbiota have mainly been studied over the past decade. In the past, the arrest was thought to have taken place in a sterile environment. Microorganisms of the microbiota form biofilms, three-dimensional structures, that differ in the reproductive organs and interact with both gametes and the embryo as well as with maternal tissues. These biofilms from the reproductive system also interact with others, such as that of the gastrointestinal tract. Reduction in its diversity intestinal microbiota can disrupt estrogen metabolism and affect the reproductive microbiota. It is therefore understood that its quantitative and qualitative identification is important for microbiota, but also the study of the structures formed by the microorganisms. A dysbiosis with local or systemic causes can lead to serious diseases. The role of probiotics in maintaining microbial population harmony (eubiosis) and preventing certain pathologies of the urinary and reproductive system was also investigated. A negative variation in the qualitative and quantitative composition of certain strains of microorganisms (dysbiosis) due to local or systemic causes can even lead to serious diseases. The role of probiotics in maintaining the healthy balance of microorganism populations (eubiosis), and thus in the prevention of certain pathologies of the urinary and reproductive system, has also been studied.

Addition of intramuscular to vaginal progesterone for luteal phase support in fresh embryo transfer cycles: A cross-sectional study

Background

Luteal phase deficiency is common in assisted reproductive technology and is characterized by inadequate progesterone production. Various studies have shown that administration of progesterone in fresh embryo transfer cycles increases the rate of clinical pregnancy and live birth rate. Progesterone administration has variable types: oral, vaginal, oil-based intramuscular, and subcutaneous.

Objective

This study aims to compare the effect of adding intramuscular progesterone to the vaginal progesterone for luteal phase support in the fresh embryo transfer cycle.

Materials and Methods

This study reviewed the information related to 355 women who had a fresh embryo transfer between March 2020 and February 2021 at the Yazd Reproductive Sciences Institute, Yazd, Iran. The participants population were divided into 2 groups based on the type of luteal phase support regime: group I (n = 173) received 400 mg vaginal progesterone alone twice a day from the day of ovum pick up; and group II (n = 182) received 50 mg IM of progesterone in addition to vaginal progesterone 400 mg twice a day from the day of ovum pick up. Chemical and clinical pregnancy rates were compared between groups.

Results

The basic characteristics of groups were statistically similar. The rates of chemical and clinical pregnancy were higher in the vaginal plus IM progesterone group than in the vaginal progesterone group. Moreover, chemical pregnancy showed a significant difference between the groups (p = 0.011).

Conclusion

Our findings demonstrated that the addition of IM progesterone to the vaginal progesterone improves the chemical pregnancy rate in fresh embryo transfer.

Molecular Clues to Understanding Causes of Human-Assisted Reproduction Treatment Failures and Possible Treatment Options

More than forty years after the first birth following in vitro fertilization (IVF), the success rates of IVF and of IVF-derived assisted reproduction techniques (ART) still remain relatively low. Interindividual differences between infertile couples and the nature of the problems underlying their infertility appear to be underestimated nowadays. Consequently, the molecular basis of each couple’s reproductive function and of its disturbances is needed to offer an individualized diagnostic and therapeutic approaches to each couple, instead of applying a standard or minimally adapted protocols to everybody. Interindividual differences include sperm and oocyte function and health status, early (preimplantation) embryonic development, the optimal window of uterine receptivity for the implanting embryo, the function of the corpus luteum as the main source of progesterone production during the first days of pregnancy, the timing of the subsequent luteoplacental shift in progesterone production, and aberrant reactions of the uterine immune cells to the implanting and recently implanted embryos. In this article, the molecular basis that underlies each of these abnormalities is reviewed and discussed, with the aim to design specific treatment options to be used for each of them.