What is kisspeptin? Kisspeptin is a peptide encoded by the KISS1 gene and it was first identified in 1996 (1). The first studies on kisspeptin were conducted in the field of oncology, where the KISS1 gene was first discovered and found to be expressed in malignant melanoma cells. Kisspeptin was originally known as “metastatin” on […]

Introduction Premature ovarian insufficiency (POI) refers to a decrease in ovarian function before the age of 40 and it affects approximately 1% of all women 1. Estradiol is frequently decreased (below 50 pmol/L) in affected women, while gonadotropins are elevated; women report menstrual changes ranging from irregular cycles to amenorrhea 2. In the literature, various […]

Introduction Diapause, a survival mechanism that represents an intermediate step between fertilization and embryo implantation, is reported to occur in >130 mammalian species. Delayed implantation extends gestation duration in 70% of eutherian and ~30% of marsupial species 1. Although the embryo transits and reaches the uterus, it does not implant. The length of the implantation […]

Introduction Endometrial receptivity and implantation failure remains an unsolved enigma of the 20 million years of human life on our planet. Way of life, work or occupation, eating habits, re­lationship with partner, exposure to environmental toxins, physical activities etc., influence endocrine, psychological, immunological systems, changing the genome and influencing endometrial receptivity. Endometrial receptivity is orchestrat­ed […]

Introduction Leydig cell tumor is an uncommon clinical entity and accounts for less than 0.1% of all ovarian tumors [1, 2]. These tumors are usually unilateral and benign [3, 4]. Leydig cell tumors are functional tumors, which lead to hyperandrogenism and virilization as a consequence of high production of testosterone. Symptoms and signs may include […]

Introduction Surrogacy means that a woman becomes pregnant and gives birth to a child with the intention of giving this child to another person or couple, commonly referred to as the ‘intended’ or ‘commissioning’ parents. [1]   A surrogate mother is the woman who carries and gives birth to the child, and the intended parent is […]

Introduction Nowadays, more than 3% of infants born in developed countries are conceived through assisted reproductive technology (ART) [1]. It has been suggested that ART pregnancies are related to poorer pregnancy outcomes compared with natural conceptions [2,3]. Recent studies have shown that singleton pregnancies after in vitro fertilization (IVF) treatment have an increased risk of […]

Introduction Premature ovarian insufficiency (POI) is a disease characterized by oligomenorrhea, hypoestrogenism and a follicle-stimulating hormone (FSH) level higher than 25 IU/L that occurs in women younger than 40 years of age.[1,2] It has been suggested that POI may affect 1% of women under 40.[1,3,4] The term POI has replaced the older “premature ovarian failure” […]

Introduction Turner syndrome (TS) occurs in 1 in 2500 births and involves the complete or partial loss of one X chromosome (deletions, translocations, inversions, isochromosomes, and mosaicisms)1. TS is characterised by hypergonadotropic hypogonadism. Affected women are usually born with a normal number of primordial follicles that undergo accelerated atresia2. The majority of cases have primary […]

Introduction Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the third recorded highly pathogenic coronavirus infecting humans, and the first to cause a global pandemic 1. This exceptionally insidious virus displays three main features: high rates of infection; high rates of mutation (typical of single-stranded RNA viruses); and the ability to infect multiple organs in […]

Introduction Polycystic ovary syndrome (PCOS), which is common worldwide, is an endocrine condition characterized by chronic anovulation, clinical and/or biochemical hyperandrogenism, and/or polycystic ovaries [1]. Many experts consider hyperandrogenism to be the main characteristic of PCOS. Several theories propound different mechanisms to explain PCOS manifestations: (i) a primary enzymatic defect in ovarian and/or adrenal steroidogenesis; […]

Introduction Anorexia nervosa (AN) is a serious eating disorder. A distorted self-perception of body image and an excessive fear of gaining weight result in restrictive eating habits and extreme underweight. On top of decreased body mass index (BMI), a number of other criteria are used to establish a diagnosis of AN [1]. The prevalence of […]

Introduction Background Premature ovarian insufficiency (POI) is a clinical syndrome characterized by the loss of ovarian activity before the age of 40; it is associated with hypoestrogenism and oligo- or amenorrhea 1. POI can have different etiopathogenetic causes: it can be iatrogenic, as after chemotherapy and radiotherapy or surgery, but it can also be associated […]

 Introduction Adrenal gland secreted stress hormones such as cortisol & DHEA-S play an important role during pregnancy and parturition [1-4]. However, imbalance of maternal cortisol levels due to prenatal stress or adrenal insufficiency can lead to complications in pregnancy and poor birth outcome, including preterm birth and infants born with low birth weight [3]. Some […]

Introduction Endometriosis is defined as the presence of endometrial glands and stroma outside the uterine cavity, predominantly, but not exclusively, in the pelvic compartment. It is an oestrogen-dependent chronic inflammatory condition that affects women of reproductive age, and it is associated with pelvic pain and infertility [1]. Endometriosis is one of the most controversial diseases […]

Introduction   The use of oocyte donation in the treatment of infertility has increased constantly in recent years (1). The main indications for the use of egg donation, proposed by the American Society for Reproductive Medicine, include primary ovarian failure, prevention of genetic diseases in offspring, decreased ovarian function, persistence of poor oocyte/embryo quality, and […]

Introduction Menstruation, a natural physiological phenomenon, includes proliferation and desquamation of the uterine endometrium on a monthly, repetitive basis [1]. Regular menstrual cycles offer a window into women’s overall reproductive health. A majority of women from all cultures and socioeconomic levels, however, experience regular recurrence of various symptoms during the days prior to menstruation, with […]

Introduction Acne vulgaris, or acne, is a common skin condition that affects 9.4% of the world population [1]. More than 85% of adolescents suffer from acne, which is moderate to severe in about 15–20% of patients [2]. Acne often persists into adulthood. 64% of individuals in their 20s and 43% of individuals in their 30s […]

Introduction Abnormal uterine bleeding (AUB) occurs in approximately 5% of postmenopausal women. Since 7 to 9% of AUB cases are due to endometrial cancer, the primary aim of the evaluation in all post-menopausal women with AUB is to exclude malignancy. (1,2) Ovarian carcinoma is the third most common gynecologic cancer. Epithelial tumors account for 95% […]

Introduction Vitamin D is a steroid hormone. Around of 80-90% of our vitamin D is synthesized in the skin through sunlight exposure; the rest derives from food1. It is well established that vitamin D maintains calcium homeostasis and promotes bone mineralization1. However, increasing evidence suggests that there are also several non-skeletal benefits of vitamin D. […]

Introduction Premature ovarian insufficiency (POI) was formerly known as premature ovarian failure (POF), a term which referred to the cessation of ovarian function before the expected age of natural menopause (1). It has been questioned whether the old term, “ovarian failure”, is correct, since a significant percentage of affected women have evidence of follicular activity, […]

Background and Purpose In in vitro fertilization (IVF) cycles, various ovarian stimulation protocols are used with the aim of obtaining a sufficient number of oocytes. However, these protocols often do not achieve the desired result. Patients with low ovarian reserve and insufficient response to ovarian stimulation, unfortunately, constitute the most numerous cohorts in IVF clinics. […]

Introduction Hypoestrogenism and hyperinsulinism are independent risk factors for metabolic syndrome, dyslipidemia, endothelial dysfunction, inflammation, autonomic system disturbances, cardiovascular diseases, etc.[1]. Insulin resistance is defined as decreased sensitivity and/or responsiveness to the metabolic action of insulin, responsible for promoting glucose disposal. The etiology of insulin resistance can be: genetic (mutations in the insulin receptor gene, […]

Introduction The composition of the vaginal microbiome is dynamic and undergoes several changes corresponding with hormonal fluctuations throughout a woman’s reproductive life. The vagina harbors several microorganisms that exist in a regulated and mutualistic relationship within the microbiome (1). The composition of the bacterial species in the vaginal microbiome changes significantly in response to several […]

Introduction Cohort studies estimated that premature ovarian insufficiency (POI), diagnosed before 40 years of age, occurs in around 1% of women, whereas women with early menopause (EM), which occurs before the age of 45 years, is found in around 5% [1-3]. A recent meta-analysis of worldwide data reported a pooled prevalence of 3.7% for POI […]