Principles of Pathophysiology of Infertility Assessment and Treatment*
Asim Kurjak in Ultrasound and Infertility, 2020
A variety of treatment schedules for gonadotropin administration for induction of ovulation have been devised. Nearly all of those schedules are based on the fact that treatment with gonadotropin preparations results specifically in follicular growth and maturation. The “variable technique” has been used more commonly; the daily dosage and duration of therapy depend on individual response. Gonadotropin preparations are very active agents for stimulating the ovary to ovulate, and with adequate therapy ovulation is achieved in 80 to 90% of the patients, although pregnancy can be expected in only 40 to 60%. The conception rate depends on the selection of patients, dose, regimen, and number of treatment cycles. Gonadotropin therapy can be applied in combination with different agents like clomiphene, Gn-RH, dexamethasone, and parlodel.
Use of Luteal Phase Support
Botros Rizk, Yakoub Khalaf in Controversies in Assisted Reproduction, 2020
Whereas in a natural cycle with the development of a single dominant follicle midfollicular FSH levels are declining toward ovulation (7), in ovarian stimulation for in vitro fertilization (IVF), multifollicular development is achieved by administration of high daily gonadotropin concentrations. Stimulation dosage usually remains unchanged throughout the stimulation duration, unless the patient's individual response requires a change in the dosage. Therefore, ovarian stimulation will result in a large number of growing follicles, and each follicle contributes to the progesterone in the systemic circulation. Progesterone concentration often reflects the number of preovulatory follicles, and patients with high estradiol concentrations have significantly more oocytes and significantly higher progesterone concentrations (8).
The Stimulation of Steroid Biosynthesis by Luteinizing Hormone
Mario Ascoli in Luteinizing Hormone Action and Receptors, 2019
Gonadotropins (luteinizing hormone [LH]) and follicle stimulating hormone (FSH) regulate the biosynthesis of steroid hormones in gonadal cells. This chapter describes the important steps in steroid hormone biosynthesis in the cells of the ovary and testis, with particular emphasis on the sites that are responsive to LH action. LH or its analog, human chorionic gonadotropin (hCG), can increase steroid production acutely as well as by trophic stimulation. Both the acute and the trophic effects of LH/hCG appear to be mediated mostly, if not entirely, by increases in cyclic AMP. The trophic effects involve an increase in steroid biosynthetic enzymes, as well as an increase in membrane receptors for lipoprotein particles which can deliver the substrate, cholesterol, to the cell to be further metabolized to active steroid hormones. The most likely effect of acute LH stimulation is to increase the rate of association of the substrate, cholesterol, with the mitochondrial side-chain cleavage enzyme, as has been reported for ACTH in adrenal cells.1,2 However, the exact mechanism(s) by which acute or trophic stimulation occurs remains to be elucidated.
DuoStim protocol- a novel fertility preservation strategy for female oncology patients
Published in Human Fertility, 2023
Sarah J. Puthur, Susan Tracey, Della Gould, Cheryl T. Fitzgerald
The likelihood of a successful future live birth following oocyte storage is dependent on the age of the woman at the time of oocyte storage and the number of oocytes stored (Anderson et al., 2020). In a study by Cobo et al., a cohort of women aged 35 years and underachieved a cumulative live birth rate of 42.8% after the storage of ten oocytes. This reduced to 25.2% in women aged 36 years and over who stored the same number (Cobo et al., 2018). As the chance of future pregnancy increases with an increased number of stored oocytes, fertility preservation patients tend to be stimulated using higher doses of gonadotrophins. While higher gonadotrophin doses promote multiple follicular developments, it carries the risk of inducing ovarian hyperstimulation syndrome (OHSS) (Practice Committee of the American Society for Reproductive Medicine, 2019). OHSS can have a significant impact as it can disrupt planned cancer therapy (Practice Committee of the American Society for Reproductive Medicine, 2019).
Progesterone elevation on the day of oocyte retrieval and live birth rate after in vitro fertilisation treatment
Published in Journal of Obstetrics and Gynaecology, 2022
Maria Angeles Roque Fernandez, Cristina Alvarez Lleo, Esteban Gonzalez Mirasol, Maria Resta Serra, Carmen Garcia Garrido, María Sanchez Toledo, Antonio Amezcua Recover
Stimulation protocols used included GnRH long agonist, and GnRH antagonist. Ovarian stimulation was carried out by administering an individualised dose of gonadotropins based on the patient’s characteristics and causes of sterility. Both recombinant and urinary gonadotropins have been used and administered alone or in combination. The cycle control was carried out by counting and measuring the follicles and serum oestradiol concentration, adjusting the dose according to patient’s response. When at least three follicles were a diameter of 18 mm, 250 µg dose of recombinant hCG (hCG-r) (Ovitrelle©, Merck-Serono, Madrid, Spain) was administered, with oocytes retrieval performed 34–36 hours later by transvaginal ultrasound guidance. Conventional IVF or ICSI procedures were used for oocyte fertilisation. The embryos were classified following the ASEBIR (2015) criteria (Association for the Study of the Biology of Reproduction) in type A, B, C and D, considering good quality type A and B. The number and the day of embryos transferred was individualised depending on the clinical aspects and quality of embryos. According to our legislation, we transferred no more than 3 embryos. All patients received luteal phase support, according to our unit protocol, with 600 mg of vaginal micronized P (Utrogestan®, SEID laboratory, Barcelona, Spain, Progeffik®, Effik laboratory, Madrid, Spain) or subcutaneous daily P injection (Prolutex®, IBSA Farmaceutici, Lodi, Italy), performing the embryo transfer on day 2–3.
Influences of ovarian hormones on physiological responses to cold in women
Published in Temperature, 2022
Andrew M. Greenfield, Nisha Charkoudian, Billie K. Alba
While the roles of estrogens and progesterone are more thoroughly described, follicle stimulating hormone (FSH) may also influence BAT thermogenesis. FSH is a gonadotropic hormone produced by the anterior pituitary gland that stimulates the growth of ovarian follicles [176]. FSH begins to rise at the end of the luteal phase and continues in the early follicular phase, with a rapid rise in the pre-ovulatory phase [177]. In rodents, FSH influences energy metabolism by stimulating adipocyte lipid biosynthesis [178]. Interestingly, there is new evidence to suggest that FSH negatively regulates BAT thermogenesis, such that FSH blockade increases BAT activation and thermogenesis in mice [179]. This finding is supported by data demonstrating that FSH inhibits adipocyte UCP1 expression through reduced cAMP signaling [180]. However, no mechanistic studies examining FSH in humans with regard to BAT or thermoregulation have been performed. Therefore, significant research questions remain to whether there is a potential modulation of thermoregulatory function by FSH across the menstrual cycle.
Related Knowledge Centers
- Anterior Pituitary
- Chorion
- Chorionic Gonadotropin
- Luteinizing Hormone
- Placenta
- Glycoprotein
- Hormone
- Gonadotropic Cell
- Follicle-Stimulating Hormone
- Chorionic Gonadotropin
- Equine Chorionic Gonadotropin