Human corpus luteum physiology and the luteal-phase dysfunction associated with ovarian stimulation

The human corpus luteum is a temporary endocrine gland that develops after ovulation from the ruptured follicle during the luteal phase. It is an important contributor of steroid hormones, particularly progesterone, and is critical for the maintenance of early pregnancy. Luteal-phase dysfunction can result in premature regression of the gland, with a subsequent shift to an infertile cycle. Understanding the mechanism of steroidogenesis during corpus luteum growth and regression is crucial for evaluating the normal physiology and pathophysiology of reproductive cycles. The rate-limiting step in corpus luteum steroidogenesis is the transport of cholesterol to the site of steroid production. Steroidogenic acute regulatory protein is a key player in this process and is positively correlated with progesterone concentrations troughout the early an dmid-luteal phase. Changes in the endocrine environment brought on by the gonadotrophins used for ovarian stimulation are thought to underlie th

Pharmacokinetics of a single oral dose of 1.5-mg levonorgestrel when administered as 750-μg tablets or as 30-μg minipills

We examined the pharmacokinetics of a single dose of 1.5 mg of levonorgestrel when administered orally in two different formulations: two tablets of 0.75 mg or 50 minipills of 30 μg of levonorgestrel. Bioavailability of levonorgestrel with minipills was comparable to that with levonorgestrel tablets. These findings suggest that levonorgestrel-containing minipills can be considered as an alternative to standard levonorgestrel tablets for use in emergency contraception. © 2007 American Society for Reproductive Medicine

Decreased anti-Müllerian hormone concentration in follicular fluid of female smokers undergoing artificial reproductive techniques

Background: Several reports indicate that women who smoke have an increased risk of failure to conceive compared with their non-smoker counterparts. Here, we assessed the effect of smoking during the Assisted Reproduction Therapy (ART) on a potential marker of ovarian reserve, anti-müllerian hormone (AMH) in the follicular fluid (FF). Materials and Methods: This was a cohort prospective study to assess the association between cigarette smoking and AMH concentrations in FF in fifty-six women undergoing their first ART cycle. Self-reported smoking status over time was also collected through personal interview. The main outcome measured was the association between current smoking and AMH concentrations in FF. Smoking status was assessed by FF cotinine concentrations. Analysis of covariance was performed to test statistical interaction between the main outcome and confounders. Results: The mean concentration of AMH in follicular fluid was significantly decreased among smokers (1.02±0.14 v

Features of natural and gonadotropin-releasing hormone antagonist-induced corpus luteum regression and effects of in vivo human chorionic gonadotropin

Context: The natural process of luteolysis and luteal regression is induced by withdrawal of gonadotropin support. Objective: The objectives of this study were: 1) to compare the functional changes and apoptotic features of natural human luteal regression and induced luteal regression; 2) to define the ultrastructural characteristics of the corpus luteum at the time of natural luteal regression and induced luteal regression; and 3) to examine the effect of human chorionic gonadotropin (hCG) on the steroidogenic response and apoptotic markers within the regressing corpus luteum. Design: Twenty-three women with normal menstrual cycles undergoing tubal ligation donated corpus luteum at specific stages in the luteal phase. Some women received a GnRH antagonist prior to collection of corpus luteum, others received an injection of hCG with or without prior treatment with a GnRH antagonist. Main Outcome Measure: Main outcome measures were plasma hormone levels and analysis of excised luteal

Molecular modelling predicts that 2-methoxyestradiol disrupts HIF function by binding to the PAS-B domain

An estradiol metabolite, 2-methoxyestradiol (2ME), has emerged as an important regulator of ovarian physiology. 2ME is recognized as a potent anti-angiogenic agent in clinical trials and laboratory studies. However, little is known about its molecular actions and its endogenous targets. 2ME is produced by human ovarian cells during the normal menstrual cycle, being higher during regression of the corpus luteum, and is postulated to be involved in the anti-angiogenic process that plays out during luteolysis. We utilized cell biology techniques to understand the molecular mechanism of 2ME anti-angiogenic effects on human granulosa luteal cells. The principal effect of 2ME was to alter Hypoxia Inducible Factor 1A (HIF1A) sub-cellular localization. Molecular modelling and multiple bioinformatics tools indicated that 2ME impairs Hypoxia Inducible Factor complex (HIF) nuclear translocation by binding to a buried pocket in the HIF1A Per Arnt Sim (PAS)-B domain. Binding of 2ME to HIF1A

Ovarian Function in Adolescents Conceived Using Assisted Reproductive Technologies

© 2018 North American Society for Pediatric and Adolescent Gynecology Study Objective: To compare ovarian function between adolescents conceived using assisted reproductive technology (AcART) and adolescents who were conceived spontaneously (AcSP). Design: Multicenter study of ovarian function in AcART because of male or tubal infertility. Setting: University Hospital. Participants: We evaluated 22 AcART and 53 AcSP at 1-2 years after menarche. The participants were born at term (≥37 weeks of gestation) with normal birth weights (≥2500 g) from singleton pregnancies. Interventions: None. Main Outcome Measures: Differences in ovulation, reproductive hormones, and ovarian morphology. Results: AcART had an older age of menarche than that of AcSP, even after adjusting for maternal age at menarche, gestational age, and birth weight (P = .027). AcART had lower incidence of ovulation (P = .021) and higher luteinizing hormone serum levels (P = .01) than those of AcSP. The incidence of oligomen