In cattle and other species, the corpus luteum plays a central role in the regulation of cyclicity and maintenance of pregnancy. In the absence of fertilization and implantation, the corpus luteum undergoes functional and morphological regression or luteolysis. Luteal regression is initiated in domestic ruminants by surges of prostaglandin F2alpha (PGF2alpha) from the uterus. Despite intensive ...

The present study evaluated whether the luteal phase elevation of body temperature would be offset during exercise by increased sweating, when women are normally hydrated. Eleven women performed 60 min of cycling exercise at 60% of their maximal work load at 32 degrees C and 80% relative air humidity. Each subject participated in two identical experimental sessions: one during the follicular ph...

Background. The aim of this pilot study was to evaluate intranasal buserelin for luteal phase support and compare its efficacy with standard vaginal progesterone in IVF/ICSI antagonist cycles. Methods. This is a prospective, randomized, open, parallel group study. Forty patients underwent ovarian hyperstimulation with human menopausal gonadotropin under pituitary inhibition with gonadotropin-re...

BACKGROUND The use of progesterone for luteal support has been demonstrated to be beneficial in assisted reproductive cycles, yet the optimal route of progesterone administration has still not been established. This article is a retrospective study in a tertiary reproductive medical unit to compare luteal progesterone supplementation with vaginal gel or intramuscular progesterone. METHODS A t...

The ability of bovine follicular fluid (FF) and oviduct fluid (ODF) to capacitate sperm was determined. At concentrations of greater than 20%, both FF and ODF capacitated sperm within 4 hours, but at concentrations greater than 40%, FF also initiated the acrosome reaction. Non-luteal ODF at a concentration greater than 60% capacitated sperm within 2 hours. Non-luteal ODF maintained sperm motili...

BACKGROUND GnRH agonist (GnRHa) triggering has been shown to significantly reduce the occurrence of ovarian hyperstimulation syndrome (OHSS) compared with hCG triggering; however, initially a poor reproductive outcome was reported after GnRHa triggering, due to an apparently uncorrectable luteal phase deficiency. Therefore, the challenge has been to rescue the luteal phase. Studies now report a...

A review of the current state of knowledge of oxytocin production by the preovulatory follicle and corpus luteum is presented. Corpora lutea of a number of mammalian species have been found to synthesize oxytocin. However, the synthesis and secretion of this nanopeptide by the corpus luteum of the ruminant has been most extensively studied because of the potential role of this peptide in facili...

Introduction: Gonadotropin inhibitory hormone (GnIH) has been known as a key inhibitor of the secretion of gonadotropin releasing hormone (GnRH). Ewe has estrous cycles comprising of follicular and luteal phases. Follicular phase is in turn divided into proestrous and estrous phases. Blood level of LH increases in follicular and decreases in luteal phases. The aim of the present study was to...

This is a prospeve randomised study designed to clarify the impact of various luteal support regimes (HCG and progesterone) on progesterone profiles and pregnancy outcomes. This study involved subjects undergone down regulated. stimulated IVF cycles using various types of luteal support, namely: Cyclogest (n=35). Crinone gel (n=36), various doses of Utrogestan (n=55) and HCG (n=35). Various dos...

The objectives of this study were to separate plasma lipoprotein particles based on the presence (low-density lipoproteins; LDL) or absence of apolipoprotein B (high-density lipoproteins; HDL) and to compare the abilities of bovine LDL and HDL to stimulate progesterone production by bovine luteal cells in culture. Plasma lipoproteins were isolated by ultracentrifugation and separated into LDL a...