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Ultrasonography in Bovine Gynecology
Published in Juan Carlos Gardón, Katy Satué, Biotechnologies Applied to Animal Reproduction, 2020
Giovanni Gnemmi, Juan Carlos Gardón, Cristina Maraboli
There is still much talk of lutein cysts, but what is the real importance of these structures? How many of these alleged cysts are not actually a cavitary corpus luteum or a follicular cyst in the process of luteinization?
Ultrasonic Monitoring of Follicular Growth and Ovulation in Spontaneous and Stimulated Cycles
Published in Asim Kurjak, Ultrasound and Infertility, 2020
An interesting observation was the blunted midcycle LH surge and the absence of a normal progesterone increase in conjunction with gonadotrophin surge. Absence of the preovulatory progesterone increase seems to be a primary event, since it is known that a preovulatory rise of progesterone is required for the full expression of LH surge.47 Pathophysiological examination of the unruptured follicle revealed complete luteinization. The oocyte within the follicle was immature and arrested in the first meiotic division.46
The Role of Eicosanoids in Menstruation and Disorders of Menstruation
Published in Murray D. Mitchell, Eicosanoids in Reproduction, 2020
The “normal menstrual cycle” refers to an ovulatory cycle in which follicular development is associated with increasing levels of peripheral estradiol, followed by a surge of luteinizing hormone (LH) at mid-cycle and ovulation. In the luteal phase, luteinization of the follicles causes the release of estradiol and progesterone from the corpus luteum. In the presence of regular cycles, ovulation will occur in 93% of women.6 Menstrual bleeding will occur when estradiol or progesterone is withdrawn from the endometrium, although the most predictable response is only achieved when progesterone is removed from an estradiolprimed endometrium. The effects of the ovarian steroids on epithelial and stromal proliferation and differentiation in the endometrium during the cycle have been described in detail elsewhere.78
Effect of elevated progesterone levels the day before ovulation on pregnancy outcomes in natural cycles of frozen thawed embryo transfer
Published in Gynecological Endocrinology, 2022
Di Wu, Ting Yu, Hao Shi, Jun Zhai
A comparison of the basic characteristics between the two groups showed that the AMH level, AFC, follicle diameter, and estrogen level the day before ovulation were higher in the PE than in the NP group, which suggested better ovarian reserve function in the PE group. The follicles do not secrete progesterone during the follicular phase, but the progesterone levels may be slightly elevated prior to ovulation. The mechanism underlying elevated progesterone levels before ovulation involves extensive vascularization and inflammation within the follicles, as larger follicles are found to alleviate hypoxia [18]. Dozortsev et al. showed that changes in the intrafollicular environment released some of the granulosa cells from the luteinization block; however, the alleviated hypoxic milieu reduced the ability of endothelin-1 to inhibit progesterone, thus, resulting in increased progesterone synthesis. When the progesterone levels rose above 0.5 ng/mL before ovulation, positive feedback acted on the hypothalamus to regulate the secretion of FSH and LH and eventually trigger ovulation [18]. LH causes rapid luteinisation of the follicles and an increase in progesterone levels >1.0 ng/mL [19]. We speculate that female individuals with larger pre-ovulatory follicle diameters and better ovarian function may produce more progesterone from luteinized granulosa cells.
Fertility preservation immediately after therapeutic abortion results in multiple normal follicular growth with the absence of mature oocytes due to early luteinization: a case report and literature review
Published in Gynecological Endocrinology, 2021
Haru Hamada, Tomonari Hayama, Akifumi Ijuin, Ai Miyakoshi, Michi Kasai, Shiori Tochihara, Marina Saito, Mayuko Nishi, Hiroe Ueno, Mizuki Yamamoto, Mitsuru Komeya, Yasushi Yumura, Hideya Sakakibara, Etsuko Miyagi, Mariko Murase
In general, the titer of hCG is 4–7 times higher than that of LH. The LH surge is approximately 100 mIU/mL. This level is equivalent to approximately 20 mIU/mL of hCG [14]. It is speculated that early luteinization may be prevented if hCG levels are less than 20 mIU/mL at the time of follicle development. Higher hCG levels during COS induced normal folliculogenesis in our patient. However, hCG continuously stimulated the LH receptors of follicular cells and induced early luteinization and degenerated oocytes. This suggests that obtaining frozen embryos with COS after the termination of pregnancy should be postponed until the hCG level decreases to <100 mIU/mL. In circumstances where there is not enough time to wait until the hCG level decreases, we suggest that oocyte retrieval be performed at the signal for luteinization with frequent monitoring of the P4 level, even if the follicles are small.
Luteinized thecomatosis and other conditions associated with sclerosing peritonitis: a problem in causation, management, and nomenclature
Published in Expert Review of Anticancer Therapy, 2021
In 1994, Clement et al. [1] reported the first 6 cases of the syndrome under discussion as luteinized thecoma associated with sclerosing peritonitis despite the fact that the term luteinized thecoma had previously been applied to a well-established neoplasm with an identical name by some of the same authors in 1982 [2]. Nevertheless, in their original article, the authors expressed a considerable degree of doubt regarding their conclusion as they stated that a closely related hyperplasia with luteinization instead of early neoplasia could not be excluded in four cases that had only slight ovarian enlargement or prominent entrapment of follicles. These early reports have resulted in a widespread belief that the ovarian lesions are neoplastic, and this conception is now deeply entrenched in the literature.