follicular maturation
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Animals ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 3406
Author(s):  
Fabio De Rensis ◽  
Roberta Saleri ◽  
Irina Garcia-Ispierto ◽  
Rex Scaramuzzi ◽  
Fernando López-Gatius

Follicular organization starts during mid-to-late fetal life with the formation of primordial follicles. The bilateral interplay between the oocyte and adjoining somatic cells during follicular growth and ovulation may be sensitive to heat stress (HS). Mechanisms giving rise to pre-ovulatory temperature gradients across reproductive tissues are mostly regulated by the pre-ovulatory follicle, and because the cooling of the gonads and genital tract depends on a counter-current transfer system of heat, HS may be considered a major factor impairing ovulation, fertilization and early embryo development. There is evidence of a long-lasting influence of HS on oogenesis and final follicular maturation. Follicular stages that are susceptible to HS have not been precisely determined. Therefore, the aim of this review was to describe the influence of HS during the staged follicular development in dairy cattle, from the activation of primordial follicles to ovulation. Some clinical prospects are also considered.


2021 ◽  
Author(s):  
Yen-Ju Sung ◽  
Liang-Hsuan Chen ◽  
Tzu-Hsuan Chin ◽  
Shang-Yu Huang ◽  
Hsing-Tse Yu ◽  
...  

Abstract Background Evidently, when undergoing GnRH-antagonist protocols, dual trigger has proven to produce not just better quality and quantity of oocytes but also pregnancy outcome. However, not much comparative studies have been published when PPOS protocol is used for ovarian stimulation. Can the same positive outcomes be expected after the patients have been exposed to the high level of progesterone required for PPOS protocols? Methods In this retrospective cohort study, patients undergoing PPOS protocols were separated into three groups based on the method employed for triggering final follicular maturation, which included: (a) human chorionic gonadotropin (hCG); (b) Gonadotropin-releasing hormone-agonist (GnRH-agonist); or (c)dual trigger (GnRH-agonist + hCG). Either in vitro fertilization or intracytoplasmic sperm injection (IVF/ICSI) was utilized for fertilization. Assessment comprised of their dynamic hormone profiles, embryonic analysis, and clinical outcomes. Results Of the 344 recruited patients, those fulfilling the Bologna criteria as poor ovarian responders and showing Estradiol (E2)<1000 pg/ml on the day of triggering had higher oocyte maturation rate (82% vs 58%, p<0.05) when triggered with dual trigger (GnRH-agonist + hCG) than hCG alone. For the patients with E2> 6500 pg/ml on the day of triggering, none of the three triggering methods demonstrated a significant advantage regarding the number of oocytes, percentage of matured oocytes, and rate of oocytes at fertilization or cleavage stages. Conclusions Implementing dual trigger for stimulating final follicular maturation in patients undergoing PPOS protocols is debatable. For poor ovarian response (POR) patients, dual trigger appeared to yield higher percentage of matured oocytes. In contrast, for hyper-responders, methods of triggering oocyte maturation did not affect the percentage of matured oocytes or the qualities of the embryos. For this group of patients, therefore, the agent used should be one that would reduce the risks of ovarian hyper-stimulation syndrome (OHSS).


Author(s):  
Lawrence Hsu Lin ◽  
Andrea Hernandez ◽  
Alan Marcus ◽  
Fang-Ming Deng ◽  
Esther Adler

Context.— Gender-affirming surgery is part of a multidisciplinary approach in gender transitioning. Deeper histologic examination may strengthen care for transmasculine individuals and increase the understanding of the influence of hormonal therapy in specific organs. Objective.— To evaluate and catalogue histologic findings of tissue obtained from gender-affirming gynecologic surgery and cervical cytology specimens. Design.— This is an institutional review board–approved retrospective study that included transmasculine individuals who underwent gender-affirming gynecologic surgery from January 2015 to June 2020. All surgical gynecologic pathology and cervical cytology slides were reviewed by 2 pathologists. Results.— Fifty-five patients were included, which represented 40 uteri, 35 bilateral ovaries, 15 vaginectomy specimens, and 24 cervical cytology results. The median age was 27 years (range, 18–56) and 94% (50 of 53) of patients were receiving testosterone for at least 1 year. Seventy-five percent (30 of 40) of endometria were inactive, while 25% (10 of 40) showed evidence of cycling. Transitional cell metaplasia was the most common finding in the cervix (17 of 40) and vagina (15 of 15), reflecting a high percentage (4 of 24) of unsatisfactory or ASC-US (atypical squamous cells of undetermined significance) cervical cytologies. Prostatic-type glands were identified in 20% (8 of 40) of cervices and 67% (10 of 15) of vaginectomy specimens. Multiple bilateral cystic follicles and evidence of follicular maturation were present in 57% (20 of 35) of cases. Four cases showed paratubal epididymis-like mesonephric remnant hypertrophy. Conclusions.— A comprehensive evaluation of tissue from gender-affirming surgery increases knowledge of the changes following androgen therapy in transmasculine individuals and may contribute to optimal patient care by raising awareness of normal histologic variations in this population.


Author(s):  
Ida Björkgren ◽  
Dong Hwa Chung ◽  
Sarah Mendoza ◽  
Liliya Gabelev-Khasin ◽  
Natalie T. Petersen ◽  
...  

Mammalian female fertility is defined by a successful and strictly periodic ovarian cycle, which is under the control of gonadotropins and steroid hormones, particularly progesterone and estrogen. The latter two are produced by the ovaries that are engaged in controlled follicular growth, maturation, and release of the eggs, i.e., ovulation. The steroid hormones regulate ovarian cycles via genomic signaling, by altering gene transcription and protein synthesis. However, despite this well-studied mechanism, steroid hormones can also signal via direct, non-genomic action, by binding to their membrane receptors. Here we show, that the recently discovered membrane progesterone receptor α/β hydrolase domain-containing protein 2 (ABHD2) is highly expressed in mammalian ovaries where the protein plays a novel regulatory role in follicle maturation and the sexual cycle of females. Ablation of Abhd2 caused a dysregulation of the estrous cycle rhythm with females showing shortened luteal stages while remaining in the estrus stage for a longer time. Interestingly, the ovaries of Abhd2 knockout (KO) females resemble polycystic ovary morphology (PCOM) with a high number of atretic antral follicles that could be rescued with injection of gonadotropins. Such a procedure also allowed Abhd2 KO females to ovulate a significantly increased number of mature and fertile eggs in comparison with their wild-type littermates. These results suggest a novel regulatory role of ABHD2 as an important factor in non-genomic steroid regulation of the female reproductive cycle.


2021 ◽  
Vol 12 ◽  
Author(s):  
Kyriaki Papageorgiou ◽  
Eirini Mastora ◽  
Athanasios Zikopoulos ◽  
Maria E. Grigoriou ◽  
Ioannis Georgiou ◽  
...  

One of the most widely used types of assisted reproduction technology is the in vitro fertilization (IVF), in which women undergo controlled ovarian stimulation through the administration of the appropriate hormones to produce as many mature follicles, as possible. The most common hormone combination is the co-administration of gonadotropin-releasing hormone (GnRH) analogues with recombinant or urinary-derived follicle-stimulating hormone (FSH). In the last few years, scientists have begun to explore the effect that different gonadotropin preparations have on granulosa cells’ maturation and apoptosis, aiming to identify new predictive markers of oocyte quality and successful fertilization. Two major pathways that control the ovarian development, as well as the oocyte–granulosa cell communication and the follicular growth, are the PI3K/Akt/mTOR and the Hippo signaling. The purpose of this article is to briefly review the current knowledge about the effects that the different gonadotropins, used for ovulation induction, may exert in the biology of granulosa cells, focusing on the importance of these two pathways, which are crucial for follicular maturation. We believe that a better understanding of the influence that the various ovarian stimulation protocols have on these critical molecular cascades will be invaluable in choosing the best approach for a given patient, thereby avoiding cancelled cycles, reducing frustration and potential treatment-related complications, and increasing the pregnancy rate. Moreover, individualizing the treatment plan will help clinicians to better coordinate assisted reproductive technology (ART) programs, discuss the specific options with the couples undergoing IVF, and alleviate stress, thus making the IVF experience easier.


2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
K Michitaka ◽  
H Kitasaka ◽  
N Fukunaga ◽  
Y Asada

Abstract Study question What is the clinical outcome of oocytes recovered after 39 hours from ovulation inducing drug administration? Summary answer Oocytes obtained after 39 hours from follicular maturation triggering are equally viable to those obtained at the standard time of 36 hrs. What is known already In the clinical setting of ART, ovum pick-up (OPU) is generally performed around 36 hours after the administration of ovulation inducing drugs (OID). However, there are cases where OPU cannot be performed at this time often due to long operating lists. As the time elapsed between the administration of ovulation inducing drugs and OPU becomes longer, there is a concern about time-related oocyte aging. Nevertheless, there are few reports of clinical results of OPU after 36 hours from OID. Study design, size, duration We conducted a review of 1187 cycles and 1951 patients in which OPU and embryo transfer was performed in 2017–2018. All cycles underwent a ‘freeze-all’ of embryos and the transfer cycle was in the thawed embryo transfer cycle for all cases. Participants/materials, setting, methods The time from the administration of OID to the end of OPU was divided into 36h group and over 39h group and the MII and normal fertilization rate of oocytes obtained from OPU after ovarian stimulation were compared. After confirmation of fertilization, the D3 good-quality embryo and the D5 and 6 good-quality blastocyst rates of embryos that continued to be cultured and the pregnancy and miscarriage rates of cleavage-stage embryos and blastocyst transfers were compared. Main results and the role of chance The MII rate in the 36h and &gt;39h groups was 78.1% vs. 80.0%, and the normal fertilization rate was 77.9% vs. 78.1% (ICSI) and 65.4% vs. 67.6% (Conventional-IVF). The D3 good-quality embryo rate (good-quality embryos are embryos with less than 5% fragmentation in 7–9 cells and compaction with more than 50% adhesion between split spheres) was 21.8% vs. 25.3%, the D5 good-quality blastocyst rate (at least 3BB according to Gardner classification) was 33.6% vs. 40.1%, and the D6 good-quality blastocyst rate was 31.1% vs. 37.5%, all of which were not significantly different. The pregnancy rate for cleavage-stage embryo transfer was 26.6% vs. 6.7%, and the miscarriage rate was 25.3% vs. 42.9%, both of which were not significantly different. The pregnancy rate for blastocyst transfer was 45.4% vs. 50.0%, and the miscarriage rate was 22.2% vs. 20.0%, both of which were not significantly different. (The significance difference test was a χ-square test) Limitations, reasons for caution The study was a retrospective study. Wider implications of the findings: Even if OPU is conducted after 36h of the administration of OID, to the extreme range of 39h–41h, oocyte aging does not seem apparent and pregnancy outcomes are similar to the standard time interval of 36 hours. Trial registration number ‘not applicable’


2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Kai-Lun Hu ◽  
Siwen Wang ◽  
Xiaohang Ye ◽  
Dan Zhang ◽  
Sarah Hunt

Abstract Background Traditionally, final follicular maturation is triggered by a single bolus of human chorionic gonadotropin (hCG). This acts as a surrogate to the naturally occurring luteinizing hormone (LH) surge to induce luteinization of the granulosa cells, resumption of meiosis and final oocyte maturation. More recently, a bolus of gonadotropin-releasing hormone (GnRH) agonist in combination with hCG (dual trigger) has been suggested as an alternative regimen to achieve final follicular maturation. Methods This study was a systematic review and meta-analysis of randomized trials evaluating the effect of dual trigger versus hCG trigger for follicular maturation on pregnancy outcomes in women undergoing in vitro fertilization (IVF). The primary outcome was the live birth rate (LBR) per started cycle. Results A total of 1048 participants were included in the analysis, with 519 in the dual trigger group and 529 in the hCG trigger group. Dual trigger treatment was associated with a significantly higher LBR per started cycle compared with the hCG trigger treatment (risk ratio (RR) = 1.37 [1.07, 1.76], I2 = 0%, moderate evidence). There was a trend towards an increase in both ongoing pregnancy rate (RR = 1.34 [0.96, 1.89], I2 = 0%, low evidence) and implantation rate (RR = 1.31 [0.90, 1.91], I2 = 76%, low evidence) with dual trigger treatment compared with hCG trigger treatment. Dual trigger treatment was associated with a significant increase in clinical pregnancy rate (RR = 1.29 [1.10, 1.52], I2 = 13%, low evidence), number of oocytes collected (mean difference (MD) = 1.52 [0.59, 2.46), I2 = 53%, low evidence), number of mature oocytes collected (MD = 1.01 [0.43, 1.58], I2 = 18%, low evidence), number of fertilized oocytes (MD = 0.73 [0.16, 1.30], I2 = 7%, low evidence) and significantly more usable embryos (MD = 0.90 [0.42, 1.38], I2 = 0%, low evidence). Conclusion Dual trigger treatment with GnRH agonist and HCG is associated with an increased live birth rate compared with conventional hCG trigger. Trial registration CRD42020204452.


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