A Matter of Time: Delayed Presentation and Rapid Progression from Gonadotropin-Independent to Gonadotropin-Dependent Precocious Puberty following Successful Treatment for a Leydig Cell Tumor

Leydig cell tumors, most often benign, are a rare cause of isosexual gonadotropin-independent precocious puberty in boys due to secretion of testosterone. Very rarely do these tumors produce estrogen, causing gynecomastia. Testicular sparing surgery is the mainstay of treatment currently although radical orchidectomy was the choice in the past. Following surgery, clinical signs improve along with a revision of biochemical changes. Occasionally, it has been reported few children are progressed to gonadotropin-dependent precocious puberty (GDPP) after initial clinical and biochemical recovery. Gonadotropin receptor analogs have been successful on them to halt the progression of puberty, and growth hormone administration has been used to optimize the adult height. Here, we report a case of a 10-year-old boy who presented very late due to failure in recognition of features of puberty due to a Leydig cell tumor. Even though he underwent successful radical orchidectomy, just within 1 month following surgery, he entered GDPP in contrast to the published cases where it was earliest detected at 3 months.

Implantation Failures and Miscarriages in Frozen Embryo Transfers Timed in Hormone Replacement Cycles (HRT): A Narrative Review

The recent advent of embryo vitrification and its remarkable efficacy has focused interest on the quality of hormone administration for priming frozen embryo transfers (FETs). Products available for progesterone administration have only been tested in fresh assisted reproduction technologies (ARTs) and not in FET. Recently, there have been numerous concordant reports pointing at the inefficacy of vaginal preparations at delivering sufficient progesterone levels in a sizable fraction of FET patients. The options available for coping with these shortcomings of vaginal progesterone include (i) rescue options with the addition of injectable subcutaneous (SC) progesterone at the dose of 25 mg/day administered either solely to women whose circulating progesterone is <10 ng/mL or to all in a combo option and (ii) the exclusive administration of SC progesterone at the dose of 25 mg BID. The wider use of segmented ART accompanied with FET forces hormone replacement regimens used for priming endometrial receptivity to be adjusted in order to optimize ART outcomes.

The effectiveness of prostaglandin nanoparticles in corpus luteum regression

Research examined the formation of prostaglandin nanoparticles and their effect on corpus luteum (CL) regression carried out at IRIAP. The nanoparticles formation was carried out using the ionic gelation method. The nanoparticles have a particle size of 316.80±0.14 nm, polydispersion index of 0,453±0,001, zeta potential of +17,40±0,85 mV with 69,69±8.81% hormone entrapment. The effectiveness of nanoparticle in CL regression was observed (prostaglandin vs prostaglandin nanoparticles) using ultrasound observation, hormone profile and estrus response. Further, the size of the ovulating follicle, the time of ovulation, the size of the CL and the onset of estrus after the administration of the prostaglandins were observed. The observation showed that the intramuscular administration of prostaglandin and prostaglandin nanoparticles did not significantly differ on the onset of estrus, time of ovulation, the ovulating follicle size, size of CL and progesterone concentration. The onset of estrus occurred on 2.50 ± 0.58 and 2.33 ± 0.52 days, the ovulation time after hormone administration was on days 3.50 ± 0.55 and 2.83 ± 0.75 with the ovulation follicle size of 16, 62 ± 0.96 and 17.03 ± 1.13 mm, while the CL measures at H-3 were 13.56 ± 2.28 and 10.45 ± 0.88, the progesterone H-2 concentrations were 0.299 and 0.395, respectively for prostaglandin and prostaglandin nanoparticles. It can be concluded that the formation of nanoparticles did not impair the effectiveness of hormones in CL regression so that it can be used to increase the effectiveness of estrus synchronization

C57BL/6J mouse superovulation: schedule and age optimization to increase oocyte yield and reduce animal use

Superovulation protocols have been described for different mouse strains, however the numbers of animals used are still high and still little information is known about hormone administration schedules and estrous cycle phases. In this study, we aimed to optimize a superovulation protocol by injecting 5 IU of pregnant mare serum gonadotropin followed by 5 IU of hCG 48 h later, using three different schedules related to the beginning of the dark cycle (3, 5 and 7 pm) in a light cycle of 7 am to 7 pm, with light on at 7 am. C57BL/6J mice at 3, 4 and 5 weeks of age were used and the estrous cycle phase for times of PMSG and hCG injections was also analyzed. Total oocyte number was counted in the morning after hCG injection. Hormones given at 3 weeks of age at 3 pm (59 ± 15 oocytes) and 7 pm (61 ± 10 oocytes) produced a significantly higher oocyte number compared with oocytes numbers collected from females at the same age at 5 pm (P = 0.0004 and <0.0001 respectively). Females at 4 and 5 weeks of age produced higher numbers of oocytes when superovulated at 7 pm. No statistical differences between females at different phases of the estrous cycle were found. These results showed that in C57BL/6J mice, hormones should be given at 3 or 7 pm for females at 3 weeks of age, however older females should be superovulated closer to the beginning of the dark cycle to reduce female mouse use and increase the numbers of oocytes produced per female.