Depo-Estradiol (estradiol cypionate) / Pfizer - LARVOL DELTA

A Case Series Examining the Use of Subcutaneous Estradiol for Feminization (ENDO 2025) - "40 patients who met 6 inclusion criteria were assessed: age ≥18 years old, received diagnosis ICD10 F64.0 (gender dysphoria/incongruence), prescribed estrogen formulation was solely SC estradiol cypionate or estradiol valerate, visited Hartford Healthcare Endocrinology between January 1, 2020 and March 7, 2023, completed at least two lab visits to establish baseline and also after initiation of therapy, and had at least one clinic visit to assess satisfaction. Ann Intern Med. 2018 Aug 21; 169(4):205-213."

Clinical • Cardiovascular • CNS Disorders • Endocrine Disorders

Efficacy of Short-Term Timed Artificial Insemination Protocols With Estradiol Esters and PGF2α in Girolando Cows. (PubMed, Reprod Domest Anim) - "Cows with POF ≥ 10 mm at D0 had significantly higher conception rates with EC than with EB (48.3% vs. 29.0%; p = 0.03). Both protocols were equally effective; however, EC was more advantageous for cows with a POF ≥ 10 mm at treatment initiation."

Clinical • Journal

Reproductive outcomes of prepubertal Bos indicus beef heifers raised in a feedlot system submitted or not to ovulation induction strategies prior to a timed-artificial insemination treatment regimen. (PubMed, Theriogenology) - "Reproductive outcomes were evaluated in prepubertal Nelore (Bos indicus) heifers submitted or not to two ovulation induction treatment regimens based on progesterone (P4) and estradiol treatments prior to the timed-artificial insemination (TAI)...The TAI was conducted 2 d later (Day 9, 46-50 h after P4 device withdrawal), concurrently with the administration of 8.4 μg of buserelin acetate...In conclusion, although the two ovulation induction treatments imposed prior to the synchronization for TAI resulted in a larger proportion of heifers with CL on Day 0, enhanced UT development and improved expression of estrus, there was no improvement in fertility outcomes of prepubertal Nelore heifers managed in a feedlot system. Interestingly, heifers that did not respond to the ovulation induction treatments (without CL on Day 0) were least fertile, indicating that these heifers were not in a peri-pubertal state, rather, the reproductive endocrine status of these..."

Journal

Luteal Function and Pregnancy Rate in Bos taurus Heifers Treated With GnRH Prior to Timed Artificial Insemination. (PubMed, Reprod Domest Anim) - "The study aimed to evaluate the effects of GnRH given 34 h after progesterone (P4) intravaginal device (IVD) removal in a timed artificial insemination (TAI) protocol. A significant effect of body weight (BW) and body condition score (BCS) on PR was observed for control (p< 0.05), but not for GnRH34. In conclusion, GnRH 34 h after the IVD removal in beef heifers previously treated with EC had no effect on luteal function and fertility."

Journal

Transcriptomic analysis of heifers according to antral follicle count. (PubMed, Theriogenology) - "However, a tendency of a higher amount of grade II COCs was observed in heifers with high AFC than in those with low AFC. RNA sequencing results indicated that the main differences between high and low AFC heifers were not reflected in the genes directly related to fertility."

Journal • CAB39 • CD81 • CITED2 • FDX1

Influence of the follicular wave on gene expression and in vitro embryo production in cattle. (PubMed, Theriogenology) - "Twenty Bos taurus taurus donors were subjected to ovulation synchronization, starting with intramuscular administration of 2 mg estradiol benzoate and a 1.9 g intravaginal progesterone device on a random estrous cycle day (ten days before synchronized ovulation; D-10). Oocytes from G18 showed upregulation of genes related to apoptosis control and lipid metabolism, whereas those from G4 and G8 were downregulated. In conclusion, ovum pick-up at the beginning of the second follicular wave can improve IVP efficiency."

Journal • Preclinical • Metabolic Disorders

Evaluation of progesterone device reuse in shortened ovulation synchronization protocol in buffaloes raised in Amazon. (PubMed, Trop Anim Health Prod) - "In conclusion, the study suggests that the use of P4 intravaginal device with low content proves to be more efficient in synchronizing the follicular wave in buffaloes. This information contributes to our understanding of reproductive efficiency in Bubalus bubalis, particularly in the unique conditions of the Amazon."

Journal

Revisiting Injectable Estrogen Dosing Recommendations for Gender-Affirming Hormone Therapy. (PubMed, Transgend Health) - "We note a concerning trend where patients are prescribed high-dose injections based on the guidelines leading to serum E2 levels well above the range recommended in the same guidelines. Our review indicates that 5 mg weekly or lower should be prescribed when initiating injectable estrogens to avoid supraphysiologic E2 levels."

Journal

Reproductive outcomes of lactating dairy cows submitted to first timed-artificial insemination protocols with different strategies to induce final ovulation. (PubMed, J Dairy Sci) - "A total of 909 lactating dairy cows from 6 dairy herds initiated a presynchronization protocol on d -15 with an intravaginal progesterone (P4) implant and 7 d later (d -8) were treated with 1.0 mg of estradiol cypionate (EC) and 0.530 mg of cloprostenol sodium (PGF), simultaneously with the P4 implant removal. On d 0, the protocol for synchronization of ovulation was initiated with 16.8 µg of buserelin acetate (GnRH) and insertion of a 2.0 g P4 implant, followed by a treatment with 0.530 mg of PGF on d 6, and a second PGF on d 7, concomitant with the P4 implant withdrawal...Fertility was greater in cows with CL at the time of the first PGF treatment than in cows without CL (45.9 vs. 17.7%). In summary, the strategies to induce final ovulation resulted in similar fertility despite the different physiological responses such as expression of estrus, but further research is needed to definitively confirm the relationship between lack of EC and increased pregnancy loss."

Journal

Fertility of predominantly Bos taurus beef cows exposed to fixed-time artificial insemination protocols with intravaginal inserts containing different amounts of progesterone. (PubMed, Theriogenology) - "In summary, intravaginal P4 inserts with only 0.5 g of P4 resulted in decreased circulating concentrations of P4 and decreased pregnancy rates. Delaying induction of luteolysis only partially mitigated this negative outcome."

Journal

Estrogens impair hypophagia and hypothalamic cell activation induced by vasoactive intestinal peptide, but not by pituitary adenylate cyclase-activating polypeptide. (PubMed, Peptides) - "Cell activation induced by VIP in ARC and PVN was blocked by estradiol. Therefore, estrogens disrupted the hypophagia induced by VIP, but not by PACAP, and these differences seem to be, at least in part, due to an impairment of the activation of the ARC-PVN pathway."

Journal • ADCYAP1

Evaluation of GnRH- versus estradiol-based protocols for ovulation synchronization in postpartum Bos taurus grazing beef cows submitted to fixed-time artificial insemination. (PubMed, Theriogenology) - "Cows were blocked according to presence/absence of a CL, body condition score, and days postpartum and assigned randomly to one of three treatments: I) 7-day EB (n = 368), estradiol benzoate (EB) and intravaginal progesterone-(P4)-releasing device (IVPD) on Day -10, prostaglandin F2α (PG), equine chorionic gonadotropin (eCG) and estradiol cypionate (ECP) at IVPD removal on Day -3 with FTAI done on Day -1 (54 ± 2 h after IVPD removal); II) 7-day GnRH (n = 367), GnRH at IVPD insertion on Day -10, PG and eCG at IVPD removal on Day -3 with GnRH and FTAI on Day 0 (66 ± 2 h after IVPD removal); and III) 7 & 7 GnRH (n = 361), PG at IVPD insertion on Day -17, GnRH on Day -10, IVPD removal, PG and eCG on Day -3 with GnRH and FTAI on Day 0 (66 ± 2 h after IVPD removal). Pregnancy per AI was greater (P < 0.05) in cows treated with the 7 & 7 GnRH (63.5 %) treatment..."

Journal • Review

Use of Injectable Progesterone as a Pre-Synchronisation Strategy in a Timed Artificial Insemination Protocol Based on Gonadotropin-Releasing Hormone and Progesterone in Bos indicus Beef Cows in Anoestrous. (PubMed, Reprod Domest Anim) - "On D0, the ovarian assessment was repeated, and TAI protocol was initiated in all animals, with the insertion of an intravaginal P4 device and administration of 10.5 μg of buserelin acetate (gonadotropin-releasing hormone-GnRH). The pregnancy rate was similar (p = 0.64) between groups and was not influenced by the CL rate on D7 (p = 0.48), oestrous expression (p = 0.20) or their interaction (p > 0.1). Pre-synchronisation effectively increased the proportion of cows with CL on D7 without altering the diameter of the largest follicle, oestrous expression or pregnancy rate in anoestrous cows treated with a GnRH/P4-based TAI protocol."

Clinical • Journal

Optimisation of Early Pregnancy Diagnosis and Resynchronisation in Beef Cows. (PubMed, Reprod Domest Anim) - "Cows treated with PGF had a P/AI of 30.0% compared with a 48.9% P/AI in controls (p = 0.06). Our findings demonstrate that the POF size affects the accuracy of a CLBF-based early pregnancy diagnosis and that the removal of PGF treatment from the resynchronisation protocol tended to increase P/AI of the second TAI."

Journal

Improving Milk Yield, Milk Quality, and Follicular Functionality Behavior in Dairy Cows from the Implementation of Microencapsulated Chili Pepper Supplements in Their Diets. (PubMed, Animals (Basel)) - "Animals were subject to an ovulation synchronization protocol on day 0 (D0), and an intravaginal progesterone (P4) implant, estradiol benzoate, and prostaglandin (PGF2α) were administered. There was a higher percentage of vascularization in the preovulatory follicle in the CP group (p ≥ 0.10). The findings show that the inclusion of MHCP in the diet of dairy cows does influence their milk production and reproduction."

Journal

Investigation of potential ascorbate peroxidase inhibitors for anti-leishmaniasis therapy. (PubMed, Folia Microbiol (Praha)) - "Overall, estradiol cypionate, cloxacillin sodium, cinchonidine, and quinine hydrochloride dihydrate all exhibited inhibitory effects on the APX enzyme of Leishmania donovani. These results suggest that further investigation is needed to explore the potential of developing novel anti-leishmaniasis drugs using these compounds."

Journal • Infectious Disease

The use of a recombinant equine chorionic gonadotropin (reCG) in fixed-time AI programs in beef cattle. (PubMed, Theriogenology) - "In conclusion, treatment with reCG improved fertility in suckled Bos taurus and Bos taurus x Bos indicus beef cows. In suckled Bos indicus cows, although treatment with reCG and serum derived eCG were comparable, the higher dosage of reCG was detrimental to their P/AI."

Journal

Bovine somatotropin increases the pregnancy rate in fixed-time artificial insemination in beef cattle. (PubMed, Reprod Domest Anim) - "This study evaluated the effect of bovine somatotropin (bST) on pregnancy rate (PR) and size of the dominant follicle (DF) on the day of intravaginal progesterone (P4) removal in protocols for fixed-time artificial insemination (FTAI). The eCGG had higher PRs with a body condition score (BCS) of 2.5, and the bSTG had a BCS of 3.0 (p < .05). It was concluded that bST increased PR, bST showed better performance in smaller DF and larger follicular diameter on d9 of the protocol, eCG acted better on animals with lower BCSs, and bST can be used in FTAI."

Journal

The Use of Injectable Estradiol in Transgender and Gender Diverse Adults: A Scoping Review of Dose and Serum Estradiol Levels. (PubMed, Endocr Pract) - "Based on the data available, we suggest that clinicians start injectable estradiol valerate via subcutaneous or intramuscular injections at a dose ≤ 5 mg weekly and then titrate accordingly to keep levels within guideline recommended range. Future studies should assess timing of injections and subsequent levels more precisely across the injection cycle and between esters."

Journal • Review

Injectable Estradiol Use In Adult Transgender And Gender Diverse Individuals Throughout The U.S.: A Multisite Retrospective Study (ENDO 2024) - "Introduction: Injectable 17β-estradiol esters (estradiol valerate [EV] and estradiol cypionate [EC]) are commonly prescribed for feminizing therapy in transgender and gender diverse (TGD) persons, but recommendations regarding dosing and frequency of EV/EC injections are based on very little data...We are also evaluating covariates of age, BMI, weight, smoking status, gonadectomy status, anti-androgen and progesterone use, and will include the final site's data. This is the largest multisite collaboration in the US to date evaluating dosing of EV/EC for gender-affirming hormone therapy... This is the largest multisite collaboration in the US to date evaluating dosing of EV/EC for gender-affirming hormone therapy. Our data demonstrate that > 65% of participants had serum E2 levels above target, with the majority > 300 pg/mL. Our data also suggest that target sex hormone levels can be obtained with a median estradiol injection dose of 4 mg q7d regardless of..."

Late-breaking abstract • Retrospective data

Early induction of luteolysis in a timed AI protocol increases reproductive performance in beef cows. (PubMed, Domest Anim Endocrinol) - "On day 0, cows (n = 489) were treated with an intravaginal 1 g progesterone (P4) device and 2 mg of estradiol benzoate. However, in cows with P4 > 2 ng/mL PGF7 cows had higher expression of estrus (89 vs 67.5 %; P = 0.0005) and P/TAI (64.8 vs 48.7 %; P = 0.021) than PGF8. Thus, increasing the proestrous period by inducing luteolysis 24 hours earlier than removing the P4 intravaginal device enhanced fertility in non-suckling cyclic beef cows by increasing expression of estrus and P/TAI."

Journal

The effectiveness of low-dose of eCG in timed AI Nelore (Bos indicus) heifers. (PubMed, Reprod Domest Anim) - "This study evaluated the efficacy of the administration of different doses of equine chorionic gonadotropin (eCG; 0 IU, 200 IU, or 300 IU) at the time of the progesterone device removal in 2-year-old Nelore (Bos indicus) heifers synchronized for fixed-timed artificial insemination (FTAI). Furthermore, eCG treatment increases the diameter of the CL after FTAI and reduces pregnancy losses. No dose effect was observed, suggesting Nelore (Bos indicus) heifers respond to 200 IU of eCG treatment for FTAI."

Journal

Optimizing ReBreed21 I: Evaluation of endocrine and ovarian dynamics in non-bred Bos indicus heifers. (PubMed, Theriogenology) - "A synchronized estrous cycle was induced using a standard timed ovulation protocol (d -10: P4 implant inserted + 2 mg estradiol benzoate; d -2: P4 removed+ 0.5 mg cloprostenol + 0.6 mg estradiol cypionate + 200 IU equine chorionic gonadotropin (eCG); d0: 8.4 μg buserelin) without AI to ensure nonpregnancy in heifers. Synchronized ovulation on day 22-23 was greater (P < 0.01) for ReBreed21 (78.6%; 22/28) and ReBreed21+G (76.9%; 20/26) compared with Control (30.8%; 8/26). Thus, the ReBreed21 resynchronization program produced acceptable endocrine and follicular dynamics, including synchronized ovulation at the end of the protocol in nonpregnant heifers providing good rationale for testing the fertility and practical implementation of this protocol under field conditions."

Journal

Estrogens improve the pregnancy rate in cattle: A review and meta-analysis. (PubMed, Theriogenology) - "The administration of estrogens in the estrus synchronization protocol significantly improved PR in both artificial insemination (OR = 1.2; P = 0.000) and embryo transfer (OR = 1.3; P = 0.033) programs. In summary, incorporating estrogens into estrus induction protocols led to an enhancement of the OR of PR among cattle."

Journal • Retrospective data • Review

The Discovery of inhibitors of the SARS-CoV-2 S protein through computational drug repurposing. (PubMed, Comput Biol Med) - "The results identified estradiol cypionate and telmisartan as inhibitors of SARS-CoV-2 entry into cells. Our findings demonstrate that the methodology presented here enables the discovery of inhibitors targeting viruses for which high-resolution structures are available."

Journal • Infectious Disease • Novel Coronavirus Disease • Respiratory Diseases