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

Estradiol esters are dispensable in progesterone-based TAI protocols for Bos taurus suckling beef cows. (PubMed, Anim Reprod Sci) - "Also, on D0, cows in the Control group received 2 mg of estradiol benzoate IM and cows in the GnRH/GnRH and GnRH/EC groups received 20 µg of buserelin acetate IM. No difference was observed in the estrus rate before TAI (D9; 72.1, 62.4 and 67.9 %; P = 0.22) or in the pregnancy rate (56.9, 53.1 and 53.6 %; P = 0.77) for control (n = 153), GnRH/EC (n = 147) and GnRH/GnRH (n = 155), respectively. In conclusion, estradiol replacement by GnRH in TAI protocols does not affect LF diameter, estrus expression and pregnancy rate in suckling Bos taurus beef cows."

Journal

Estradiol treatment and double dose of GnRH for resynchronization protocols and timed artificial insemination in lactating dairy cows. (PubMed, Theriogenology) - "The aim of this study was to compare pregnancy per AI (P/AI) in resynchronization (Resynch) protocols using different hormonal combinations (estradiol benzoate [EB], a double dose of GnRH, or EB with a double dose of GnRH) administered on the day of progesterone (P4) device insertion...The secondary objective was to compare P/AI in cows treated with two different GnRH agonists (gonadorelin acetate or buserelin acetate) on the day of P4 device insertion...In conclusion, the combined administration of EB and a double dose of GnRH does not improve P/AI compared with the administration of either hormone alone. Furthermore, both agonists produced comparable P/AI, confirming that they are equally effective when administered during P4 device insertion."

Journal

Relationship between anti-Müllerian hormone concentration and antral follicle count in Colombian creole cows of the Chino Santandereano breed. (PubMed, J Adv Vet Anim Res) - "For the synchronization of estrus and ovulation, an intravaginal progesterone release device plus 2 mg of estradiol benzoate was applied for 8 days. The results showed that in Creole cows of the Chino Santandereano breed, there is a high correlation between circulating levels of AMH and ovarian reserve. This mechanism can be used as an endocrine biomarker of the follicular population."

Journal

Effect of EC-GnRH34 timed AI protocol on ovulation synchrony and fertility in crossbred Girolando dairy cows. (PubMed, Trop Anim Health Prod) - "At the IPD removal, all cows were treated with 1 mg i.m estradiol cypionate (EC), and then allocated into two groups to receive either 2.5 mL of saline solution (EC-Control, n = 111) or 10.5 μg i.m. buserelin acetate (GnRH analogue) 34 h after IPD removal (EC-GnRH34, n = 115). In conclusion, the present study demonstrated that the ovulation synchrony is optimized with the use of GnRH 34 h after IPD removal. Fertility to the TAI protocol, however, was not significantly improved in comparison with cows treated with a single ovulation inducer, EC."

Journal

Single-Center Retrospective Analysis of Safety and Efficacy of Subcutaneous Estradiol Use in Transgender and Nonbinary Adolescents and Young Adults. (PubMed, Transgend Health) - "A retrospective single-center chart review of TGNB adolescents and young adults up to 25 years old who received SC estradiol cypionate or SC estradiol valerate and completed laboratory testing between January 1, 2021, and January 1, 2024, was conducted. No clinically significant adverse events occurred, including new transaminase elevation, severe dyslipidemia, or thromboembolism. Many TGNB adolescents and young adults on SC estradiol administration achieved appropriate serum estradiol concentrations and no adverse events were reported, supporting continued use of SC estradiol in gender-affirming care."

Journal • Retrospective data • Cardiovascular • Dyslipidemia • Metabolic Disorders

Integrative genomic and bioinformatic prioritization of drug repurposing candidates for prostate cancer. (PubMed, BMC Pharmacol Toxicol) - "Integrating genomics, bioinformatics, and molecular docking provides an effective strategy for identifying and prioritizing drug repurposing candidates in prostate cancer. Estradiol-benzoate, estradiol-cypionate, and selumetinib emerge as promising candidates, meriting further preclinical and clinical evaluation for advanced prostate cancer therapy."

Journal • Genito-urinary Cancer • Oncology • Prostate Cancer • Solid Tumor • MAP2K1

Cardiovascular risk of gender-affirming estrogen therapy in a transgender rat model. (PubMed, J Mol Med (Berl)) - "Estrogen therapy in transgender female rats compensates ROS and myocardial distensibility. Estrogen therapy in transgender female rats worsens lipid management and cardiac contractility."

Journal • Preclinical • Anesthesia • Cardiovascular • Hypertension

Plasma Estradiol and Endometrial Edema Profile in Acyclic Mares After Single Administration of 17-β Estradiol, Estradiol Benzoate and Estradiol Cypionate. (PubMed, Reprod Domest Anim) - "A correlation between estradiol concentration and endometrial edema was only seen when using EC, and this hormone also produced the most similar concentration values to those found in natural cycling mares. Therefore, it is likely that EC would be a suitable hormone for preparing acyclic mares as embryo recipients."

Journal

Endometrial gene expression of lactating Holstein cows: Impact of pre-estrus progesterone and intensity of estrous expression. (PubMed, J Dairy Sci) - "When estradiol concentrations near the onset of estrus were measured, we found that estradiol modulated endometrial expression of IGF1 and MUC1 genes, but this effect was observed only under the low P4 treatment. In conclusion, our study revealed substantial differences in endometrial gene expression between cows treated with different P4 concentrations during the follicular growth and expressing different intensities of estrus."

Journal • CCL2 • CCL22 • CXCL8 • IGF1 • IGF2 • IL1A • IL1B • MMP1 • MMP3 • MMP9 • MUC1 • NFKB2 • PTX3

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