Recruiting

Observational Study

Sponsor:

University of Delaware

Code:

NCT06745466

Conditions

Estrogen

Premenopause

Eligibility Criteria

Sex: Female

Age: 40 - 55

Healthy Volunteers: Accepted

Interventions

ganirelix acetate

Study Details

Brief summary:

The purpose of this study is to identify the impact of estradiol (E2) on the associations between (a) responsivity to daily stress or (b) sleep variability with vascular function in midlife premenopausal women.

Conditions

Estrogen

Premenopause

Study ID

NCT06745466

Start date

Nov 15, 2024

Status verified date

Apr, 2026

Completion date

Oct, 2027

Anticipated

Primary completion date

Oct 31, 2026

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: Female

Age: 40 - 55

Healthy Volunteers: Accepted

Inclusion Criteria:

  • Female
  • Age 40-55
  • Premenopausal

Exclusion Criteria:

  • Pregnancy (including a positive urine pregnancy test), planning to become pregnant, or breast-feeding
  • Peri- or post-menopausal
  • Unstable or diagnosed chronic clinical disease, including cardiovascular, metabolic, renal, hepatic, autonomic, autoimmune, or dermatological disease
  • Current or lifetime major psychiatric illness (e.g., major depressive disorder, bipolar disorder, schizophrenia, eating disorders)
  • History of hysterectomy (complete or partial), polycystic ovary syndrome, endometrial hyperplasia, irregular menstrual cycles, or endometrial ablation
  • Suspected potential presence of obstructive sleep apnea (STOP-Bang score >3) or insomnia (Insomnia Severity Index score >15)
  • Current or recent (within 8 wks) use of medications that could conceivably alter cardiovascular function or sleep health
  • Changes or alterations in medication status (starting a new, additional, or different medication or changing the dose of a current medication)
  • Body mass index >35 kg/m2
  • Tobacco or nicotine use, including vaping and electronic cigarettes
  • Working night-time or rotating shift work within the previous 3 months
  • Trans-meridian travel during study enrollment (inclusive of the entire duration of enrollment and the period between testing cycles)
  • Known allergies to pharmacological agents/drugs
  • Current use of long-acting reversible contraception (LARC; e.g., IUDs, birth control implants)
  • Known latex allergy

Study Design

Enrollment

30 participants

Anticipated

Allocation

Non randomized

Intervention Model

Single group

Primary purpose

Basic Science

Interventions and Outcome Measures

Arms

no intervention: Natural cycle

Participants will undergo study measurements during the follicular phase of their natural menstrual cycle.

experimental: No to Low Endogenous Estrogen

Participants will undergo study measurements during 10 days of daily ganirelix acetate (Antagon) injections.

Interventions

ganirelix acetate

Ganirelix acetate (Antagon) will be used to prevent endogenous production of ovarian hormones in young women. Ganirelix is derived from native GnRH, and acts by competitively blocking GnRH receptors on the pituitary and subsequent pathways. Thus, administration of the GnRH antagonist (GnRHant) suppresses steroidogenesis, leading to low or undetectable serum estrogen and progesterone concentrations, which occurs within two days of initiation of administration. Women will self-administer subcutaneous injections (0.25 mg/day in 0.5 ml of normal saline) of the GnRH antagonist ganirelix acetate (Antagon, Organon, Inc., West Orange, New Jersey,) every day for \~12-15 days (starting on day \~2-4 of the menstrual cycle). Testing will occur on day 3-4 and day14-15 of using Antagon.

Primary outcome measure

  • Endothelium-dependent dilation (EDD) [ Time Frame: Immediately before and after each 10-day measurement burst ]
  • Negative affective response to daily stressors [ Time Frame: 10-day measurement burst ]
  • Sleep variability [ Time Frame: 10-day measurement burst ]

Central Contacts and Locations

Central contacts

Jody Greaney, PhD

302-831-2193jgreaney@udel.edu

Virginia Nuckols, PhD

gnuckols@udel.edu

Locations

University of Delaware

Recruiting

Newark, Delaware, United States, 19713

Contacts

Jody Greaney, PhD

302-831-2193jgreaney@udel.edu

Virginia Nuckols, PhD

gnuckols@udel.edu

Principal Investigator:

Jody Greaney, PhD

More Information

Sponsor

University of Delaware

Last update posted

Jul 2, 2026

Last verified

Apr, 2026

Keywords

  • Premenopause
  • Estrogen
  • Stress
  • Sleep
  • Vascular function

Trial information was received from ClinicalTrials.gov and was last updated on 2026-10-03. This information was provided to ClinicalTrials.gov by University of Delaware on 2026-07-02. Recruitment status is synced daily from ClinicalTrials.gov and may not reflect the sponsor's current status. Confirm during your call.