The purpose of this research is to study the effects of 12 weeks of melatonin supplementation compared to placebo in women who are in the menopause transition (perimenopause) and have high blood pressure.

Inclusion Criteria

• Age 40-55 years old

• Female individuals with intact uterus and at least one ovary

• Hypertension

  o Defined as a prior diagnosis of hypertension, use of antihypertensive agents, or office SBP/DBP ≥130/80 mmHg

• On stable medical regimen (≥ 2 months) if taking other medications

Exclusion Criteria

• Prescription sleeping medications or melatonin supplementation
• Pregnant or lactating
• Use of tobacco, nicotine or vaping products
• Night shift work
• On prescription aspirin
• Severe lactose intolerance
• History of substance use disorder
• History of suicidal ideation
• History of clinically diagnosed anemia (within the past 5 years) or low hemoglobin levels (<11.6 g/dL) within the past 12 months
• Active cancer
• Severe daytime sleepiness (score >15 at the Epworth Sleepiness Scale [ESS])81
• Current or recent (within the past 2 months) participation in other research studies at the discretion of study investigators
• Inability to provide written consent and/or to speak and read English
• Any other medical, geographic, or social factor making study participation impractical