Effects of a Modest Energy Deficit on Reproductive Hormones Across the Menstrual Cycle in Contraceptive Users
试验速览
- 阶段
- 不适用
- 状态
- 尚未招募
- 入组人数
- 30
- 试验地点
- 1
- 主要终点
- Urinary hormone exposure
研究概览
简要总结
The purpose of the present study is to characterize the endocrine and metabolic responses to a modest, short-term energy deficiency (~250 kcal/day) across the menstrual cycle in recreationally active women using different contraceptive methods (oral contraceptive, hormonal IUD, and non-hormonal IUD). This study will leverage daily urinary hormone metabolite tracking and comprehensive metabolic assessments, providing foundational data addressing an important and previously unexamined interaction between energy availability and hormonal regulation in contraceptive users.
详细描述
The purpose of the present study is to characterize the endocrine and metabolic responses to a modest, short-term energy deficiency (~250 kcal/day) across the menstrual cycle in recreationally active women using different contraceptive methods. The investigators will be focusing on oral contraceptive users, hormonal IUD, and non-hormonal (i.e., copper IUD). Daily urinary hormone metabolite tracking and comprehensive metabolic assessments (i.e., resting metabolic rate, body composition via DXA, exercise logs, and energy intake) will be used to provide foundational data addressing an important and previously unexamined interaction between energy availability and hormonal regulation in contraceptive users.
Based on evidence that female reproductive hormones are sensitive to energetic stress, that estrogen plays a central role in regulating metabolism and endocrine function, and that hormonal contraceptive methods differentially alter endogenous hormone profiles, the central hypothesis of this study is that a modest, controlled energy deficiency (~250 kcal/day) will alter reproductive hormone profiles across the menstrual cycle in recreationally active women using contraceptives. Specifically, it is hypothesized that changes in urinary reproductive hormone measures will be detectable during an energy-deficient cycle compared to a baseline cycle, and that the magnitude and pattern of these changes will differ by contraceptive type, with hormonal oral contraceptive users demonstrating a different hormonal response to energy deficiency than copper or hormonal intrauterine device users.
A secondary hypothesis is that energy deficiency-induced hormonal changes will be associated with alterations in resting metabolic rate and body composition, and that these associations may be moderated by exercise energy expenditure and perceived stress. Collectively, these hypotheses are grounded in prior research demonstrating hormonal sensitivity to energetic perturbations and the distinct endocrine environments created by different contraceptive methods, while addressing a clear gap in the current literature regarding the interaction between energy availability and hormonal regulation in contraceptive users.
研究设计
- 研究类型
- Interventional
- 分配方式
- Non Randomized
- 干预模型
- Parallel
- 主要目的
- Screening
- 盲法
- None
入排标准
- 年龄范围
- 18 Years 至 35 Years（Adult）
- 性别
- Female
- 接受健康志愿者
- 否
入选标准
- •Female, aged 18-35 years
- •Recreationally active (engaging in structured exercise between 8-15 hours per week)
- •BMI of 18.5-29.9 as a BMI below or above these cut points results in highly varied menstrual cycle lengths17
- •Not currently experiencing an eating disorder or disordered eating, or having a diagnosed eating disorder in the last 3 years
- •Non-pregnant or planning to become pregnant
- •Medically free from chronic diseases
- •Currently using one of the following contraceptive methods for ≥3 months:
- •Monophasic oral contraceptive
- •Hormonal intrauterine device (H-IUD)
- •Copper intrauterine device
- •Weight stable (no weight change >5% body weight within the past 3 months)
- •Weight greater than or equal to 110 lbs
- •Not suffering from known gynecological disease (i.e., PCOS, endometriosis, etc.) that may influence menstrual cycle regularity
- •Willing and able to maintain current exercise habits throughout the study
- •Willing to follow study dietary guidance to achieve a ~250 kcal/day energy deficit during Cycle 2
排除标准
- •Amenorrhea or oligomenorrhea
- •Perimenopausal or menopausal
- •Currently pregnant, planning pregnancy, or breastfeeding
- •Use of hormonal contraception other than monophasic oral contraceptives or hormonal IUD (implant, nuvaring, etc.)
- •Initiation or change of contraceptive method within the past 3 months
- •Diagnosis of polycystic ovary syndrome (PCOS), endometriosis, hypothalamic amenorrhea, or other known reproductive endocrine disorder
- •Current or history of eating disorder or clinically diagnosed disordered eating
- •Current participation in intentional weight loss or weight gain program
- •Use of medications known to affect metabolism or hormone levels (e.g., systemic corticosteroids, thyroid medications, insulin, GLP-1 agonists)
- •Known metabolic, cardiovascular, renal, hepatic, or endocrine disease
- •Musculoskeletal injury limiting exercise participation within the past 3 months
- •Smoking or nicotine use
- •Contraindications to DXA scanning (e.g., pregnancy, recent high-radiation diagnostic imaging exceeding institutional limits)
- •Inability or unwillingness to comply with study procedures
研究组 & 干预措施
Monophasic low dose oral contraceptive users
The first group will be only individuals who are on a low dose, monophasic oral contraceptive that they have elected to be on prior to enrollment in the study. They will undergo a baseline monitoring menstrual cycle that will include daily urinary hormone monitoring, baseline metabolic and body composition assessments, and assessment of baseline energy expenditure and energy intake. During a two week washout week, participants will not be monitoring hormones, but will be subjected to a ~250 kcal/day energy deficit. Following this imposed energy deficiency, they will resume urinary metabolite testing and exercise intake and expenditure tracking. They will undergo this monitoring for a final menstrual cycle and metabolic and body composition assessments, and assessment of energy expenditure and energy intake.
干预措施: Energy Deficiency of approximately ~250 kcal/day (Behavioral)
Hormonal IUD
The second group will be only individuals who have a hormonal IUD that they have elected to be on prior to enrollment in the study. They will undergo a baseline monitoring menstrual cycle that will include daily urinary hormone monitoring, baseline metabolic and body composition assessments, and assessment of baseline energy expenditure and energy intake. During a two week washout week, participants will not be monitoring hormones, but will be subjected to a ~250 kcal/day energy deficit. Following this imposed energy deficiency, they will resume urinary metabolite testing and exercise intake and expenditure tracking. They will undergo this monitoring for a final menstrual cycle and metabolic and body composition assessments, and assessment of energy expenditure and energy intake.
干预措施: Energy Deficiency of approximately ~250 kcal/day (Behavioral)
Non-Hormonal (i.e., Copper) IUD
The last group will be only individuals who have a non-hormonal/copper IUD that they have elected to be on prior to enrollment in the study. They will undergo a baseline monitoring menstrual cycle that will include daily urinary hormone monitoring, baseline metabolic and body composition assessments, and assessment of baseline energy expenditure and energy intake. During a two week washout week, participants will not be monitoring hormones, but will be subjected to a ~250 kcal/day energy deficit. Following this imposed energy deficiency, they will resume urinary metabolite testing and exercise intake and expenditure tracking. They will undergo this monitoring for a final menstrual cycle and metabolic and body composition assessments, and assessment of energy expenditure and energy intake
干预措施: Energy Deficiency of approximately ~250 kcal/day (Behavioral)
结局指标
主要结局
Urinary hormone exposure
时间窗: From enrollment to energy deficit menstrual cycle is 3 months/90 days
Participants will be asked to track daily urine concentrations of estrogen and progesterone throughout a baseline (i.e., non-energy-deficient state) menstrual cycle and a menstrual cycle with an imposed energy deficit. The outcome will compare hormone exposure measured by the urinary concentrations between the two cycles.
次要结局
- Estimated versus actual resting metabolic rate(From enrollment to completion 90 days/3 months)
- Eating behaviors and attitudes will be measured using the EDEQ and the Three Factor Eating Questionnaire(From enrollment to conclusion 90 days/3 months)
- Subjective stress levels will measured using the Perceived Stress Scale(From enrollment to conclusion 90 days/3 months)
- Low Energy Availability Indicators will be assessed using the LEAF-Q(From enrollment to conclusion 90 days/3 months)
- Body composition will be measured using DXA(From enrollment to conclusion 90 days/3 months)
研究者
Todd Schroeder
PhD
University of Southern California