Patient case (clinical description): A 32-year-old woman comes to the hospital with vaginal spotting.  Her last menstrual period was 10 weeks ago. She has regular menses lasting for 6 days and repeating every 29 days. Medical history is significant for appendectomy and several complicated UTIs. She has multiple male partners, and she is inconsistent with using barrier contraceptives. Vital signs are normal.  Serum β-hCG level is 1800 mIU/mL, and a repeat level after 2 days shows an abnormal rise to 2100 mIU/mL.  Pelvic ultrasound reveals a thin endometrium with no gestational sac in the uterus.

Patient's own account: I just turned 32 and last morning I woke up with strange blood stains on my underwear. My last periods were more than 2 months ago, which is unusual for me because I used to have regular periods lasting for 6 days every 29 days, more or less. I had several UTIs in the past. I also had appendicitis. I'm currently seeing several men and, to be honest, some of them do struggle to wear a condom. I went to the hospital to check myself up and they told me that my vitals were normal. I also had a blood test on Monday, and my β-hCG level was 1800 mIU/mL, and then on Wednesday, it went up to 2100 mIU/mL. The gynecologist also did an ultrasound and she told me that, hopefully, there was no ovule.

Clinical trial: CaREFREE Study (Calorie Restriction, Environment and Fitness: Reproductive Effects Evaluation Study)

Eligibility criteria:
-  INCLUSION CRITERIA:

               1. Female

               2. Between 18 and 28 years of age (inclusive)

               3. Reported menarche between the ages of 11 and 14 years

               4. Gynecological age of less than or equal to 14 years

               5. A history of self-reported regular menstrual cycles when not on contraceptive
                  medication of between 25 and 35 days (inclusive) at prescreen and knowledge of
                  date of onset of menses before the screening visit

               6. A BMI of 18.5 to 27 kg (Summation)m(2) and a weight >= 93 lbs.

               7. Agrees to use barrier contraception method for the duration of the study

               8. Agrees to abstain from alcohol consumption during both 5-day diet/exercise study
                  interventions

               9. Agrees to abstain from donating blood during the study and within 30 days of
                  completing the study

              10. Is willing and able to fulfill the requirements of the protocol and to provide
                  informed consent

              11. Able to speak and read English

              12. Lives within 50 miles of the Clinical Research Unit

        EXCLUSION CRITERIA:

          1. Currently lactating or pregnant or planning on becoming pregnant for the duration of
             the study

          2. Has ever given birth

          3. History in the past 3 months of dieting or weight loss amounting to greater than 2 kg
             (4.4 lbs)

          4. > 4 hours per week of aerobic exercise for the past 3 months

          5. Has initiated training for an athletic sport or event in the past 3 months that, in
             the opinion of the investigator, may interfere with the results of the study

          6. Currently using hormone-based contraception, including those administered orally,
             vaginally, via injection, sub-dermally, or transdermally

          7. Current use of medications or supplements that may interfere with the results of the
             study, including:

             i.Steroids

             ii.Hormone-based contraception

             iii.Sleeping pills

             iv.Homeopathic substances (e.g. Chinese herbs, protein or other powders, and
             other-the-counter extracts)

             v.Stimulants (e.g. Ritalin)

             vi.Antidepressants or anti-epileptic medications or centrally acting anti-hypertensive
             medications

          8. Current use of recreational drugs (alcohol intake will be monitored and excluded
             during the two intervention periods)

          9. Unable to consume food containing dairy or nuts

         10. Has currently or has a history of any of the following: autoimmune, heart, liver,
             renal disease, diabetes, or another health condition deemed by the PI to be a
             contraindication to study participation. History of thyroid disorder is permissible if
             the patient is biochemically euthyroid on replacement.

        Additional Eligibility Criteria to be Met Prior to Start of Intervention(s):

        Criteria 1 Habitual energy intake between 35-55 kcal/kg LBM*day

        Criteria 2 VO2max less than or equal to 40 ml/kg/min with the option to increase this at
        the discretion of the PI, depending on the current and past exercise level of the
        participant

        Criteria 3 Hemoglobin, prolactin and TSH within normal female range for testing laboratory.

        Criteria 4 Ovulation confirmed in the cycle before each study intervention by self-reported
        positive urine test, ultrasound and/or progesterone blood-levels
Female
Accepts Healthy Volunteers
Subject must be at least 18 Years old.
Subject must be at most 28 Years

Eligibility (NLI label): Contradiction