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AnovulationNCT00260286

Effects of Gynecological Age on LH Sensitivity to Energy Availability

A study testing Energy availability in people with Anovulation and Amenorrhea, run by Ohio University at 1 site in United States.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record
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Trial summary

The purpose of this experiment is to investigate whether the dependence of luteinizing hormone pulsatility on energy availability declines during adolescence. Read more about this study

Who is it for?
Ages 18 to 34 years, women onlyHealthy volunteers can take part
Conditions the study is for
Anovulation, Amenorrhea, Infertility
What is being tested?
Energy availability
How many people
18 participants
Where
1 siteUnited States
Study dates
Aug 2001to May 2004
Phase
Interventional
Are there results?
None posted in the registry

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 18 to 34 years
  • Women only
  • Healthy volunteers accepted
  • Adult

Who may be able to join

  • 5-8 or 14-18 years of gynecological age
  • menstrual cycles of 26 to 32 days for the previous 3 months
  • luteal phase length >11 days
  • 18-32% body fat

Who cannot join

  • smoking
  • oral contraceptives
  • hematocrit <35%
  • diet with <35 or >55 kcal/kgFFM/day of energy
  • habitually performing more than 60 minutes/week of aerobic exercise
  • histories or evidence of heart, liver, or kidney disease, diabetes, menstrual or thyroid disorders, pregnancy, lactation, and congenital or acquired orthopedic abnormalities

Trial locations and contacts

1 site in 1 country.

United States1 site

  • Ohio University

    Athens, Ohio, 45701

Other trials in United States

About this study

Official title: Dietary Energy Requirements in Physically Active Men and Women, Objective 4B: Effects of Gynecological Age on LH Sensitivity to Energy Availability

The purpose of this experiment is to investigate whether the dependence of luteinizing hormone pulsatility on energy availability declines during adolescence.

Read the detailed description

The incidence of menstrual disorders declines during adolescence. This has long been attributed to the gradual "maturation" of the hypothalamic-pituitary-ovarian axis, but the mechanism of this "maturation" is not known. Ovarian function critically depends on the pulsatile secretion of gonadotropin-releasing hormone (GnRH) by the hypothalamus and on the consequent and more readily assessed pulsatility of luteinizing hormone (LH) secretion by the pituitary. LH pulsatility has been shown to depend on energy availability, operationally defined as dietary energy intake minus exercise energy expenditure. The effects of energy availability on LH pulsatility are thought to be mediated by certain metabolic substrates and hormones.

Comparison: By manipulating diet and exercise regimens, contrasting energy availability treatments of 10 and 45 kilocalories per kilogram of fat-free mass per day are being administered to adolescents with 5-8 years of gynecological age and to adults with 14-18 years of gynecological age for five days in the early follicular phase of separate menstrual cycles. Effects of low energy availability on LH pulsatility and on selected metabolic substrates and hormones are being measured.

Being tested
Energy availability
Keywords
LH pulsatility, energy availability, exercise, diet, gynecological age
Medical subject headings
Anovulation, Amenorrhea, Infertility, Starvation, Motor Activity

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • Energy availabilityBehavioural

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Differences in 24h LH pulse frequency, 24h LH pulse amplitude and 24h LH mean concentration in blood samples drawn q10' for 24 hours after 5 days of treatment

Secondary outcomes (1)

  1. Differences in 24h average glucose, beta-hydroxybutyrate, insulin, cortisol, growth hormone, insulin-like growth factor-I, tri-iodothyronine, and leptin concentrations in blood samples drawn q10' for 24 hours after 5 days of treatment

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted1 Dec 2005 (estimated)
  2. Study startAug 2001
  3. Study completionMay 2004

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Interventional
Phase
Phase N/A
Primary purpose
Prevention
Allocation
Randomised
Intervention model
Crossover
Masking
None (open label)
Enrolment
18 participants
IDs, dates and publications
ClinicalTrials.gov ID
NCT00260286
Sponsor's protocol ID
Excalibur X
Other IDs
DAMD_17-95-1-5053,, M01RR000034
Status last verified
Nov 2005
First submitted
30 Nov 2005
Last updated
5 Dec 2005
Results posted
No

Publications

  • Loucks AB, Verdun M, Heath EM. Low energy availability, not stress of exercise, alters LH pulsatility in exercising women. J Appl Physiol (1985). 1998 Jan;84(1):37-46. doi: 10.1152/jappl.1998.84.1.37.

    PubMed 9451615

  • Loucks AB, Heath EM. Induction of low-T3 syndrome in exercising women occurs at a threshold of energy availability. Am J Physiol. 1994 Mar;266(3 Pt 2):R817-23. doi: 10.1152/ajpregu.1994.266.3.R817.

    PubMed 8160876

  • Hilton LK, Loucks AB. Low energy availability, not exercise stress, suppresses the diurnal rhythm of leptin in healthy young women. Am J Physiol Endocrinol Metab. 2000 Jan;278(1):E43-9. doi: 10.1152/ajpendo.2000.278.1.E43.

    PubMed 10644535

  • Loucks AB, Callister R. Induction and prevention of low-T3 syndrome in exercising women. Am J Physiol. 1993 May;264(5 Pt 2):R924-30. doi: 10.1152/ajpregu.1993.264.5.R924.

    PubMed 8498602

  • Loucks AB, Heath EM. Dietary restriction reduces luteinizing hormone (LH) pulse frequency during waking hours and increases LH pulse amplitude during sleep in young menstruating women. J Clin Endocrinol Metab. 1994 Apr;78(4):910-5. doi: 10.1210/jcem.78.4.8157720.

    PubMed 8157720

  • Loucks AB, Verdun M. Slow restoration of LH pulsatility by refeeding in energetically disrupted women. Am J Physiol. 1998 Oct;275(4):R1218-26. doi: 10.1152/ajpregu.1998.275.4.R1218.

    PubMed 9756553

  • Loucks AB, Thuma JR. Luteinizing hormone pulsatility is disrupted at a threshold of energy availability in regularly menstruating women. J Clin Endocrinol Metab. 2003 Jan;88(1):297-311. doi: 10.1210/jc.2002-020369.

    PubMed 12519869

  • Ihle R, Loucks AB. Dose-response relationships between energy availability and bone turnover in young exercising women. J Bone Miner Res. 2004 Aug;19(8):1231-40. doi: 10.1359/JBMR.040410. Epub 2004 Apr 19.

    PubMed 15231009

Questions about this trial

What is this clinical trial studying?

A study testing Energy availability in people with Anovulation and Amenorrhea, run by Ohio University at 1 site in United States.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 4 inclusion and 6 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: finished, as of the sponsor's last update on 5 Dec 2005. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

Are results available for this study?

The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Differences in 24h LH pulse frequency, 24h LH pulse amplitude and 24h LH mean concentration in blood samples drawn q10' for 24 hours after 5 days of treatment. It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT00260286, which also lists 8 linked publications.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 5 Dec 2005.

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