Effects of Oral Contraceptives on DNIC in Non-painful Healthy Women

Study Overview
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Brief Summary
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The purpose of this study is tu assess the influence of oral contraceptives (OC) on diffuse noxious inhibitory control (DNIC) in healthy women, tested during high, low endogenous estrogens sessions and ovulatory period.

Detailed Description
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After being informed about the study and it protocol, all patients giving written informed consent, will undergo to a cephalic (masseter) and extracephalic (finger) mechanical stimulus to evaluate the threshold of mechanical pain, and physiological records of systolic/diastolic pressure and heart rates. After, we will evaluate the threshold response and physiological rates to the same mechanical stimulus under a thermal (cold) conditional pain (TCP) at 3 different moments of menstrual period in No contraceptive group (No OC) versus Contraceptive group (CO). Finally, we will compare the mechanical threshold response, physiological rates and pain perception between both groups.

Official Title
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Effects of Oral Contraceptives on Diffuse Noxious Inhibitory Stimulus (DNIC) in Non-painful Healthy Women

Conditions
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Contraceptive Usage, Diffuse Noxious Inhibitory Control

Intervention / Treatment
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* Device: Mechanical stimulus
* Procedure: Thermal (cold) stimulus
* Other: Oral contraceptive (OC)
* Other: No oral contraceptive (No OC)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Healthy women with oral contraceptive treatment (for at least 3 consecutive months), greater than or equal to 15 years old. Healthy women without oral contraceptive treatment, greater than or equal to 15 years old. Non pregnant women. Not under convulsive, chronic pain, antidepresive, antihypertensive, pharmacological treatments Without systemic pathologies. Exclusion Criteria: Treatment of a pain, depression, hypertension, convulsion condition with or without medication. Regular use of benzodiazepines. Systemic pathologies Pregnant women Menopausal women

Ages Eligible for Study
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Minimum Age: 15 Years
Maximum Age: 45 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Health Services Research
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Oral contraceptive (OC)<br>Oral contraceptive patients will be tested to mechanical (cephalic and extracephalic) stimulus and cold pain stimulus. | Device: Mechanical stimulus<br>* Electrical dynamometer to measure mechanical pressure<br>Procedure: Thermal (cold) stimulus<br>* Water cold bath<br>Other: Oral contraceptive (OC)<br>* Oral contraceptive (OC)<br>|
| Experimental: No oral contraceptive (No OC)<br>No oral contraceptive patients will be tested to mechanical (cephalic and extracephalic) stimulus and cold pain stimulus. | Device: Mechanical stimulus<br>* Electrical dynamometer to measure mechanical pressure<br>Procedure: Thermal (cold) stimulus<br>* Water cold bath<br>Other: No oral contraceptive (No OC)<br>* No oral contraceptive (No OC)<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Diffuse Noxious Inhibitory Control Efficiency in oral contraceptive healthy women | The efficiency of diffuse noxious inhibitory control (DNIC) is a measure of one's ability to inhibit pain perception. DNIC efficiency is assessed by a psychophysical test that involves a mechanical pressure in the masseter (cephalic) and finger (extracephalic) stimulus as the test stimulus and a cold-water bath as the conditioning stimulus. The results of this test will be used as the primary outcome measure. | Baseline phase 1 (2-5 days), phase 2 (14-17 days), and phase 3 (21-27 days) after the beginning of menstrual period |