Prolactin Release Through Breast Stimulation in Non-lactating Women - Who Does Respond?

NCT ID: NCT05208684

Last Updated: 2024-05-14

Basic Information

• Recruitment Status: RECRUITING
• Clinical Phase: NA
• Total Enrollment: 40 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2022-02-21
• Study Completion Date: 2024-12-31

Brief Summary

Prolactin is a multifunctional hormone which acts in different cell types rather than just modulating reproduction and lactation. One additional point is its action on glucose metabolism which is described especially in rodents. Prolactin affects proliferation, survival and insulin production of pancreatic beta cells in animal models. But also in human studies prolactin is linked to insulin action. Low systemic levels of prolactin are associated with increased prevalence of diabetes and while higher levels are associated with higher insulin sensitivity.

Acute metabolic effects of prolactin in young, healthy and non-lactating women should be accessed. Therefore, the induction of a transient increase of circulating prolactin levels is necessary to study the acute effects of this hormone on metabolic processes. This can most likely be achieved in non-pregnant and non-lactating women without pharmacological intervention.

As the main stimulus of prolactin release from the pituitary gland is the mechanical stimulation of the breast / nipple, like a suckling baby, stimulation by a breast pump might trigger prolactin release.

Due to other studies in this field, only a minority of women respond to breast stimulation with an increase in prolactin levels. Therefore, this pilot study will assess if an electric milk pump can stimulate prolactin release in non-lactating women. The second aim of the study is to identify factors which determine response and non-response to breast stimulation.

Prolactin will be measured in blood serum. The primary objective of this study is to identify women in whom a 30-minute breast stimulation causes a marked prolactin release. Response is defined as an increase at least twice the baseline value.

Second outcomes are the quantification and duration of prolactin increase as well as to detect differences in responders and non-responders. Therefore, demographic data as well as anthropometric data will also be assessed. A 10-minute electrocardiography and non-invasive measurement of resting energy expenditure by indirect calorimetry will also be performed. History of menstrual cycle, intake of contraceptive, parity and lactation experience will be recorded. Physical activity level and feeling of hunger will be assessed by questionnaires.

Feeling of hunger, resting energy expenditure, blood pressure, heart rate and body temperature will be assessed repeatedly to register differences before and after stimulation. Blood and urine samples will be assessed for safety.

Conditions

Prolactin; Breast Stimulation

Study Design

• Allocation Method: NA
• Intervention Model: SINGLE_GROUP
• Primary Study Purpose: OTHER
• Blinding Strategy: NONE

Study Groups

Breast stimulation

A 30-minute stimulation with moderate intensity by an electric milk pump (Elvie Pump) will be performed.

Group Type: EXPERIMENTAL

Breast stimulation

Intervention Type: OTHER

Breast stimulation by the Elvie Pump to trigger prolactin release.

Interventions

Breast stimulation

Breast stimulation by the Elvie Pump to trigger prolactin release.

Intervention Type: OTHER

Eligibility Criteria

Inclusion Criteria

• Women, aged between 18 and 45 years
• premenopausal (women, who had menses at any time in the preceding 24 consecutive months)
• BMI < 25 kg/m²
• Ability to understand and voluntarily sign an informed consent document prior to any study related procedures

Exclusion Criteria

• Type 1 or Type 2 diabetes
• Intake of medication which may affect prolactin levels (e.g. Metoclopramide, Methyldopa, opiates, cimetidine), except birth control pill/hormonal contraception known hyperprolactinemia or hyperthyroidism
• any other serious illness that might impact the results as judged by the investigator (e.g. malignant disease, coronary heart disease)
• Pregnant / breastfeeding women (weaning at least 6 month ago)
• plastic breast surgery (with detachment of milk ducts)
• allergy to BPA-free plastic

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 45 Years
• Eligible Sex: FEMALE
• Accepts Healthy Volunteers: Yes

Sponsors

University Hospital Tuebingen

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Locations

University Hospital Tuebingen, Otfried-Mueller Str. 10

Tübingen, , Germany

Site Status: RECRUITING

Countries

Germany

Central Contacts

Louise Fritsche, Dr.rer.nat.

Role: CONTACT

louise.fritsche@med.uni-tuebingen.de

+4970712780687

Dorina S. Löffler, M. Sc.

Role: CONTACT

dorina.loffler@med.uni-tuebingen.de

+4970712780687

Facility Contacts

Louise Fritsche, Dr.

Role: primary

louise.fritsche@med.uni-tuebingen.de

+49 (0)7071 29 80687

Other Identifiers

PRL Pilot

Identifier Type: -

Identifier Source: org_study_id