Study, 1989
How does prolactin change during a full day and night across the menstrual cycle?
Prolactin goes up and down in irregular episodes throughout day and night. The pattern of these ups and downs changes depending on time of day and whether someone is asleep or awake.
What they did
Blood samples were drawn frequently over 2-hour periods at different times during day and night in both the first and second halves of the menstrual cycle to measure prolactin.
What they found
Prolactin showed irregular fluctuations throughout the 24-hour day. The pattern of these fluctuations varied depending on what time of day blood was drawn and whether the woman was sleeping or awake.
What it means for you
How much prolactin is released and when it goes up and down depend on time of day and sleep state. This is a small study with limited information on the specific patterns observed.
2-hour periods
blood sampling duration
About the study
- Original title
- Prolactin concentrations during the normal menstrual cycle: rhythms within rhythms
- Authors
- Tennekoon KH, Lenton EA
- Journal
- The Ceylon medical journal
- Year
- 1989
- Study design
- Study
- What was tested
- None (observation only)
- Read the paper
- https://pubmed.ncbi.nlm.nih.gov/2620370/
Topics
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