Terms used to describe menstruation
Menstrual Cycle
Related terms · Menstrual cycle · Menstrual interval
The menstrual cycle is the period from the first day of one menstruation to the day before the next menstruation begins.
Reviewed by Korean Medicine Doctor Choi Yeon-seung · Last updated 2026-08-25
Meaning and Distinctions
What is the menstrual cycle?
We look not only at the cycle interval but also at the number of days bleeding lasted, whether the amount was more or less than usual, pain and blood clots, and the point at which it changed from previous cycles. The menstrual cycle is the period from the first day of one menstruation until the day before the next menstruation begins.
- Easily confused terms
- Calendar dates alone ovulation cannot determine the status or health condition.
- Why this is checked during medical evaluation
- It is the starting point for determining the cause of cycle changes and the timing for medical evaluation.
- What to record for your visit
- Please record the start and end dates of your last three cycles, the number of pad or tampon changes to estimate blood loss, any pain and medications taken, and anything that differs from your usual pattern.
Women's Health Glossary
Compare similar terms here
You can check a brief definition before proceeding to a detailed explanation.Abnormal Uterine BleedingAbnormal uterine bleeding is a broad term for bleeding where the timing, amount, or duration of menstruation differs from your usual pattern.AmenorrheaAmenorrhea is a state where menstruation has not started or where previous menstruation has stopped for a certain period.DysmenorrheaDysmenorrhea is pain in the lower abdomen and lower back that occurs before and after menstruation; it is categorized into primary pain and secondary pain caused by other medical conditions.
Read More
Check guides where this term is used
- Condition GuideIrregular MenstruationThere is more than one cause of irregular menstruation. First, the possibility of pregnancy is checked, followed by polycystic ovary syndrome (PCOS) causing irregular ovulation, thyroid issues, significant weight changes, excessive exercise, stress, hormonal contraceptives, and changes during puberty or the menopausal transition. If the possibility of pregnancy coincides with one-sided pelvic pain, bleeding, or dizziness, or if heavy bleeding causes shortness of breath or a feeling of fainting, an immediate visit to an OB/GYN or emergency evaluation takes priority over a consultation regarding the cause.→
- Condition GuideAmenorrheaThe first cause to check for amenorrhea is pregnancy. If not pregnant, causes may include physiological changes such as breastfeeding or menopause, rapid weight loss, insufficient energy intake, excessive exercise, stress, polycystic ovary syndrome, thyroid/hypothalamus/pituitary issues, primary ovarian insufficiency, hormonal contraceptives, or other medications. If the first period has not started, delayed puberty, genetic/chromosomal conditions, and differences in uterine or vaginal development are also checked. Rather than attributing the cause to weight or stress alone, it is differentiated through pregnancy tests, medical history, physical examination, and necessary hormone tests or ultrasounds.→
- Medical Evaluation GuideWhat should I check first when menstrual pain and bleeding change?First, check if the pain is more severe than usual, if bleeding has increased or occurred between periods, or if there is a possibility of pregnancy. If you experience bleeding that requires changing menstrual products every hour, dizziness as if you might faint, shortness of breath, or if you have one-sided pelvic pain, shoulder pain, and bleeding along with a possibility of pregnancy, you must be evaluated immediately without waiting for your next appointment. If it is not an urgent situation, please record not only the pain level but also any preceding changes, such as a feeling of blockage in the solar plexus, constipation, or cravings for sweets before menstruation, to help narrow down the treatment questions more quickly.→
- Women's Health ColumnMenstrual calendar: Besides the start date, what else should I track to help with treatment?→
Evidence and Update Information
The following materials were referenced to verify the basis and scope of the definitions and treatment explanations.