Summary
A roughly 28-day cycle in which the uterine lining builds and sheds in response to hormones.
In depth
Follicular phase (days 1 to 14): FSH grows follicles, oestrogen rises and thickens endometrium. Ovulation (about day 14): LH surge. Luteal phase: corpus luteum secretes progesterone. Without pregnancy, hormones fall and the endometrium is shed.
The cycle averages 28 days but varies. Oestrogen rebuilds the endometrium; progesterone maintains it. Menstruation is shedding of the lining.
Key idea: hormones from pituitary and ovary interact by feedback.
The menstrual cycle lasts about 28 days (21 to 35 is normal) and prepares the uterus for pregnancy. Day 1 is the start of menstruation (about days 1 to 5), when the endometrium is shed. In the follicular phase, FSH stimulates follicles and rising oestrogen rebuilds the lining.
Around day 14, an LH surge triggers ovulation. In the luteal phase, the empty follicle becomes the corpus luteum, secreting progesterone which maintains the thick, vascular lining. If no embryo implants, the corpus luteum degenerates, progesterone falls and menstruation begins.
Example: if fertilisation occurs, hCG sustains the corpus luteum.
Remember: the cycle is controlled by feedback between the brain, pituitary and ovaries.
Frequently asked questions
What is Menstrual Cycle?
A roughly 28-day cycle in which the uterine lining builds and sheds in response to hormones.
Which area of biology covers Menstrual Cycle, and how advanced is it?
Menstrual Cycle is one of the 54 topics in Reproduction & Endocrinology. It is rated Beginner, so it suits learners who are starting out in biology. Related topics in this area include Hormonal Control of the Menstrual Cycle, Implantation, Female Reproductive System.
Can you give an example of Menstrual Cycle?
Ovulation can be predicted using LH tests.
What should I learn before Menstrual Cycle?
Menstrual Cycle is a Beginner topic, so no earlier topic is required. Other Beginner topics in Reproduction & Endocrinology that pair well with it include Reproduction, Asexual Reproduction, Sexual Reproduction.
What topics are related to Menstrual Cycle?
The closest topics to Menstrual Cycle are Hormonal Control of the Menstrual Cycle, Implantation, Female Reproductive System, Ovulation. Comparing them side by side is a good way to see how the ideas connect.
How can I check that I understand Menstrual Cycle?
Read the summary and the in-depth section, then use the quick check on the interactive lesson for Menstrual Cycle. To practise the whole of Reproduction & Endocrinology, use the Reproduction & Endocrinology quiz.
How is Menstrual Cycle different from Hormonal Control of the Menstrual Cycle?
Menstrual Cycle: A roughly 28-day cycle in which the uterine lining builds and sheds in response to hormones. Hormonal Control of the Menstrual Cycle: FSH, LH, oestrogen and progesterone interact in feedback loops to time ovulation and menstruation. Read both side by side and note what each one explains.
How should I study Menstrual Cycle step by step?
First, read the summary and write the definition in your own words. Second, read the in-depth section and note any example. Third, compare it with Hormonal Control of the Menstrual Cycle and explain the difference aloud. Finally, take the Reproduction & Endocrinology quiz and come back to this page for any question you miss.