Summary
Release of a secondary oocyte from the ovary triggered by a surge in luteinising hormone.
In depth
The follicle ruptures, releasing the oocyte surrounded by cumulus cells, which is swept into the fallopian tube. The ruptured follicle becomes the corpus luteum. Fertile window is about 5 days.
Ovulation is triggered by the LH surge. Basal body temperature rises after ovulation. The oocyte survives about 24 hours.
Remember: ovulation is mid-cycle in a 28-day cycle.
Ovulation is the release of a secondary oocyte, surrounded by cumulus cells, from a mature (Graafian) follicle. The LH surge triggers enzymes that weaken the follicle wall, causing it to rupture, and the oocyte is swept into the fallopian tube by fimbriae.
It usually occurs around day 14 of a 28-day cycle, and the egg survives 12 to 24 hours, while sperm may survive up to 5 days, so the fertile window is about 6 days. Signs include a rise in basal body temperature after ovulation, clear stretchy cervical mucus and mild pain (mittelschmerz). Irregular ovulation is a main cause of infertility, as in PCOS.
Example: fertility drugs such as clomiphene induce ovulation.
Remember: ovulation does not mean menstruation; it occurs about two weeks earlier.
Frequently asked questions
What is Ovulation?
Release of a secondary oocyte from the ovary triggered by a surge in luteinising hormone.
Which area of biology covers Ovulation, and how advanced is it?
Ovulation is one of the 54 topics in Reproduction & Endocrinology. It is rated Intermediate, so it suits learners who already know the core vocabulary. Related topics in this area include Menstrual Cycle, Hormonal Control of the Menstrual Cycle, Fertilisation Process.
Can you give an example of Ovulation?
Some women feel mittelschmerz pain at ovulation.
What should I learn before Ovulation?
Work through the Beginner topics in Reproduction & Endocrinology first, such as Reproduction, Asexual Reproduction, Sexual Reproduction, then return to Ovulation. Intermediate topics assume the Beginner vocabulary.
What topics are related to Ovulation?
The closest topics to Ovulation are Menstrual Cycle, Hormonal Control of the Menstrual Cycle, Fertilisation Process, Female Reproductive System. Comparing them side by side is a good way to see how the ideas connect.
How can I check that I understand Ovulation?
Read the summary and the in-depth section, then use the quick check on the interactive lesson for Ovulation. To practise the whole of Reproduction & Endocrinology, use the Reproduction & Endocrinology quiz.
How is Ovulation different from Menstrual Cycle?
Ovulation: Release of a secondary oocyte from the ovary triggered by a surge in luteinising hormone. Menstrual Cycle: A roughly 28-day cycle in which the uterine lining builds and sheds in response to hormones. Read both side by side and note what each one explains.
How should I study Ovulation 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 Menstrual Cycle and explain the difference aloud. Finally, take the Reproduction & Endocrinology quiz and come back to this page for any question you miss.