This key facts covers The 28-Day Menstrual Cycle within Contraception for GCSE Biology. Topic 9: Contraception It is section 2 of 12 in this topic. Use this key facts to connect the idea to the wider topic before moving on to questions and flashcards.
Topic position
Section 2 of 12
Practice
15 questions
Recall
20 flashcards
📌 The 28-Day Menstrual Cycle
- Days 1-5: Menstruation — uterus lining breaks down (period)
- Days 6-13: Uterus lining rebuilds; egg matures (FSH + oestrogen)
- Day 14: Ovulation — egg released (LH surge)
- Days 15-28: Uterus lining maintained by progesterone
- If no fertilisation, progesterone drops and cycle restarts
📊 Visual: The Menstrual Cycle
📌 Remember: FSH → egg matures | Oestrogen → repairs lining, triggers LH | LH → ovulation (day 14) | Progesterone → maintains lining