---
title: "Hormones in the Menstrual Cycle and Fertility"
description: "Four hormones run the monthly cycle: FSH and LH from the pituitary, oestrogen and progesterone from the ovaries. The same loop explains how hormonal contraception and fertility treatment work."
canonical: https://lightmysky.com/learn/science/hormones-in-the-menstrual-cycle-and-fertility-mt_DENo5Fbr1d
source: https://lightmysky.com/learn/science/hormones-in-the-menstrual-cycle-and-fertility-mt_DENo5Fbr1d.md
retrieved: 2026-09-12
---

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# Hormones in the Menstrual Cycle and Fertility

Four hormones run the monthly cycle: FSH and LH from the pituitary, oestrogen and progesterone from the ovaries. The same loop explains how hormonal contraception and fertility treatment work.

Subject: Science · Area: The Human Body · Ages 14 to 16
Page: https://lightmysky.com/learn/science/hormones-in-the-menstrual-cycle-and-fertility-mt_DENo5Fbr1d

## Ready when they can

- Places each of the four hormones on a cycle diagram and states what it triggers.
- Explains how keeping oestrogen high stops an egg being released.
- Explains what fertility treatment adds and why it can lead to more than one embryo.

## Lesson: Four hormones, one cycle

Just as insulin and glucagon hold sugar steady, four hormones run the monthly cycle from two control rooms. The pituitary in the brain releases FSH and LH, while the ovaries release oestrogen and progesterone. Each has its own job on the cycle diagram, so place each one before you explain it.

**Example.** Follow the month in order. FSH grows the follicle holding the egg, and the growing follicle makes oestrogen. Rising oestrogen builds the uterus lining and triggers a surge of LH, and that surge releases the egg. The leftover follicle then makes progesterone, which keeps the lining ready.

The same loop explains contraception and fertility treatment. Holding oestrogen high all month stops the LH surge, so no egg is released. Fertility treatment adds extra hormones to grow more follicles, which is why it can lead to more than one embryo.

If no pregnancy happens, progesterone and oestrogen fall and the lining breaks down as a period. Then FSH rises again and the whole cycle restarts from the top.

**Recap.** FSH grows, oestrogen builds and triggers, LH releases, and progesterone keeps the lining ready.

## Practice

8 questions on this page, each with its working shown.

## Needs first

- [Blood Glucose Control and Diabetes](https://lightmysky.com/learn/science/blood-glucose-control-and-diabetes-mt_eOzNtiBvX2)
- [Human Reproduction](https://lightmysky.com/learn/science/human-reproduction-mt_tQkCzRcWG7)

## Opens up

- [Meiosis and Why Gametes Are Haploid](https://lightmysky.com/learn/science/meiosis-and-why-gametes-are-haploid-mt_hvu0bczcfX)