Non-hormonal methods of contraception Revision Notes | GCSE OCR Foundation Biology

What this lesson covers

Exploring barrier methods, intrauterine devices, spermicidal agents, natural family planning through abstinence timing, and surgical sterilisation metho...

• Describe the different types of non-hormonal contraceptive methods and how they work
• Explain how barrier methods prevent fertilisation
• Compare the effectiveness and mechanisms of different contraceptive approaches
• Evaluate the advantages and disadvantages of surgical sterilisation methods

Key ideas to keep in view

Use this lesson to stay inside B3.2 Coordination and control - the endocrine system while connecting the detail back to the wider B3: Organism level systems topic.

• B3: Organism level systems
• B3.2 Coordination and control - the endocrine system
• GCSE OCR Foundation Biology

Lesson notes preview

Read the core explanations from Non-hormonal methods of contraception before testing yourself from memory.

• Not everyone can or wants to use hormonal contraception. Some people experience side effects from synthetic hormones, others have medical conditions that make hormones risky, and some prefer methods that don't alter their natural hormone cycles.
• Non-hormonal methods work by physically preventing fertilisation or implantation. They target different stages of reproduction - from stopping sperm reaching the egg, to preventing a fertilised embryo from implanting in the uterus wall.
• Thin latex or polyurethane sheaths that cover the penis (male condoms) or line the vagina (female condoms) to prevent sperm entering the reproductive tract.
• Condoms work by creating a physical barrier. When worn correctly, they collect semen and prevent sperm from swimming up through the cervix into the uterus and fallopian tubes where fertilisation occurs.
• A dome-shaped rubber cup that covers the cervix to block sperm from entering the uterus, usually used with spermicide.
• The diaphragm sits over the cervix like a cap. It must be fitted by a healthcare professional to ensure the correct size. **Trap**: Many students think the diaphragm goes in the uterus - it actually covers the cervix opening.
• Chemical agents containing nonoxynol-9 or other compounds that kill or disable sperm, preventing them from swimming to fertilise an egg.
• Spermicides work by damaging sperm cell membranes or reducing their motility. They're often used alongside barrier methods like diaphragms to increase effectiveness. The chemicals create a hostile environment for sperm in the vagina.
• A T-shaped device inserted into the uterus that prevents implantation of embryos. Copper IUDs release copper ions toxic to sperm and eggs.
• The copper IUD has two mechanisms. First, copper ions are toxic to both sperm and eggs, reducing the chance of fertilisation. Second, if fertilisation does occur, the IUD prevents the embryo from implanting in the uterine wall.

Continue through the topic

Move to the related lessons or back to the topic page when you need the wider sequence before exam-style practice.