With over 15 different contraceptive methods available in the UK, choosing the right one can feel overwhelming. The best option depends on your age, health history, lifestyle, whether you want pregnancy protection for months or years, and whether you can use oestrogen. This guide explains every main method — how it works, how effective it is, and who it suits — to help you make an informed decision with a healthcare professional.

Understanding Contraceptive Effectiveness

All contraceptive effectiveness figures are typically expressed as the number of people per 100 who would become pregnant in one year. Two measures are used:

• Perfect use: Effectiveness when used correctly and consistently every time
• Typical use: Effectiveness in real-world conditions, accounting for human error (missed pills, incorrect application, etc.)

Long-acting reversible contraceptives (LARCs) — the implant, IUS, IUD, and injection — have the highest typical use effectiveness because they remove the scope for user error entirely.

Comparison of All UK Contraceptive Methods

Hormonal Contraceptive Pills

The Combined Oral Contraceptive (COCP)

The combined pill contains synthetic versions of both oestrogen and progestogen. It prevents pregnancy primarily by suppressing ovulation. It also thickens cervical mucus and thins the womb lining. Taken daily for 21 days followed by a 7-day break (or in other regimens), it offers highly effective protection when used consistently.

Key advantages: Can improve period pain, reduce heavy bleeding, and benefit acne in some women. Fully reversible — fertility typically returns within 1–3 months of stopping.

Not suitable for: Women with a history of blood clots (DVT or PE), certain migraines with aura, uncontrolled high blood pressure, breast cancer history, or those who smoke and are aged over 35. All these factors require individual clinical assessment.

The Progestogen-Only Pill (POP / Mini Pill)

The mini pill contains only progestogen — no oestrogen — making it suitable for women who cannot or prefer not to take oestrogen. Desogestrel-based pills (Cerazette, Zelleta) work primarily by suppressing ovulation and are effective across a 12-hour window for missed doses. Older POPs (norethisterone-based) have a narrower 3-hour window and work mainly by thickening cervical mucus.

Suitable for: Breastfeeding women, women over 35 who smoke, those with a history of blood clots, and women for whom oestrogen is contraindicated. See our detailed guide to Zelleta mini pill.

Long-Acting Reversible Contraceptives (LARCs)

Contraceptive Implant (Nexplanon)

A small, flexible rod inserted under the skin of the upper arm by a trained clinician. It releases etonogestrel (a progestogen) continuously, suppressing ovulation. Effective for 3 years with a failure rate of less than 1 in 1,000 users. Fertility returns rapidly after removal. Suitable for women who cannot take oestrogen.

Intrauterine System (IUS — Mirena, Levosert)

A small T-shaped plastic device fitted inside the uterus that releases a low dose of levonorgestrel (progestogen) locally. Effective for 5–8 years depending on the device. Often significantly reduces or stops periods — many women find this a key benefit. Does not contain oestrogen.

Intrauterine Device (IUD — Copper Coil)

A small copper T-shaped device fitted inside the uterus. It contains no hormones — copper ions have a spermicidal effect and make the uterine environment hostile to fertilisation. Effective for 5–10 years. Can also be used as emergency contraception if fitted within 5 days of unprotected sex (the most effective form of post-coital contraception).

Contraceptive Injection (Depo-Provera / Sayana Press)

An injection of medroxyprogesterone acetate (a progestogen) given every 12–13 weeks. No oestrogen. Highly effective but important considerations: fertility can take 6–12 months to return after stopping, and it is not recommended for long-term use in young women due to effects on bone mineral density (bones typically recover after stopping).

Barrier Methods

Condoms are the only contraceptive method that also protects against sexually transmitted infections (STIs). For this reason, NHS and BASHH guidance recommends using condoms in combination with another contraceptive method (“dual protection”) in new or non-monogamous relationships, particularly for those under 25.

Diaphragms and cervical caps must be used with spermicide and fitted by a healthcare professional for correct sizing. They are reusable with proper care.

Emergency Contraception

Emergency contraception should be used as soon as possible after unprotected sex. Options available in the UK:

• Levonorgestrel (Levonelle 1500mcg): Up to 72 hours (3 days) after unprotected sex; most effective the sooner it is taken
• Ulipristal acetate (ellaOne 30mg): Up to 120 hours (5 days) after unprotected sex; maintains effectiveness across the full 5-day window
• Copper IUD: Up to 5 days after unprotected sex; the most effective emergency contraception option (>99%), and provides ongoing long-term contraception