Contraception, compared honestly

Almost every comparison of contraception quotes the perfect-use figure, which describes a version of life nobody lives.

Perfect use and typical use

Perfect use means the method is used correctly and consistently every single time.

Typical use means what actually happens over a year in a real population — pills missed, condoms applied late, appointments postponed.

The gap between the two is small for methods that require nothing of the user and very large for methods that require something daily.

The combined pill is around ninety-nine per cent effective in perfect use and around ninety-one per cent in typical use, which means roughly nine users in a hundred become pregnant in a year.

Condoms are around ninety-eight and eighty-two.

Implants, intrauterine devices and sterilisation are above ninety-nine per cent in both columns, because there is nothing to remember.

Which is the single most important fact in the whole comparison and the one least often stated up front.

The long-acting methods

The implant is a small rod placed under the skin of the upper arm, lasting three years in most licensed products.

The hormonal intrauterine device sits in the uterus and lasts between three and eight years depending on the type; it tends to reduce bleeding substantially and stops periods altogether for a proportion of users.

The copper intrauterine device contains no hormones, lasts up to ten years, and commonly makes periods heavier and more painful, particularly in the first months.

The injection lasts around three months and is the one long-acting method with a delayed return of fertility, which can take up to a year.

Insertion of an intrauterine device is uncomfortable and, for some people, painful; guidance in several countries has recently shifted towards offering better analgesia, and asking about pain relief before the appointment is entirely reasonable.

The short-acting hormonal methods

The combined pill, patch and vaginal ring contain oestrogen and progestogen and share the same contraindications — a history of certain clots, migraine with aura, and some cardiovascular risk factors among them.

The progestogen-only pill has fewer restrictions and is suitable for many people who cannot use oestrogen, including while breastfeeding.

Newer progestogen-only pills have a wider window for a missed dose than the older ones, which matters in practice more than it sounds.

Non-contraceptive benefits are real and worth weighing: reduced bleeding and pain, cycle predictability, acne improvement, and in the case of combined methods a documented reduction in ovarian and endometrial cancer risk.

Barrier and fertility-awareness methods

Condoms are the only method that also reduces transmission of infections, which is why they are frequently used alongside something else rather than instead of it.

Diaphragms and caps require spermicide and correct fitting and have relatively high typical-use failure.

Fertility awareness methods vary enormously in effectiveness depending on the specific method and the training behind it — a well-taught symptothermal method with consistent use performs far better than an app that predicts from calendar data alone, and the marketing around cycle apps has blurred that distinction considerably.

Emergency contraception

Worth knowing before it is needed.

The copper intrauterine device is the most effective emergency option by a wide margin and can be fitted up to five days after the earliest likely ovulation.

Of the pills, ulipristal acetate is effective closer to ovulation than levonorgestrel; both work better the sooner they are taken.

Body weight affects the effectiveness of the oral options, and the interaction between emergency pills and restarting hormonal contraception matters, so pharmacist advice is worth actually taking.

Choosing

The questions that lead to a good decision.

How important is it that pregnancy does not happen this year, honestly?

Will you remember something daily, over years, including on chaotic weeks?

Do you want to keep periods, reduce them, or stop them?

Do you need protection against infection as well?

How soon might you want to conceive?

Are there medical conditions or medications that rule anything out?

And what did you dislike about anything you have tried before, which is frequently the most informative answer of all.

Switching

A method that does not suit you is not a failure of yours, and side effects vary between individuals in ways that cannot be predicted in advance.

Most side effects that appear in the first three months settle; those that persist beyond that generally do not.

Switching is normal, common and expected, and there is no obligation to persist with something that is making life worse.

General information only, not medical advice. Availability, licensing and guidance vary by country — discuss contraception with a qualified clinician or sexual health service.