The contraceptive pill uses Definition 56.4’s own machinery: taken daily, its hormones hold the ovaries’ cycle in the suspended state (Proposition 57.5’s event 4 without any pregnancy) — no ovulation, no egg cell, nothing to fertilize. Prescribed by a doctor, who matches method to person; highly reliable when taken regularly — and offering nothing at all against infections, hence the condom’s standing partnership.
Examples
Example 59.4 (The shelf, sorted by link)
The other common methods, filed by their attacked link: hormonal implants and patches — the pill’s principle with better memory (months or years, no daily taking); the small devices a doctor places in the uterus — the meeting and implantation made to fail for years at a time; and the emergency pill, a within-days after-the-fact hormone dose that works chiefly by delaying an ovulation not yet happened — a last-resort brake, pharmacist-available, and no substitute for a method used before. What none of these do: anything against infection.