How do pubic lice reproduce? - briefly
Female pubic lice deposit 1–2 eggs (nits) on each hair shaft daily; the eggs hatch in about seven days, and the emerging nymphs reach sexual maturity within two weeks, allowing continuous generation turnover.
How do pubic lice reproduce? - in detail
Pubic lice (Pthirus pubis) reproduce through a direct sexual process that follows a tightly timed life cycle. Adult females mate once with a male, after which they become capable of laying eggs, known as nits. The copulation occurs on the host’s hair shafts, where the male grasps the female with his claws and transfers sperm via the genital opening.
After fertilization, a female deposits 1–2 eggs per day. Each egg is cemented to a hair shaft close to the skin surface using a proteinaceous glue that resists removal. An average clutch contains 10–30 eggs, and the total lifespan of a female includes the production of several clutches before death.
Egg development requires approximately 6–10 days at typical body‑temperature conditions (35–37 °C). During this period, the embryo undergoes embryogenesis within the chorion, culminating in the emergence of a nymph. The nymph resembles a miniature adult but lacks fully developed genitalia and functional wings.
The nymph progresses through three successive molts (instars). Each molt lasts about 3–4 days, during which the insect sheds its exoskeleton and enlarges. After the third molt, the specimen reaches sexual maturity and begins reproducing. The complete cycle—from egg to fertile adult—occupies roughly 2–3 weeks.
Reproductive output is rapid: a single fertilized female can generate up to 30 – 40 viable offspring within a month. This high fecundity, combined with the lice’s limited mobility, ensures population expansion on the host and facilitates transmission through close personal contact, especially sexual contact, or via contaminated clothing and bedding.
Environmental factors such as temperature and humidity influence developmental speed. Higher temperatures accelerate embryogenesis and molting, while low humidity can impair egg adhesion and increase mortality. Optimal conditions on the human body maintain a stable environment that supports continuous reproduction.