Oestrous cycle

(Redirected from Oestrus)

The oestrous cycle (U.S: estrous cycle) is the reproductive system in most mammals.[1]

Reproductive hormones cause the cycles to start after puberty in sexually mature females. They are interrupted by non-breeding phases or by pregnancies. Usually estrous cycles continue until death.

Differences from the menstrual cycle

Mammals share the same reproductive system, including the regulatory hypothalamic system that releases gonadotropin-releasing hormone in pulses, the pituitary that secretes follicle-stimulating hormone and luteinizing hormone, and the ovary itself releases sex hormones like estrogens and progesterone.

However, species vary a lot in the details. One difference is that animals that have oestrous cycles reabsorb the endometrium if conception does not occur during that cycle. This is referred to as being 'in heat'. Humans, and some other primates, do not have any obvious external signs to signal when ovulation occurs (concealed ovulation).[2][3] Nevertheless, this is nothing as obvious as the frenzy which other mammals show during 'heat'.

References

  1. derived from Latin oestrus; originally from Greek οἶστρος, meaning )
  2. Geoffrey Miller (2007). "Ovulatory cycle effects on Tip earnings by lap dancers: economic evidence for human estrus?" (PDF). Evolution and Human Behaviour (28): 375–381. {{cite journal}}: Invalid |display-authors=1 (help); Unknown parameter |author-separator= ignored (help); Unknown parameter |month= ignored (help)
  3. Susan B. Bullivant; Sarah A. Sellergren; Kathleen Stern; et al. (2004). "Women's sexual experience during the menstrual cycle: identification of the sexual phase by noninvasive measurement of luteinizing hormone". Journal of Sex Research. 41 (1): 82–93. doi:10.1080/00224490409552216. PMID 15216427. {{cite journal}}: Unknown parameter |author-separator= ignored (help); Unknown parameter |month= ignored (help)

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