What is Oestrous cycle?
The '''oestrous cycle''' (U.S: estrous cycle) is the reproductive system in most [[mammal]]s.<ref>derived from [[Latin language|Latin]] ''oestrus''; originally from [[Greek language|Greek]] οἶστρος, meaning sexual desire)</ref> 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 [[hypothalamus|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 [[estrogen]]s and [[progesterone]]. However, species vary in the details. One difference is that [[animal]]s that have oestrous cycles reabsorb the [[endometrium]] if [[conception]] does not occur during that cycle. Animals that have menstrual cycles shed the [[endometrium]] through [[menstruation]] instead. Another difference is [[Sexual arousal|sexual activity]]. In species with oestrous cycles, females are generally only sexually active during the oestrus phase of their cycle. This is referred to as being 'in heat'. In contrast, females of species with [[menstrual cycle]]s can be sexually active at any time in their cycle, even when they are not about to [[ovulation|ovulate]]. [[Human]]s and some other [[primate]]s, do not have any obvious external signs to signal when ovulation occurs (concealed ovulation). Recent research suggests that women tend to have more sexual thoughts and are more prone to sexual activity right before ovulation (estrus).<ref>{{cite journal | author=Geoffrey Miller | title=Ovulatory cycle effects on Tip earnings by lap dancers: economic evidence for human estrus? | journal=Evolution and Human Behaviour |date=April 2007 | issue=28 |pages=375–381 | url=http://www.unm.edu/%7Egfmiller/cycle_effects_on_tips.pdf }}