you are all wrong and deeply retarded. human women have a MENSTRUAL cycle. ovulation is the MOST fertile period, but we can be bred at any time save for maybe two or three days as the cycle resets. there's no outward indication of this period of time that can be percieved. this is not heat.

many female mammals other than humans have an ESTRUS cycle, otherwise known as 'heat'. this is the ONLY time these animals can become impregnated and they have physical tells that telegraph it outwardly to males. otherwise there's barely any chance of reproduction whatsoever. it's a different term for a different thing. learn to do literally any amount of research and for the love of god learn human biology. you will consistently come off as retarded without basic knowledge like this.