Fig. 1.

Indicative oestrogen and progesterone profiles across the lifespan from childhood to senescence: a oestrogen (pmol∙L⁻¹). With regards to oestrogen, the menstrual cycle has 20 times more oestrogen than pre-puberty and pregnancy 35 times more oestrogen than the menstrual cycle; b progesterone (nmol∙L⁻¹). The menstrual cycle has 35 times more progesterone than pre-puberty and pregnancy almost 7 times more progesterone than during the menstrual cycle. Oral contraceptives users and post-menopausal women have similar levels of endogenous oestrogen and progesterone. Hypothalamic-pituitary forms of amenorrhea (not depicted here) do not show any evidence of oestrogen production based on urinary measurements [1]. In women, “oestrogen” includes the oestrone, oestradiol, oestriol hormones