A closer look at oestradiol, the star of female hormones

Oestradiol is a female hormone that plays a key role in the development of sexual characteristics and in the menstrual cycle. It belongs to the oestrogen family, of which it is one of three distinct members. The other two are oestrone and oestriol. In this article, we examine the main functions of oestradiol, as well as some possible consequences of hormonal imbalance.

The role of oestradiol in the female reproductive system

Development of secondary sexual characteristics

During pubertal development, oestradiol's main function is the development of secondary sexual characteristics in women. It plays a role in particular in breast growth, fat distribution around the body, and the onset of periods.

The functioning of the menstrual cycle

Oestradiol also plays a crucial role in the course of the menstrual cycle in women. During the first phase of the cycle, known as the follicular phase, oestradiol levels gradually increase, thereby stimulating the maturation of the ovarian follicles and the thickening of the endometrium.

The production of oestradiol in the female body

The ovaries: the main site of production

In a woman's body, the ovaries are the main producers of oestradiol. This process takes place under the influence of luteinising hormone (LH) and follicle-stimulating hormone (FSH), which are themselves secreted by the pituitary gland.

Factors influencing the release of oestradiol

Several factors can influence the production of oestradiol in a woman, including:

• Age: in general, oestradiol production decreases with advancing age, and more markedly so during the transition period towards the menopause.
• The phase of the menstrual cycle: as mentioned above, oestradiol levels fluctuate throughout the menstrual cycle, with peaks during the follicular phase and before ovulation.
• Physiological factors: diet, physical exercise and sleep can also have an impact on oestradiol production.
• Stress: chronic stress levels can impair ovarian function and, consequently, oestradiol production.

Hormonal imbalances: possible effects on the body

An imbalance in oestradiol levels can cause various symptoms in a woman and even affect her overall wellbeing. Some of these symptoms are:

• Menstrual cycle disorders: an abnormal level of oestradiol can cause an absence of periods (amenorrhoea), irregular cycles, or atypical vaginal discharge.