Hormones and the Menstrual Cycle How They Shape Your Body and Mood

Estrogen is the hormone that, among others, is responsible for kick-starting puberty and is behind the growth of breasts, cercival fluid and other body changes. It also dominates the first phase of the cycle and, among other things, enables an egg to be fertilized. Just before ovulation, the hormone concentration is at its highest and ensures that your basal body temperature (BBT) is low.

Right after your period, estrogen levels begin to rise steadily and reach their peak just before ovulation.

• Builds up the uterine lining to prepare for a possible pregnancy
• Supports the maturation of the egg
• Improves skin appearance, hair texture, and boosts libido
• Enhances cognitive functions like focus, memory, and creativity

• We often feel more talkative, energetic, and socially open
• Confidence and creativity tend to increase

After ovulation, progesterone takes the lead. It is created as a result of ovulation and is produced by the corpus luteum, a temporary gland formed from the follicle that released the egg. This hormone plays a crucial role in the second half of the menstrual cycle, known as the luteal phase. It is the "period hormone" in that a drop in progesterone at the end of the luteal phase is the body's signal to start menstruation.

Luteal phase (Days 15–28): Following ovulation, progesterone levels rise significantly and dominate the hormonal landscape.

• Prepares the uterine lining for potential implantation
• Regulates body temperature — which rises slightly and measurably
• Calms the nervous system
• Supports sleep quality and inner balance

• We may feel more reflective, sensitive, or even a little melancholic
• There's often a stronger need for warmth, rest, and emotional structure

Women produce testosterone too, just in smaller amounts than men. In the female body, testosterone reaches its peak around the time of ovulation and plays an important role in both physical and emotional wellbeing.

Late follicular phase to ovulation (Days 10–15)

• Boosts libido and sexual desire
• Supports muscle maintenance and metabolism
• Enhances motivation and strengthens self-confidence
• Promotes red blood cell production (erythropoiesis)

• Heightened sense of attraction, drive, and assertiveness
• A powerful “I can do anything” feeling

FSH, or follicle-stimulating hormone, is produced by the pituitary gland and plays a crucial role in initiating a new menstrual cycle. It stimulates the follicles of the ovary to mature and release an egg for ovulation.

Early follicular phase (Days 1–10)

• Stimulates the maturation of follicles (egg sacs) in the ovaries
• Promotes estrogen production
• Triggers the process that leads to ovulation

LH, or luteinizing hormone, is the key signal for ovulation. Just before ovulation, there’s a sharp rise known as the LH surge, which causes the dominant follicle to rupture and release the egg.

Days 12–16 – during the LH surge

• Triggers the release of the egg (ovulation)
• Transforms the mature follicle into the corpus luteum
• Stimulates the production of progesterone

• A surge of excitement, increased attraction, and focus on social interaction
• Many women experience peak confidence during the LH surge

Cortisol, along with adrenaline, is one of the body’s key stress hormones. Both are released by the adrenal glands and serve to mobilize energy reserves while preparing the body for a potential “fight or flight” response.

During physical, emotional, or psychological stress

• Activates stored energy for immediate use
• Regulates immune system activity
• Prepares the body for acute stress situations