Hormones can feel like a complicated subject — full of charts, abbreviations and conflicting advice. In reality, the rhythm of your cycle is shaped by just a few key players, working together in a quiet, repeating dance.
The four main hormones
Estrogen
Estrogen rises during the first half of your cycle. It supports energy, mood and the build-up of the uterine lining, and it helps signal that ovulation is approaching.
Luteinising hormone (LH)
A surge of LH triggers ovulation itself. It is a short, decisive signal that the egg is ready to be released.
Progesterone
After ovulation, progesterone rises and stays elevated through the second half of the cycle. It supports a possible pregnancy and gently raises basal body temperature.
Follicle-stimulating hormone (FSH)
FSH helps your ovaries prepare follicles at the start of each cycle. It works closely with estrogen to set the stage for ovulation.
Why this matters in daily life
These hormones do not only affect fertility. They influence energy, sleep, skin, appetite, focus and mood. Knowing roughly where you are in your cycle can make many small daily experiences feel less random.
"When you understand the hormonal weather of your cycle, you stop fighting your body — and start working with it."
A calmer way to learn
You do not need to memorise charts. By gently observing your cycle over time — your temperature, your mood, your energy — the role of each hormone becomes clearer through experience.
If anything in your body feels off, please speak with your doctor. The Daysy Journal is educational and is not medical advice.
From the makers of this Journal
Bring cycle awareness into your morning.
The Daysy Fertility Tracker is a hormone-free way to understand your cycle more clearly — designed for women who want quiet, daily insight.