Hormones
Get to know the hormones behind how you feel. Guides to estrogen, progesterone, testosterone, cortisol and others, explaining what each one does, what shifts them, and what your levels can and cannot tell you.
All guides
Birth control, mood and nutrients: what the evidence says
Hormonal contraception affects mood in some women and not others. What the research really says, which nutrient claims are oversold, and how to judge a method.
Cortisol, stress and women’s health
What the stress hormone cortisol does, how it changes through the day, what high or low levels can mean, and where the cortisol hype misleads.
AMH and fertility: what your level really means
What the AMH test measures, how to read your own number, why the pill lowers it, and why a low result says less about conceiving than you have been told.
Testosterone in women: where it comes from and what it does
Yes, women produce testosterone. Where it is made, how much compared with men, what it does, and why a blood test cannot settle whether yours is low.
Progesterone in women: what it does and how it changes
Progesterone does far more than support pregnancy. What it does across the cycle and life stages, what low progesterone can mean, and how it fits into HRT.
Estrogen in women: what it does and how it changes
Estrogen shapes far more than fertility. What estrogen does across the body, how levels change through life, and what high or low levels can mean.