Description of estrogen types and potency production

Estrogens are hormones that are essential for growth and development, but even minuscule amounts of excess estrogen can have detrimental health impacts on living things. The core of estrogens is composed of 18 carbon atoms bonded together into four rings. Slight chemical differences in the first ring produce significant changes in the estrogens’ potency. (Illustration by Amy Caracappa-Qubeck, © Woods Hole Oceanographic Institution)