Strange, but true: Your breasts change shape throughout the course of your monthly cycle. According to a study in the journal Ethology and Sociobiology, your breasts are more asymmetrical during Week 1 (your period week) and Week 4 (your premenstrual week) when estrogen is low. They’re more symmetrical during Week 2 (which starts 8 days after the onset of your period) when estrogen is high. And they’re at their most symmetrical during ovulation at the end of Week 2 (the mid-point of your cycle). Why the fluctuation in shape? The researchers theorize it may be a subtle cue to men that indicates when you’re approaching the most fertile phase of your cycle.
Your breast shape changes through your cycle
Gabrielle Lichterman, founder of Hormonology® and a longtime women’s health journalist, pioneered the growing movement among women to live in sync with their menstrual cycles and know more about all the ways their hormones impact their moods, health and behavior. This movement was launched in 2005 with Gabrielle's groundbreaking book, 28 Days: What Your Cycle Reveals about Your Love Life, Moods and Potential, and her creation of Hormonology®. She offers a variety of tools--including her popular free Hormone Horoscope® app, eBooks, infographics, videos and tips--to share vital information about hormones.