I knew that average age of menarche (first time a girl menstruates) has fallen in the past century or so — the average used to be more like 14 or 15 and now it’s something like 12 or younger. What I didn’t know was how many factors go into the age at which a girl gets her period:
- overweight and obesity — not totally surprising — girls and women who are too thin to support a pregnancy may not ovulate or menstruate, so it would make sense that the reverse would be true
- endocrine-disrupting chemicals: “These include chemicals we are commonly exposed to in cosmetics, shampoos, cleaning products, baby bottles and children’s teething toys.” Makes me shudder. I’ve been exposed to a lot of people who shun the average cleaners and such on the store shelves, reaching for the “natural” products at health food stores and such, or just grabbing a big bottle of vinegar with a big box of baking soda to clean just about everything. Reading this makes me more likely to do the same.
- premature birth and low birth weight — interesting that being born at a low weight and/or too early might make you start your period earlier; not sure what to do about it though! It’s not like many women choose to have their babies prematurely without a very good reason!
- psychosocial stressors — okay, anything that says “stress” is believable that it would alter menstruation, but this was quite intriguing: “These stressors, including the absence of a father in the home and family dysfunction, also disrupt the endocrine system and are possible contributing factors to early puberty” [emphasis mine]. Yes, fathers are important — I just didn’t realize it could affect menarche!
- formula feeding — quite plausible! — “Breastfeeding appears to protect against early puberty in two ways: by contributing fewer calories than formula and by offering hormones and other growth factors that may protect against early puberty.”
- physical inactivity — seems to relate to the first point
- television viewing and media use — also seems to relate to the first point and the last one
Quite an interesting link! h/t to Bethany Midwives for the initial link