The definition of early puberty confuses even the best of the pediatric endocrinologists. The consensus(not made up of moms!) is age 8 for breast and maybe 6-7 for pubic hair depending on the ethnic background. Now with children of my own I see too much and am just as fearful of them developing at these "normal ages" as you are.
So it is relative. I try to explain to my patients that early puberty in the most cases other than the very very rare causes related to tumors are more of a concern for two issues-final height that may be compromised and the second is the biggest one for us parents-psychosocial-our psyche and our kids social!
Will my 3rd grader get her period? We don't want that!
I have a couple of parents after I have seen their child and testing was done who decided to let their child be and not intervene and I explained that this was completely ok.
Early puberty can be due to an early lack of inhibition of the pituitary hormones, the LH hormone pulses gradually and as it increases and matures it signals to the ovaries to make estrogen which in turn lead to ovulation, endometrial lining of the uterus and progesterone cycles with estrogen and eventually the menstrual cycle occurs. The physical symptom of estrogen effect is breast development, breast buds with tenderness unilaterally is normal and expected as I mentioned as early as 8. The key is rate of progression, degree of development and any evidence to be concerned for other reason.
To date there are many questions regarding environmental concerns. A very very smart pediatric endocrinologist at Harvard, Mary Lee devotes her life to this area, she has given some frightening lectures concerning environment and pollutants and their effect on animals. But honestly there is not conclusive evidence that indeed this product or that product causes early puberty and if we avoid it we will be fine (other than eating birth control pills of course!)
There is a strong relationship with obesity or even rapid weight gain and pubertal development, just as there is a strong relationship with anorexia and pubertal delay, so body fat or percentage is a factor that is becoming more understood with time.
The pubic hair is a separate issue, directed by male hormones that we all have-the adrenal gland usually kicks in prior to the female hormonal effect, we see body odor as an early finding around age 7.
Our kids get off of the soccer field and whew! we are not smelling our cute kid anymore, the adrenal gland has a "blip" around age 6,7,8 in some not till 12 or 13, these hormones mainly DHEAS and androstenedione can lead to the change in our sweat odor, development of pubertal hair rather than body hair in axillary and pubic area.
If the adrenarche-as it is called is due to an enzyme reason and there is an abundance almost excess of the adrenal hormones this can be a concern and does need workup. Again, usually presenting with rapid progression in symptoms, rapid height velocity and advancing bone age or maturity as seen on an xray done by your physician.
So I would have her seen by your pediatrician and the easiest thing they can do without stim testing as we call it (tests that tell us about the signalling), would be a bone age-xray of left hand, maybe a transabdominal pelvic ultrasound to look at the ovaries and endometrium and adrenals.
If there is no endometrial lining yet, if there are not many follicles on the ovaries and if the bone age is not advanced her final height is not at this time predicted to be compromised and she can be followed all the time with the intention of referring her if she progresses too quickly.
I have worked up girls right up to their 10th birthday depending on their bone age and ability to adapt.
The central precocious puberty or early puberty due to early signalling needs to be ruled out with testing done called a leuprolide test-patients baseline hormone levels measured and then are given leuprolide-a hormone that is a copy of the puberty signalling hormone, if her pituitary has been going off then her brain will respond due to its responsiveness already, if she is not in early puberty there will be low or little response. Labs are drawn after the medication is given and again the next day, measuring estradiol and LH and FSH-the pituitary hormones.
An endocrinologist does this testing and can best interpret it.
So given the family history with your girls, I would work closely with your pediatrician, see if they can plot her height, if she is growing rapidly, see if they are open to a bone age and also consider a transabdominal ultrasound and based on their results and your level of comfort consider referral as needed to a peds endo.
We see alot of early puberty, the diet at this time is not the cause based on any studies thus far. Wish it were that easy.
Hope this gives you some insight, keep us informed
My daughters are bi-racial (Caribbean Black/European White), however what about left breast developing and not the right.
I am going to visit my 5 year old Pediatrician/Endocinology and will try to get an appointment for the 8 year old.
As you mentioned adrenarche is indeed influenced by our background, african american, latin american, mediterranean and middle eastern children tend to have early adrenarche but not necessarily earlier puberty(meaning the menstrual cycle).
One side does usually start prior to the other and this can be completely normal-even in boys!(not the same degree of course and their's resolve usually)
Visiting your endo is a great idea, I have many sibs that come to see me and having the knowledge from their sibling is helpful and also the parents feel reassured and are more aware of the issues having looked into them with the previous child. Also remember each child is unique and one may not have had early puberty where another may indeed so the workup should be individualized, I imagine a bone age will help at your visit and maybe labs done as baseline based on the exam findings. keep us informed