Logan has dropped from the 50th % in weight to the 30% and is still in the 90th% for his length. In our case, I think it is a prediction of things to come b/c I am 6'1" and his dad is 6'6". My husband is pretty stocky, but I have always been tall and skinny. We expected nothing less from him! Does tallness run in your family? I think the % are just to give you and mostly the doctors an idea of how your baby is growing and to make sure that he is gaining enough/too much weight. I have heard that when your child is 2 years old, you can double their height and that will be close to how tall they will be when they are an adult. Don't know if it's true, though!
Andrea

My family has a tendency to be very very thin in the younger years, up until about 30 & then avg out. We aren't short, but not exceptionally tall. We seem to give a tall appearance according to everyoe who always says how tall we are. I am only 5'5". Hubby too was thin all his life & now at 36 he could us to lose a few pounds. He's 6 ft.

The percent only means that he's bigger than half of the other babies measured, and smaller than the other half. Timberly's always been in the 50%, and on her growth chart, she follows the average line pretty well (both height and weight). SO yeah, probably you have a basketball player on your hands :)

The charts are just a guideline that doctors use to indicate potential problems. Babies grow on a curve, and any deviation from their curve is a sign of something wrong. Genetics is what determines the size and weight of most babies (unless they are malnourished or whatever). According to the charts, my nine month old is the size of an average four month old, but she is perfectly healthy and larger than I was at 12 months.

The heights of you and your husband are more accurate indicators of eventual height. In your case it is likely you will end up with a daughter slightly taller than average, anywhere from 5'5 to 5'8. Our DS started out in 90 percentile in height and has dropped back to more like 60 percent when he was two years old. My husband and I are both 5'7 and I suspect he will end up taller than his Dad.

Trish

There was a piece on our local news the other night about the % chart. They were compiled several decades ago ('50s or '60s?) using just 100 or so children - all white, formula fed babies from the midwest. The charts are currently being redone using a wider focus group.
Here are two paragraphs from the website linked below:
Existing growth charts for children aged 2-18 years were based on a nationally representative
sample, but charts for those up to age 2 were based on a study since shown to have several
limitations, said Dr. Dewey, associate director of the Program in International Nutrition and
professor of nutrition at the University of California, Davis.
The sample was too homogeneous, growth measurements were made infrequently, and most
babies were bottle-fed, she said.
(Scroll down through the article to read more.)
In fact, if you do a Yahoo search on "percentile charts for babies," you will find 500 some hits! ~ Suzie

Here is a link that might be useful: Growth chart link

The charts have been updated. You can ask your pediatrician for information about the chart they use (when was it put into use for example, to see if it's recent).

Sometimes, maybe most of the time people do stay on their growth lines into adulthood. Sometimes they don't for no good reason at all, or at least for no known reason. Babies who have been small, and who have been small as children can sprout up tall with the changes of puberty. Some can go the other way, as if they just started out fast and caught up to themselves in adolescence and adulthood. Because I've seen both of those happen (plus a lot of people who seemed to maintain their same percentiles) I wouldn't plan on anything too much.

The percentiles are mainly to catch problems. Babies can't give detailed verbal information about their symptoms. Tracking their head circumference can be the only way to catch some scary problems early. Tracking their height and weight percentiles can be the only way to catch or even know to look for some metabolic problems or things that can cause a 'failure to thrive' which is a major symptom.

The cdc charts were revised in 2000. Prior to that they were dated from 1977 and tended to be more representative of formula-fed babies. These page address can give up to date information. The first address is to the 'background' page which explains the differences and how the 2000 charts are different. The second page has links to those updated clinical charts. They appear to be printable and in pdf format.
http://www.cdc.gov/nchs/about/major/nhanes/growthcharts/background.htm
http://www.cdc.gov/nchs/about/major/nhanes/growthcharts/clinical_charts.htm

This page address has a kind of intermediate chart set for breastfed infants. They were prepared in 1994 and is based on (only) 226 breastfed infants who did not have any solids before 4 months of age. These are only age/length and age/weight charts. (The units are weight in kilograms, length in centimeters, and age in months).
http://www.promom.org/bf_info/growth.html

make sure your pediatrician is using the most up to date charts