It's hard to be "ethnically correct" when assessing growth in international adoption. Many of the available country-specific growth charts are out-of-date, from a small sample size, drawn from ethnic groups that may not represent your child's ethnicity, based on malnourished populations, or all of the above. US growth charts aren't perfect either, but they are drawn from large population surveys, and were recently revised to better reflect the racial-ethnic diversity and combination of breast- and formula-feeding in the US.
In 2006, the WHO (World Health Organization) released new international birth-5yo charts based on 8,500 children from Brazil, Ghana, India, Norway, Oman and the USA. Their unique approach was to select children whose care meets recommended health promotion standards (breastfeeding, standard pediatric care, anti-smoking, etc) so that the charts would represent how children should grow, not necessarily how they are growing. Their big finding was that "child populations grow similarly across the world’s major regions when their needs for health and care are met."
However, most international adoptees are bottle-fed and often do not receive ideal or even adequate care. Our default charts are still the revised CDC/NCHS (US) growth charts published in 2000, if only because we by now have years of experience following ethnically diverse children pre- and post-adoption on these charts. Still, it can be interesting to plot children on country-specific growth charts, so here's a smörgåsbord of US, premature, and country growth charts.
US Growth Charts
Nellhaus male and female head circumference charts for children over 3 years old (I don't love these charts, as the pooled data is from 1948-1965, and is not as "interracial" as advertised, but we don't have many other options for older children).
These 2010 United States head circumference growth reference charts: birth to 21 years, by Rollins et al., look better than Nellhaus for plotting head size in kids older than 2-3yo.
WHO Growth Charts
Charts for Premature Infants
26wks to 1year chart, for boys and girls
Fetal-infant growth chart for 22wk-2mo preterm infants from a meta-analysis of published reference studies
Charts based on birthweight categories (for when gestational age is unclear). LBW (low birthweight) is for birthweights from 1500g to 2500g. VLBW (very low birthweight) is 1000g to 1500g at birth.
Chinese Growth Charts
The widely available China growth charts are from a sample of Southern Chinese children in Hong Kong in the 1960s, and thus quite out of date and not necessarily ethnically appropriate. These can be found on the Families with Children from China (FCC) site.
Another useful reference could be "Infant feeding and growth of Chinese infants: birth to 2 years", which tracked growth in healthy, fullterm, formula-fed infants in 1985 Hong Kong and found that at 2 years old, infants were -0.6 standard deviations (SDs) lighter and -0.4 SDs shorter than US growth data, even with similar protein/calorie intake to Caucasian infants.
An article called "Updated gestational age specific birth weight, crown-heel length, and head circumference of Chinese newborns" based on preterm and term births in Hong Kong has weight, height, and head circumference charts.
Guatemalan Head Circumference Charts from Dr. Montiel
Note - these are unofficial charts based on his personal experience
Indian Growth Charts
The Indian Academy of Pediatrics has recently published new recommendations for growth monitoring of children from India, including growth charts based on "affluent urban children from all major zones of India measured between 1989-91"; this is actually an advantage, as they are more likely to reflect how Indian children can and should be growing:
Korean Growth Charts
These 2017 Korean National Growth Charts look higher quality.
Nepalese Growth Charts
An article with weight, height, and head circumference data for relatively healthy, higher socioeconomic status Kathmandu term infants:
Nepal - Infant Growth Charts, which I adapted from the article above
Russian Growth Charts
From Dr. Tsepkova, via Karen's Adoption Links. Of unknown sample size and quality ... we prefer the CDC growth charts for Russian children.
Taiwan Growth Charts
From a parent who lives in Taiwan. These are the growth charts that seem to be a part of children's shot records. The less-than-smooth percentile lines does make me wonder whether the sample size or statistical techniques were adequate. I'm told they were in use from 1999-2009, when they switched to the WHO charts above.
The 1st page top left has head size in centimeters, by age in months. The rest of the 1st page is weight in kg by months and then by year. The 2nd page is height in cm by age. Percentile lines are in the legend.
Vietnamese Growth Charts
Adopt Vietnam has links to a few Vietnamese growth charts; however, they are not easy to interpret and are of unknown date and sample size.