From the article:
“Previous studies have shown that giving oral estrogen combined with progesterone as birth control pills is not effective in increasing bone density in girls with anorexia nervosa,” Misra said. “However, the impact of giving estrogen in a more natural, or physiological, form has not been previously studied in girls with anorexia nervosa.”
This National Institutes of Health-funded study explored, over an 18-month period, the effect of physiological estrogen replacement on bone accrual rates in 110 female patients with anorexia nervosa. These patients and 40 healthy-weight girls as controls were between ages 12 to 18 years, a common time for anorexia nervosa to start and also an important time for building optimal bone mass, Misra said.
[…] Those girls with mature bone received either placebo or a full adult dose of estrogen (100 micrograms of estradiol) given via a skin patch. This transdermal form is a natural form of estrogen, Misra said. Girls receiving estrogen also received cyclic progesterone pills to reduce the risk of endometrial cancer.
Girls with anorexia nervosa whose bones were immature received incremental low doses of oral estrogen, ranging from 3.75 to 11.25 micrograms of estradiol. These low, natural levels mimic estrogen levels seen in early puberty and avoid accelerating fusion of the growth plates, which would otherwise limit height potential, Misra said. Healthy-weight controls received no treatment other than calcium and vitamin D supplements, which all subjects received.
Using dual-energy X-ray absorptiometry (DEXA) bone density scans, the researchers assessed bone mineral density at the lumbar spine (lower back), hip and whole body. Physiological estrogen administration caused a significant increase in bone density at the spine and hip, compared with placebo, as found on DEXA Z-scores, the authors reported. However, Misra said that estrogen did not result in a complete “catch-up” to normal bone density measures. Girls with anorexia nervosa still had lower bone density than healthy-weight controls did.