Bone Density Appears to Recover After Adolescents Discontinue Injected Contraceptive
Lower bone density appears to recover in adolescent females once
they stop using the injected contraceptive depot medroxyprogesterone
acetate (DMPA), according to a study funded by the National Institute
of Child Health and Human Development of the National Institutes
Previous studies had shown that women who use DMPA, marketed under
the brand name Depo-Provera, experience a loss of bone mineral
density during the time they are using the contraceptive. Because
women are developing a large amount of their bone mass from ages
15 to 19, researchers were concerned that DMPA use might place
adolescents at higher risk for bone fracture or osteoporosis later
“This study shows that after adolescents stop using DMPA,
their bone density can increase to levels comparable to those of
other women in their age group,” said Duane Alexander, M.D.,
Director of the NICHD.
The study authors wrote that 10 percent of U.S. female adolescents
from 15 to 19 who are using birth control use DMPA, as compared
to 3 percent of U.S. women overall.
Researchers believe that DMPA interferes with bone mineral density
by lowering levels of estrogen, a hormone that promotes bone mineral
density in women.
The findings appear in the February Archives of Pediatrics and
Adolescent Medicine. The study was conducted by Delia Scholes,
Ph.D., of the Group Health Cooperative in Seattle, Washington,
and her colleagues.
To conduct the study, the researchers measured hip, spine, and
whole body bone mineral densities in 170 healthy female adolescents
ages 14 to 18. Of these, 80 had used DMPA, and 90 had not. Some
of the 90 who had not used DMPA had used other forms of contraception,
including oral contraceptives. Oral contraceptives also contain
hormones. Some contain a combination of the hormones estrogen and
progestin, some contain only progestin. It is not known whether
oral contraceptive use affects bone mineral density and NICHD is
currently supporting a study to address this issue.
The researchers measured the participants’ bone mineral
densities when the study began, and every six months thereafter
for the next two to three years. During the course of the study,
61 women stopped using the contraceptive.
The researchers found that DMPA users had a greater reduction
in bone density findings than did non-users.
Dr. Scholes explained that these bone density losses seen among
the DMPA users occurred at a pace similar to those experienced
by women progressing through menopause.
Once the women stopped using DMPA, they experienced significant
gains in bone density. The study authors wrote that the increase
in bone mineral density after discontinuation of DMPA is similar
to the bone mineral density increase after a woman stops breast
“The potential loss of bone density is one consideration
of the many that go into a woman’s choice of contraceptive
method,” Dr. Scholes said.
The researchers wrote that it is impossible to know what the women’s
bone density would have been if they had never taken the drug.
They added, however, that 12 months after these women stopped using
DMPA, their average bone mineral density scores were “at
least as high as those of the comparison women at all of the anatomical
The current study was conducted to follow up an earlier study
of older women (18-39 years old.) That study found that the older
women lost bone density while using DMPA and increased bone mass
after discontinuing the contraceptive. However, the younger women
in the current study both lost bone density and increased bone
density more rapidly than did the older women in the previous study.
“This study provides evidence that DMPA use by adolescents adversely
impacts [bone mineral density] at key anatomical sites,” the
study authors wrote. “However, these results in teens and
those from our previous cohort provide reassurance that bone
loss is regained, even in younger users.”
The current study is among several funded by NICHD to evaluate
the impact of DMPA on bone density in women, explained the study’s
project officer, Steven Kaufman, M.D., M.S., of NICHD’s Contraception
and Reproductive Health Branch. These studies are looking at the
effect of DMPA on bone health in women of various age and racial
“Our goal in funding these and other studies is to provide
women with reliable information on which to base their contraceptive
choices,” Dr. Kaufman said. “Depo-Provera is one of
the most effective contraceptives — its side effects need
to be weighed against the potential consequences of an unintended
pregnancy that could result from using a less effective method.”
On November 17, 2004, the U.S. Food and Drug Administration issued
a “black box warning” for DMPA, stating that prolonged
use of the drug may result in significant loss of bone density,
that the loss is greater the longer the drug is administered and
that bone density loss may not be completely reversible after discontinuation
of the drug.
The FDA warning states: “Depo-Provera Contraceptive Injection
should be used as a long-term birth control method (e.g. longer
than 2 years) only if other birth control methods are inadequate.” The
black box warning is available at http://www.fda.gov/medwatch/SAFETY/2004/DepoProvera_Label.pdf.
Other authors of the study were: Group Health investigators Andrea
Z. LaCroix, PhD, Laura E. Ichikawa, MS, and William E. Barlow,
PhD.; and the University of Washington School of Medicine’s
Susan M. Ott, MD.
The NICHD is part of the National Institutes of Health (NIH), the
biomedical research arm of the federal government. NIH is an agency
of the U.S. Department of Health and Human Services. The NICHD
sponsors research on development, before and after birth; maternal,
child, and family health; reproductive biology and population issues;
and medical rehabilitation.