Effects of the contraceptive patch and the vaginal ring on bone metabolism and bone mineral density: a prospective, controlled, randomized study.
BACKGROUND
This study was conducted to compare the effects of the combined contraceptive vaginal ring releasing 15 mcg of ethinylestradiol (EE) and 120 mcg of etonorgestrel daily with the effects of the contraceptive patch, a transdermal system that delivers a daily dose of 20 mcg of EE and 150 mcg of norelgestromin on bone turnover and bone mineral density (BMD) in young fertile women.


METHODS
On the basis of a randomized, computer-generated list, 40 women desiring contraception were assigned to a 12-month treatment with a patch delivering a daily dose of 20 mcg of EE and 150 mcg of norelgestromin (Evra, Janssen-Cilag, Italy) (Group A, n=20) or to a 12-month treatment with a vaginal ring releasing a daily dose of 15 mcg of EE and 120 mcg of etonorgestrel (NuvaRing, Organon, Italy) (Group B, n=20). Twenty patients underwent no treatment and were used as healthy controls (Group C, n=20). At 3, 6, 9 and 12 months, serum and urinary calcium, osteocalcin and urinary pyridinoline (PYD) and deoxypyridinoline (D-PYD) levels were measured. At baseline and after 12 months, lumbar BMD was determined by dual-energy X-ray absorptiometry.


RESULTS
In Groups A and B, urinary PYD and D-PYD at 6, 9 and 12 months were significantly reduced in comparison with basal values and Group C values (p<.05). In Groups A and B, serum calcium levels were significantly increased after 6 months. No significant difference was detected between Group A and Group B in urinary levels of PYD and D-PYD, in calcium levels and in osteocalcin levels. At 12 months, no significant difference was detected in spinal BMD values between the three groups and in comparison with basal values.


CONCLUSIONS
Both contraceptive systems exert a similar positive influence on bone turnover in young postadolescent women.
Massaro
Mariangela
M
Department of Gynecology and Obstetrics, University of Naples Federico II, via S. Pansini 5, Naples, Italy.
Di Carlo
Costantino
C
Gargano
Virginia
V
Formisano
Carmen
C
Bifulco
Giuseppe
G
Nappi
Carmine
C
D015502:Absorptiometry, Photon; D000596:Amino Acids / Q000652:urine; D000704:Analysis of Variance; D015519:Bone Density / Q000187:drug effects*; D001842:Bone and Bones / Q000187:drug effects* / Q000378:metabolism*; D003271:Contraceptive Agents, Female / Q000009:adverse effects*; D003274:Contraceptive Devices, Female / Q000009:adverse effects*; D017135:Desogestrel / Q000009:adverse effects; D004338:Drug Combinations; D004967:Estrogens / Q000009:adverse effects; D004997:Ethinyl Estradiol / Q000009:adverse effects; D005260:Female; D006801:Humans; D009644:Norgestrel / Q000009:adverse effects / Q000031:analogs & derivatives; D010091:Oximes / Q000009:adverse effects; D011446:Prospective Studies
D000596:Amino Acids; D003271:Contraceptive Agents, Female; D004338:Drug Combinations; D004967:Estrogens; D010091:Oximes; C044815:etonogestrel; D009644:Norgestrel; D004997:Ethinyl Estradiol; D017135:Desogestrel; C449219:norelgestromin