Effect of Norplant contraceptive on the bones of Nigerian women as assessed by quantitative ultrasound and serum markers of bone turnover.
Levonorgestrel is a commonly used progestin-only contraceptive that is available as subdermal (Norplant) and intrauterine implants. Other progestin-only contraceptives such as injectable medroxyprogeterone acetate have been shown to decrease bone mineral density in long-term users. We used calcaneal ultrasound to compare the bone quality of Nigerian women between 25 and 50 years of age who had Norplant implants for 1-4 years to that of women who were not using any form of hormonal contraceptive. The mean stiffness index of women who had Norplant implants for as long as 4 years was not significantly different from that of controls. However, serum markers of bone turnover were significantly decreased in women with Norplant implants compared to age-matched controls. Serum bone-specific alkaline phosphatase was significantly decreased in subjects with Norplant implants for 1 year (13.7+/-6.0 vs. 23.0 U/L for controls, p = .001) and serum NTx was significantly decreased in subjects with implants for 3 years (10.6+/-4.9 vs. 17.6+/-7.7 bone collagen equivalents per liter for controls, p < .001). We conclude that although levonorgestrel contraceptive decreased overall bone turnover, it had no deleterious effect on the bone quality of women using Norplant implants for up to 4 years.
Vanderjagt
Dorothy J
DJ
Department of Biochemistry and Molecular Biology, University of New Mexico School of Medicine, Albuquerque, NM 87131-0001, USA.
Sagay
Atiene S
AS
Imade
Godwin E
GE
Farmer
Stephanie E
SE
Glew
Robert H
RH
D000328:Adult; D000469:Alkaline Phosphatase / Q000097:blood; D015415:Biomarkers / Q000097:blood; D015519:Bone Density / Q000187:drug effects*; D001842:Bone and Bones / Q000000981:diagnostic imaging / Q000378:metabolism*; D003094:Collagen / Q000097:blood / Q000187:drug effects*; D024042:Collagen Type I; D003271:Contraceptive Agents, Female / Q000008:administration & dosage / Q000009:adverse effects*; D003430:Cross-Sectional Studies; D004343:Drug Implants / Q000008:administration & dosage / Q000009:adverse effects; D005260:Female; D006801:Humans; D007436:Intrauterine Devices, Medicated / Q000009:adverse effects; D016912:Levonorgestrel / Q000008:administration & dosage / Q000009:adverse effects*; D008875:Middle Aged; D009549:Nigeria; D010455:Peptides / Q000097:blood / Q000187:drug effects*; D014463:Ultrasonography
D015415:Biomarkers; D024042:Collagen Type I; D003271:Contraceptive Agents, Female; D004343:Drug Implants; D010455:Peptides; C052929:collagen type I trimeric cross-linked peptide; D016912:Levonorgestrel; D003094:Collagen; D000469:Alkaline Phosphatase