A prospective study of heparin-induced osteoporosis in pregnancy using bone densitometry.
OBJECTIVE
Our purpose was to evaluate the subclinical occurrence of heparin-induced osteoporosis in pregnancy, by means of bone densitometry.


METHODS
A prospective, consecutive cohort of 14 pregnant women requiring heparin therapy and 14 pregnant controls matched for age, race, and smoking status was identified by 20 weeks' gestation at a university medical center. Proximal femur bone density measurements were taken at baseline, immediately post partum, and 6 months post partum in the cases and controls. Vertebral measurements were also obtained on both groups immediately post partum and 6 months post partum. Bone density as a function of heparin dosing and duration was examined. Nonparametric statistical tests were used for all comparisons.


RESULTS
Five of 14 cases (36%) had a > or = 10% decrease from the baseline proximal femur measurements to immediate postpartum values versus none of the 14 matched controls (p = 0.04). Mean proximal femur bone density measurements also decreased in the cases (p = 0.01); this difference continued to be statistically significant 6 months post partum (p = 0.03). No dose-response relationship could be demonstrated.


CONCLUSIONS
Heparin adversely affected bone density in about one third of exposed patients.
Barbour
L A
LA
Department of Medicine, University of Colorado Health Sciences Center, Denver 80262.
Kick
S D
SD
Steiner
J F
JF
LoVerde
M E
ME
Heddleston
L N
LN
Lear
J L
JL
Barón
A E
AE
Barton
P L
PL
D015502:Absorptiometry, Photon; D000328:Adult; D015519:Bone Density; D016022:Case-Control Studies; D004305:Dose-Response Relationship, Drug; D005260:Female; D005269:Femur / Q000000981:diagnostic imaging / Q000502:physiology / Q000503:physiopathology; D006493:Heparin / Q000009:adverse effects*; D006801:Humans; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000502:physiology / Q000503:physiopathology; D010024:Osteoporosis / Q000139:chemically induced* / Q000000981:diagnostic imaging / Q000503:physiopathology; D011247:Pregnancy; D011248:Pregnancy Complications / Q000139:chemically induced* / Q000000981:diagnostic imaging / Q000503:physiopathology; D011446:Prospective Studies
D006493:Heparin