[Pregnancy induced hypertension (PIH) and osteoporosis]

The authors have already reported that the bone density of normal pregnant women might be kept at the same density as in normal non-pregnant women. However, it might be decreased in women with pregnancy induced hypertension (PIH) by estimating serum calcium levels, serum levels of calcium regulating hormones and calcium secretion into the urine. In order to demonstrate this theory, the degree of bone density in the second metacarpal bone of normal or PIH pregnant women was measured by X-ray using microdensitometry method (MD method). In MD method, six indices, such as MCI, d, GSmin, GSmax, sigma GS/D and densitometric pattern, are calculated by computer analysis of the X-ray of the bilateral hands. By the evaluation of the degree of bone atrophy, scores such as 0 better than the regression line of healthy women, which were prepared according to each age, 1 until 1 delta to the aggravation, 2 until 2 delta, and 3 more than 2 delta were totaled and evaluated as normal, initial stage of bone atrophy, 1st degree of bone atrophy, 2nd degree of bone atrophy and 3rd degree of bone atrophy for 0-3 scores, 4-9 scores, 10-12 scores and 13-18 scores, respectively (delta = 1 S.D.). The metacarpal index (MCI) of normal pregnant women in 3rd trimester was more than the mean in all cases, while cases more than 2 delta of the mean were noted in 29.4% of mild PIH and 11.8% of severe PIH, and a decreasing tendency of width of bone cortex was considered in PIH women. On the other hand, width of bone marrow (d) increased significantly in mild and severe PIH women. In the index for the density of only bone cortex area (GSmax) in PIH women, cases less than mean -1 delta were noted in 29.3% of mild types and in 11.8% of severe types respectively, and a high incidence was noted even though it was insignificant compared with 7.4% of normal pregnant women. In the index of the densities of bone cortex and bone marrow (GSmin), cases less than mean -1 delta were noted more frequently in PIH women than normal pregnant women, but in the index of bone density per unit length (sigma GS/D) no differences were noted between PIH and normal pregnant women.(ABSTRACT TRUNCATED AT 400 WORDS)