Einfluss der Schwangerschaft auf die Messergebnisse der quantitativen Ultraschallsonometrie und den Knochenstoffwechsel

Objective The aim of this study was to determine prospectively the change in results of bone ultrasonometry measurement during pregnancy in healthy German women. Study design Quantitative ultrasonometry (QUS) of the phalanges was performed in 60 healthy, pregnant women. Measurements of amplitude-dependent bone propagation velocity (speed of sound; AdSOS) and the bone transmission time (BTT) were performed during the three trimesters of pregnancy in 60 patients. Results During pregnancy, a significant increase in body weight and body mass index (p<0.001) were observed. In accordance with bone ultrasonometry, a significant reduction in AdSOS was found in each trimester; AdSOS was significantly lower in the second and third trimesters compared with the first (p < 0.001). The BTT values also decreased significantly in the second and third trimesters compared with the first (p <0.001). No significant influence was found of possible risk factors such as family risk of osteoporosis, previous pregnancies, age at menarche and prior use of oral contraceptives on QUS measurement results. Conclusions During normal pregnancy, we found a significant reduction of quantitative ultrasonometry variables AdSOS and BTT in healthy pregnant women. This decrease had a large influence on the t score and Z score of QUS in our study and demonstrates therefore a possible clinical relevance. The decrease was independent of osteoporosis-related risk factors and the increase in body weight. More large-scale, prospective studies are needed to increase our knowledge about the mechanism of bone turnover during pregnancy and lactation.