In two pregnant primigravidae with signs of imminent necrosis of a myoma treatment with micronized progesterone, preparation Utrogestan R , was successful. After oral and vaginal treatment with a dose of 300 - 600 mg/day the symptoms receded within several days. Complete regression of symptoms was recorded within one to two weeks. Both women terminated their pregnancy during the 37th - 38th week and were delivered of healthy infants. One women gave birth to the infant by Caesarean section, the other one per forcipem Shutte. During surgery on the myoma no signs of degeneration were found and it was left in situ. Progesterone treatment prevented in both women surgery on account of an acute abdomen. Treatment was monitored by ultrasonographic assessment of the flow in afferent vessels of the myoma. This measurement revealed marked changes, i.e. an increased flow. At the onset of treatment there was a small difference between the indices of pulsatility (PI) and resistance (RI). This difference increased gradually, and also the difference between systole and diastole in the investigated vessels increa- sed. This led to an increased flow and blood supply of the myoma. Thus evidence can be provided that large doses of natural progesterone have a favourable effect on the blood vessels and increa- se the blood flow in the vascular wall at the site of the myoma.

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