P03.01: The silent myometrial contraction in pregnancy



Characterization of the silent focal myometrial contraction (SFMC) in pregnancy as observed during routine ultrasound examination.


544 healthy pregnant patients, 122 of them nulliparas, were scanned during mean time of 15 minutes. The median age of the patients was 27 years with the range of 15–46 years. The median gravidity and parity of G3P2. The majority were referred for routine second trimester malformation screening, or weight estimation at third trimester. The gestational age was established by ultrasound standard parameters. The occurrence, location, and myometrial thickness were analysed versus gestational age and parity. The Chi-square test was implemented in the statistical analysis.


The frequency of SFMC was 22%, significantly higher among the multiparas 24% then the nulliparas 15%. No statistical difference was observed between the first and the second trimester among the multiparas and the nulliparas, combined data of 38%, 21% in accordance. No SFMC were observed among the third trimester nulliparas and only 5% among the multiparas. The predominant location was the anterior wall 59% and thereafter the posterior one 30%, 25% were under the placenta. The myometrial thickness measured was in the range of 12–47 mm, with the median of 27.5 mm. 70% of the measurements were in the range of 21–31 mm.


The SFMC is a frequent event during pregnancy in the first and the second trimester. The data provided can help to distinguish between the SFMC and leiomyoma.