Comparison of transvaginal sonography in recumbent and standing maternal positions to predict spontaneous preterm birth in singleton and twin pregnancies

Abstract

ABSTRACT

596: Serial cervical length determination in twin pregnancies reveals four distinct patterns with prognostic significance for preterm birth

“…Our observations provide evidence that this hypothesis is correct. Gibson 34 In contrast, this was not observed in other studies 34,36,[42][43][44][45][46][47][48] For example, Khalil et al reported serial measurements of cervical length in 209 women with twins at 20-23 weeks and 3-5 weeks later. 46 There were no differences in the predictive value of the first cervical length measurement, the follow-up cervical length measurement, and change in cervical length between the two measurements.…”

“…The association between a short sonographic cervical length and the risk of subsequent PTB is well-established in singleton 11, 23-28, 52-61 and twin gestations 12,[29][30][31][32][33][34][35][36][37][38][39][40][62][63][64] . Since cervical length changes over time as the time of the onset of labor approaches, we propose that cervical shortening detected with serial sonographic examinations may yield information about the risk of PTB which is not available at the time of the routine sonographic examination in the midtrimester.…”

“…7,11 The early prediction of PTB in twin pregnancies is of major importance as it may assist clinicians in identifying women with twin gestations who are at high risk of PTB and who may benefit from closer monitoring, administration of corticosteroids for fetal lung maturation and other potential preventive interventions such as progesterone and cervical pessary. [12][13][14][15][16][17][18][19][20][21][22] Sonographic measurement of cervical length (CL) at mid-gestation has been shown to be predictive of PTB in singleton 11,[23][24][25][26][27][28] and twin gestations 12,[29][30][31][32][33][34][35][36][37][38][39] . This, in turn, has led to the relatively common practice of serial monitoring of CL during the second trimester in women at risk of PTB, including women with twin gestations.…”

“…34,36,[42][43][44][45][46][47][48] Overall, most investigators have reported that serial measurements of CL do not improve the prediction of PTB. However, available studies have several limitations, including a small sample size and variability in the timing of CL measurement as well as the definition of cervical shortening.…”

Twin and Preterm Labor: Prediction and Treatment

“…Evaluation of the cervix with the woman in the upright position permits earlier detection of funneling. This may enable earlier and more appropriate intervention to avoid spontaneous preterm birth [41].…”