Abstract
Objective
To determine whether transvaginal ultrasound assessment of the cervix is superior to
transabdominal ultrasonography in evaluating the cervical canal in the second trimester
and to see which one is more accurate in predicting preterm labor.
Patients and Method
The study entailed 294 women with singleton pregnancy, who attended our antenatal
clinic for routine care. Each woman underwent a transabdominal and endovaginal
ultrasonographic cervical length measurement at 20-24 weeks. Women with risk factors
for preterm deliveries like history of preterm delivery, cervical incompetence, uterine
abnormalities, and previous cervical surgery were excluded. Maternal and fetal data were
collected. Statistical comparison was made between the two ultrasonographic methods
for gestational age at birth and parity.
Result
10.8 % of the women delivered prematurely. Transvaginal ultrasonographic cervical
length measurements of term and preterm deliveries showed a statistically significant
difference (P<0.05) but no significant difference was found in transabdominal
measurements (P>0.05). Although transvaginal cervical length measurements showed a
statistically significant difference between primiparous and multiparous women (P<
0.05), the difference was not significant by transabdominal route (P>0.05).
Conclusion
Transvaginal ultrasonography seems to be superior to transabdominal sonography in
assessing the cervical length in the second trimester and for screening for spontaneous
preterm delivery. (Rawal Med J 2009;34: ).

Key words: Cervical length, transvaginal sonography, transabdominal sonography.