Cervical Length Screening in Asymptomatic Women at High Risk and Low Risk for Spontaneous Preterm Birth

Abstract

Cervical length (CL) screening should be offered to singletons because there are interventions for those with a short CL. A transvaginal ultrasound (TVU) is the ''gold standard'' for CL. In singletons with prior spontaneous preterm birth, serial TVU CL screening isrecommended between16and236/7weeks. Universal TVU CL screening between 18 and 24 weeks may be considered for low-risk singletons with the administration of vaginal progesterone for TVU CLr20 mm; alternatively, transabdominal ultrasound CL screening may be considered with reflux to TVU CL screening for a transabdominal ultrasound CL<35 mm or inadequate visualization. CL screening is not recommended in multiples.

Transvaginal sonographic cervical length in first and second trimesters in a low‐risk population: a prospective study

“…The lower proportion of women with short secondtrimester CL in this study is, however, in accordance with recent large studies on screening programs at 18-23 weeks [26][27][28] . In a low-risk population of 1569 women, 1.1% had CL < 20 mm and there was no difference in risk of spontaneous PTD between women undergoing and not undergoing screening 28 . Likewise, Miller et al 27 reported a 0.9% incidence of CL ≤ 25 mm among 18 250 women at 20 weeks.…”

“…Our data support the literature suggesting that universal CL screening in the second trimester may not be as cost-effective as believed previously, as it is highly dependent on the proportion of short CL and the rate of spontaneous PTD [26][27][28]32 . In our population, if CL screening was implemented at the 19-21-week anomaly scan, the NNS to prevent one spontaneous PTD < 34 weeks was more than 1500 women.…”

“…reported a 0.9% incidence of CL ≤ 25 mm among 18 250 women at 20 weeks. Both studies excluded women with a history of PTD. In an unselected single‐center population of 10 871 women at 17–23 weeks' gestation, the prevalence of CL ≤ 25 mm and ≤ 20 mm were 2.0% and 1.2%, respectively, i.e.…”

Modern Ultrasonographic Techniques in Diagnosing Patients with a High Risk for Preterm Delivery

“…In low-risk pregnant women, mean CL at 14-30 weeks of gestation varies from 35 to 4mm, with the 10th percentile being 25mm and 90th percentile being 50mm [8]. In asymptomatic women after 30 gestational weeks, the cervix physiologically shortens and CL less than 25mm does not indicate preterm labor [9]. It seems that initial screening for preterm delivery should start between 18 and 22 weeks of gestation, because in most women who deliver before 37 weeks a short cervix is detected at that time [8].…”

Diagnóstico y prevención del parto pretermino. Una actualización de la literatura

“…Por tanto, surge la imperiosa necesidad de desarrollar estrategias efectivas para tamizaje y prevención de parto pretérmino en la población de mujeres embarazadas, con o sin factores de riesgo (1, 2). En la actualidad se considera que un cuello uterino corto en el segundo trimestre es nuestro mejor predictor de síndrome de parto pretérmino (10,11). Aunque el tratamiento de cérvix corto sigue siendo controvertido a pesar de más de 600 publicaciones en las últimas 2 décadas sobre la relación entre síndrome de parto pretérmino, cuello uterino corto y las intervenciones propuestas (5).…”