Value of routine ultrasound examination at 35–37 weeks' gestation in diagnosis of non‐cephalic presentation

Abstract

CONTRIBUTIONWhat are the novel findings of this work? This study reports the incidence of non-cephalic presentation at a routine ultrasound examination at 35 + 0 to 36 + 6 weeks' gestation and subsequent management of such pregnancies. What are the clinical implications of this work?Routine ultrasound examination at 35 + 0 to 36 + 6 weeks' gestation detects non-cephalic presentation in about 5% of pregnancies. Such diagnosis could potentially improve pregnancy outcome by preventing unexpected abnormal presentation in labor and, through external cephalic version, reducing the incidence of non-cephalic presentation. ABSTRACTObjective Undiagnosed non-cephalic presentation in labor carries increased risks for both the mother and baby. Routine pregnancy care based on maternal abdominal palpation fails to detect the majority of cases of non-cephalic presentation. The aim of this study was to report the incidence of non-cephalic presentation at a routine scan at 35 + 0 to 36 + 6 weeks' gestation and the subsequent management of such pregnancies. MethodsThis was a retrospective analysis of prospectively collected data in 45 847 singleton pregnancies that had undergone routine ultrasound examination at 35 + 0 to 36 + 6 weeks' gestation. Patients with breech or transverse/oblique presentation were divided into two groups; first, those who would have elective Cesarean section for fetal or maternal indications other than the abnormal presentation, and, second, those who would potentially require external cephalic version (ECV). The latter group was reassessed after 1-2 weeks and, if there was persistence of abnormal presentation, the parents were offered the option of ECV or elective Cesarean section at 38-40 weeks' gestation. Multivariable logistic regression analysis was carried out to determine which of the factors from maternal and pregnancy characteristics provided a significant contribution in the prediction of, first, non-cephalic presentation at the 35 + 0 to 36 + 6-week scan, second, successful ECV from non-cephalic to cephalic presentation, and, third, spontaneous rotation from non-cephalic to cephalic presentation that persisted until delivery.Results First, at 35 + 0 to 36+ 6 weeks, the fetal presentation was cephalic in 43 416 (94.7%) pregnancies, breech in 1987 (4.3%) and transverse or oblique in 444 (1.0%). Second, multivariable analysis demonstrated that the risk of non-cephalic presentation increased with increasing maternal age and weight, decreasing height and earlier gestational age at scan, was higher in the presence of placenta previa, oligohydramnios or polyhydramnios and in nulliparous than parous women, and was lower in women of South Asian or mixed racial origin than in white women. Third, 22% of cases of non-cephalic presentation were not eligible for ECV because of planned Cesarean section for indications other than the malpresentation. Fourth, of those eligible for ECV, only 48.5% (646/1332) agreed to the procedure, which was successful in 39.0% (252/646) of cases. Fifth, the chance of successful...

Ophthalmic artery Doppler in prediction of pre‐eclampsia at 35–37 weeks' gestation

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FIGO (International Federation of Gynecology and Obstetrics) initiative on fetal growth: Best practice advice for screening, diagnosis, and management of fetal growth restriction

“…at a 10% false-positive rate. 183 There are many conceptual explanations to support thirdtrimester ultrasound as it can assist in the diagnosis of clinically significant findings other than FGR, including fetal malpresentation, 184 disorders of amniotic fluid, and fetal anomalies, 185,186 especially when combined with Doppler measurements and biochemical markers. 95,[187][188][189] However, there is no evidence that this information improves outcomes when performed routinely in lowrisk pregnancies.…”

Effect of routine first‐trimester combined screening for pre‐eclampsia on small‐for‐gestational‐age birth: secondary interrupted time series analysis

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