The predictive capacity of uterine artery Doppler for preterm birth - a cohort study

Introduction: Mid‐trimester uterine artery resistance measured with Doppler sonography is predictive for iatrogenic preterm birth. In view of the emerging association between hypertensive disease in pregnancy and spontaneous preterm birth, we hypothesized that uterine artery resistance could also predict spontaneous preterm birth. Material and methods: We performed a cohort study of women with singleton pregnancies. Uterine artery resistance was routinely measured at the 18‐22 weeks anomaly scan. Pregnancies complicated by congenital anomalies or intrauterine fetal death were excluded. We analyzed if the waveform of the uterine artery (no notch, unilateral notch or bilateral notch) was predictive for spontaneous and iatrogenic preterm birth, defined as delivery before 37 weeks of gestation. Furthermore, we assessed whether the uterine artery pulsatility index was associated with the risk of preterm birth. Results: Between January 2009 and December 2016 we collected uterine Doppler indices and relevant outcome data in 4521 women. Mean gestational age at measurement was 19+6 weeks. There were 137 (3.0%) women with a bilateral and 213 (4.7%) with a unilateral notch. Mean gestational age at birth was 38+6 weeks. Spontaneous and iatrogenic preterm birth rates were 5.7% and 4.9%, respectively. Mean uterine artery resistance was 1.12 in the spontaneous preterm birth group compared with 1.04 in the term group (P = 0.004). The risk of preterm birth was increased with high uterine artery resistance (OR 2.9 per unit; 95% CI 2.4‐3.9). Prevalence of spontaneous preterm birth increased from 5.5% in women without a notch in the uterine arteries to 8.0% in women with a unilateral notch and 8.0% in women with a bilateral notch. For iatrogenic preterm birth, these rates were 3.9%, 13.6% and 23.4%, respectively. Likelihood ratios for the prediction of spontaneous preterm birth were 1.6 (95% CI 1.0‐2.6) and 1.9 (95% CI 1.0‐3.5) for unilateral and bilateral notches, respectively, and for iatrogenic preterm birth they were 3.6 (95% CI 2.5‐5.2) and 6.8 (95% CI 4.7‐9.9) for unilateral and bilateral notches, respectively. Of all women with bilateral notching, 31.4% delivered preterm. Conclusions: Mid‐trimester uterine artery resistance measured at 18‐22 weeks of gestation is a weak predictor of spontaneous preterm birth.Maud D. van Zijl, Bouchra Koullali, Ben W.J. Mol, Rosalinde J. Snijders, Brenda M. Kazemier, Eva Pajkr

Repeated cervical length measurements for the verification of short cervical length

Research into fetal development and medicin

Risk assessment and prevention of spontaneous preterm birth

Preterm birth is the most important cause of neonatal mortality and morbidity worldwide. The pathogenesis of preterm birth is complex and largely unknown. Despite extensive research, preterm birth remains relatively hard to predict and difficult to prevent. It is a major clinical and scientific challenge in the obstetric healthcare. This thesis describes various risk factors in different populations of pregnant women that contribute to the risk prediction of preterm birth. In addition, current available and potential novel preventive management strategies in women at risk for spontaneous preterm birth are discussed

Birth spacing in the United States - Towards Evidence-Based Recommendations

Introduction to the supplement

Spontaneous and iatrogenic preterm birth rates among unselected women in three consecutive pregnancies

Abstract not availableEsme I. Kamphuis, Anita C.J. Ravelli, Bouchra Koullali, Brenda Kazemier, Christianne J.M de Groot, Ben Willem J. Mo

Prevention of preterm delivery: current challenges and future prospects

Maud D van Zijl,1 Bouchra Koullali,1 Ben WJ Mol,2 Eva Pajkrt,1 Martijn A Oudijk1 1Department of Obstetrics and Gynaecology, Academic Medical Center, Amsterdam, the Netherlands; 2The Robinson Research Institute, School for Reproductive Health and Pediatrics, University of Adelaide, Adelaide, SA, Australia Abstract: Preterm birth (PTB), defined as delivery at <37 weeks of gestation, is the most important cause of neonatal morbidity and mortality. Therefore, preventing PTB is one of the main goals in obstetric care. In this review, we provide an overview of the current available literature on screening for risk factors for PTB and a summary of preventive strategies in both low-risk and high-risk women with singleton or multiple gestations. Furthermore, current challenges and future prospects on PTB are discussed. For an optimal prevention of PTB, risk stratification should be based on a combination of (maternal) risk factors, obstetric history, and screening tools. Cervical length measurements can help identify women at risk. Thereafter, preventive strategies such as progesterone, pessaries, and cerclage may help prevent PTB. Effective screening and prevention of PTB vary between the different pregnancy populations. In singleton or multiple pregnancies with a short cervix, without previous PTB, a pessary or progesterone might prevent PTB. In women with a (recurrent) PTB in the past, progesterone and a cerclage may prevent recurrence. The effect of a pessary in these high-risk women is currently being studied. A strong collaboration between doctors, patients’ organizations, pharmaceutical companies, and (international) governments is needed to reduce the morbidity and mortality as a result of spontaneous PTB. Keywords: preterm birth, prevention, risk factors, current challenges, future prospect