ObjectivesTo investigate the effectiveness of routine ultrasonography in the third trimester in reducing adverse perinatal outcomes in low risk pregnancies compared with usual care and the effect of this policy on maternal outcomes and obstetric interventions.DesignPragmatic, multicentre, stepped wedge cluster randomised trial.Setting60 midwifery practices in the Netherlands.Participants13 046 women aged 16 years or older with a low risk singleton pregnancy.Interventions60 midwifery practices offered usual care (serial fundal height measurements with clinically indicated ultrasonography). After 3, 7, and 10 months, a third of the practices were randomised to the intervention strategy. As well as receiving usual care, women in the intervention strategy were offered two routine biometry scans at 28-30 and 34-36 weeks’ gestation. The same multidisciplinary protocol for detecting and managing fetal growth restriction was used in both strategies.Main outcome measuresThe primary outcome measure was a composite of severe adverse perinatal outcomes: perinatal death, Apgar score <4, impaired consciousness, asphyxia, seizures, assisted ventilation, septicaemia, meningitis, bronchopulmonary dysplasia, intraventricular haemorrhage, periventricular leucomalacia, or necrotising enterocolitis. Secondary outcomes were two composite measures of severe maternal morbidity, and spontaneous labour and birth.ResultsBetween 1 February 2015 and 29 February 2016, 60 midwifery practices enrolled 13 520 women in mid-pregnancy (mean 22.8 (SD 2.4) weeks’ gestation). 13 046 women (intervention n=7067, usual care n=5979) with data based on the national Dutch perinatal registry or hospital records were included in the analyses. Small for gestational age at birth was significantly more often detected in the intervention group than in the usual care group (179 of 556 (32%) v 78 of 407 (19%), P<0.001). The incidence of severe adverse perinatal outcomes was 1.7% (n=118) for the intervention strategy and 1.8% (n=106) for usual care. After adjustment for confounders, the difference between the groups was not significant (odds ratio 0.88, 95% confidence interval 0.70 to 1.20). The intervention strategy showed a higher incidence of induction of labour (1.16, 1.04 to 1.30) and a lower incidence of augmentation of labour (0.78, 0.71 to 0.85). Maternal outcomes and other obstetric interventions did not differ between the strategies.ConclusionIn low risk pregnancies, routine ultrasonography in the third trimester along with clinically indicated ultrasonography was associated with higher antenatal detection of small for gestational age fetuses but not with a reduced incidence of severe adverse perinatal outcomes compared with usual care alone. The findings do not support routine ultrasonography in the third trimester for low risk pregnancies.Trial registrationNetherlands Trial Register NTR4367.

BackgroundIntrauterine growth retardation (IUGR) is a major risk factor for perinatal mortality and morbidity. Thus, there is a compelling need to introduce sensitive measures to detect IUGR fetuses. Routine third trimester ultrasonography is increasingly used to detect IUGR. However, we lack evidence for its clinical effectiveness and cost-effectiveness and information on ethical considerations of additional third trimester ultrasonography. This nationwide stepped wedge cluster-randomized trial examines the (cost-)effectiveness of routine third trimester ultrasonography in reducing severe adverse perinatal outcome through subsequent protocolized management.MethodsFor this trial, 15,000 women with a singleton pregnancy receiving care in 60 participating primary care midwifery practices will be included at 22 weeks of gestation. In the intervention (n = 7,500) and control group (n = 7,500) fetal growth will be monitored by serial fundal height assessments. All practices will start offering the control condition (ultrasonography based on medical indication). Every three months, 20 practices will be randomized to the intervention condition, i.e. apart from ultrasonography if indicated, two routine ultrasound examinations will be performed (at 28–30 weeks and 34–36 weeks). If IUGR is suspected, both groups will receive subsequent clinical management as described in the IRIS study protocol that will be developed before the start of the trial.The primary dichotomous clinical composite outcome is ‘severe adverse perinatal outcome’ up to 7 days after birth, including: perinatal death; Apgar score <4 at 5 minutes after birth; impaired consciousness; need for assisted ventilation for more than 24 h; asphyxia; septicemia; meningitis; bronchopulmonary dysplasia; intraventricular hemorrhage; cystic periventricular leukomalacia; neonatal seizures or necrotizing enterocolitis. For the economic evaluation, costs will be measured from a societal perspective. Quality of life will be measured using the EQ-5D-5 L to enable calculation of QALYs. Cost-effectiveness and cost-utility analyses will be performed. In a qualitative sub-study (using diary notes from 32 women for 9 months, at least 10 individual interviews and 2 focus group studies) we will explore ethical considerations of additional ultrasonography and how to deal with them.DiscussionThe results of this trial will assist healthcare providers and policymakers in making an evidence-based decision about whether or not introducing routine third trimester ultrasonography.Trial registration NTR4367, 21 March 2014.

BackgroundScreening for, diagnosis and management of intrauterine growth restriction (IUGR) is often performed in multidisciplinary collaboration. However, variation in screening methods, diagnosis and management of IUGR may lead to confusion. In the Netherlands two monodisciplinary guidelines on IUGR do not fully align. To facilitate effective collaboration between different professionals in perinatal care, we undertook a Delphi study with uniform recommendations as our primary result, focusing on issues that are not aligned or for which specifications are lacking in the current guidelines.MethodsWe conducted a Delphi study in three rounds. A purposively sampled selection of 56 panellists participated: 27 representing midwife-led care and 29 obstetrician-led care. Consensus was defined as agreement between the professional groups on the same answer and among at least 70% of the panellists within groups.ResultsPer round 51 or 52 (91% - 93%) panellists responded. This has led to consensus on 27 issues, leading to four consensus based recommendations on screening for IUGR in midwife-led care and eight consensus based recommendations on diagnosis and eight on management in obstetrician-led care. The multidisciplinary project group decided on four additional recommendations as no consensus was reached by the panel. No recommendations could be made about induction of labour versus expectant monitoring, nor about the choice for a primary caesarean section.ConclusionsWe reached consensus on recommendations for care for IUGR within a multidisciplinary panel. These will be implemented in a study on the effectiveness and cost-effectiveness of routine third trimester ultrasound for monitoring fetal growth. Research is needed to evaluate the effects of implementation of these recommendations on perinatal outcomes.Trial registration NTR4367.

What are the novel findings of this work?Even small errors in the first-trimester measurement of crown-rump length (CRL) significantly affect secondand third-trimester estimated fetal weight (EFW). A measurement error of −2 mm in first-trimester CRL shifts an EFW on the 10 th percentile at the 20-week scan to around the 20 th percentile. A measurement error of + 2 mm shifts an EFW on the 10 th percentile to around the 5 th percentile. What are the clinical implications of this work?Published data suggest that CRL measurement errors of 2 mm or more are common in clinical practice. Misclassification as small-, appropriate-or large-for-gestational age will commonly occur and affect clinical assessment, patient management and research results. Thus, there is a need to increase awareness of the importance of correct CRL measurement and to reduce measurement error variation through standardization and quality control.

Routine third trimester ultrasonography is increasingly used to screen for fetal growth restriction. However, evidence regarding its cost-effectiveness is lacking. We aimed to evaluate the cost-effectiveness of routine third trimester ultrasonography to reduce adverse perinatal outcomes compared to usual care (selective ultrasonography). An economic evaluation alongside a stepped-wedge cluster-randomized trial was conducted. Via 60 midwifery practices 12,974 Dutch women aged ≥16 years with low-risk pregnancies were enrolled at 22.8 (SD = 2.4) weeks’ gestation. All practices provided usual care. At 3, 7, and 10 months a third of the practices were randomized to the intervention strategy providing routine ultrasonography at 28–30 and 34–36 weeks’ gestation and usual care. The primary clinical outcome was a dichotomous composite measure of 12 severe adverse perinatal outcomes (SAPO) up to one week postpartum. Information on perinatal care and societal costs was derived from Netherlands Perinatal Registry, hospital records and a survey. Cost-effectiveness analyses revealed no significant differences in SAPO and healthcare and societal costs between the intervention strategy (n = 7026) and usual care (n = 5948). Cost-effectiveness acceptability curves showed that the probability of cost-effectiveness was never higher than 0.6 for all possible ceiling ratios. Adding routine third trimester ultrasonography to usual care is not cost-effective in reducing SAPO.