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This is a plain English summary of an original research article. The views expressed are those of the author(s) and reviewer(s) at the time of publication.
A care package to increase awareness of fetal movements, and allow identification and delivery of high-risk babies, did not reduce the risk of stillbirth.
The incidence of stillbirth varies across high-income countries suggesting that many could be preventable. The AFFIRM trial is the largest to date to assess whether interventions that increase awareness of fetal movements can reduce risk of stillbirth. The trial involved 33 hospitals in the UK and Ireland who implemented the care package at different intervals. A total of 409,175 pregnancies were included. There were four stillbirths per 1,000 births during both the control and intervention periods. The intervention was also associated with increased rates of induction of labour and caesarean section and longer stays for babies in neonatal units.
The evidence does not support this package of policies to increase awareness of fetal movements as an effective way to reduce the incidence of stillbirths.
Why was this study needed?
Stillbirth is defined as a baby born dead after 24 completed weeks of pregnancy (gestation). It occurs in approximately 1 in every 200 births in England. In most cases, there are no known pregnancy risk factors or fetal abnormalities. A reduction or sudden change in fetal movements is thought to be an important clinical sign. Studies that have used ultrasound to assess fetal wellbeing have observed an association between reduced movements and poor perinatal outcomes. In one study, 55% of women who experienced stillbirth had reported reduced fetal movements.
However, there has been no good evidence that raised awareness of fetal movements is effective in preventing stillbirth. This cluster-randomised trial assessed a care package to raise awareness of fetal movements using a stepped-wedge design, where all participating hospitals would introduce the intervention at set intervals.
What did this study do?
The AFFIRM trial involved 33 maternity hospitals in the UK and Ireland, of 37 invited to participate. It started in January 2014 when hospitals were randomised to one of nine implementation dates at three-month intervals. Each hospital had three observation periods: the control period, a two-month ‘washout’ period after the date was given, and the intervention period. Trial completion was December 2016. It included 409,175 women.
The intervention included an e-learning education package for clinical staff and a leaflet given to pregnant woman around 20 weeks’ gestation. A management plan for identification and delivery of high-risk babies was put in place for mothers reporting reduced fetal movements after 24 weeks.
The trial was unable to detect a reduction in stillbirth incidence of less than 30% as the outcome is rare. Only 60% of centres adhered to all intervention components.
What did it find?
- The incidence of stillbirth was 4.40 per 1,000 births during the control period and 4.06 per 1,000 births during the intervention period (adjusted odds ratio [aOR] 0.90, 95% confidence interval [CI] 0.75 to 1.07, adjusted for maternal age and multiple pregnancies). The absolute difference was 5 fewer stillbirths per 10,000 births (95% CI 11 fewer to 3 more).
- There was no difference in effect when analysing according to gestational age at stillbirth, or when looking at perinatal mortality.
- Of secondary outcomes, spontaneous vaginal delivery was slightly less common during the intervention (57.4%) than control (59.8%) periods (aOR 0.90, 95% CI 0.88 to 0.92). Induction of labour was more common (40.7% vs 35.8%; aOR 1.05, 95% CI 1.02 to 1.08) and more babies were delivered by caesarean section (28.3% vs 25.5%; aOR 1.09, 95% CI 1.06 to 1.12).
- Slightly more babies were admitted to the neonatal unit for more than 48 hours during the intervention (6.7% vs 6.2%; aOR 1.12, 95% CI 1.06 to 1.18), but there was no difference in the number of babies admitted, overall (10.1% during each period).
- Fewer babies were born small for gestational age during the intervention period (1.5% vs 2.0%; aOR 0.86, 95% CI 0.78 to 0.95). The authors suggest this may indicate that the intervention was effective in supporting identification and timely delivery of babies with placental insufficiency who may be at risk of stillbirth.
What does current guidance say on this issue?
NICE antenatal care guidelines (updated December 2018) recommend that routine formal fetal movement counting should not be offered.
The Royal College of Obstetricians and Gynaecologists (RCOG) guidelines on reduced fetal movements (published 2011) stated that there is insufficient evidence to recommend formal fetal movement counting using specified alarm limits. RCOG advises that instructing women to monitor fetal movements may be associated with increased maternal anxiety. However, women are advised to be aware of their baby’s movement patterns and to contact their maternity unit if they are concerned about reduced or changed movements after 28 weeks’ gestation.
What are the implications?
This study supports current guidelines and provides no evidence that policy change to increase clinician and parent awareness of fetal movements would reduce the incidence of stillbirth. Raised awareness and setting of alert limits may, however, result in fewer spontaneous births and more interventional deliveries.
The possibility that increasing fetal movement awareness may give a small reduction in stillbirth incidence can’t be excluded, because these events are so rare. It’s also difficult to assess whether the intervention resulted in behaviour change among healthcare providers or mothers. Another limitation is that over a third of hospitals taking part did not comply with all elements of the care package, including checking by ultrasound.
However, this large study may be the best evidence that can be obtained in the trial context and supports continued attempts to look elsewhere to find interventions that work.
Citation and Funding
Norman JE, Heazell AE, Rodriguez A et al. Awareness of fetal movements and care package to reduce fetal mortality (AFFIRM): a stepped wedge, cluster-randomised trial. Lancet. 2018;392:1629-38.
This study funded by the Chief Scientist Office, Scottish Government, Tommy’s, and Sands. Some infrastructure support was provided by the NIHR.
Bibliography
NHS website. Overview: Stillbirth. London: Department of Health and Social Care; 2018.
NICE. Antenatal care for uncomplicated pregnancies. CG62. London: National Institute for Health and Care Excellence; 2008, updated December 2018.
RCOG. Reduced fetal movements. London: Royal College of Obstetricians and Gynaecologists; 2011.
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