In the realm of healthcare, where precision and consistency are paramount, the recent study on fetal growth charts has exposed a critical flaw that is not only costing lives but also highlighting the stark reality of healthcare disparities. The research, led by Jason Gardosi and published in the BMJ, delves into the inconsistent use of fetal growth charts across England, revealing a stark disparity in the identification of small for gestational age (SGA) babies. This issue is not merely a statistical quirk; it's a life-and-death matter.
The study, examining data on 3.2 million births between 2015 and 2025, found that the proportion of babies identified as SGA varied widely depending on the chart used, ranging from 5.5% to 18.7%. This means a baby flagged as dangerously small in one trust might pass through an identical pregnancy in a neighbouring trust and never be flagged at all. The reason lies in the charts themselves, which are one-size-fits-all measures that cannot be adjusted for maternal characteristics. This is where the customized GROW chart, produced by the Perinatal Institute, comes into play, offering a more nuanced approach by factoring in maternal height, weight, parity, and ethnic origin.
The implications of this inconsistency are profound. A baby who is constitutionally small because of their mother's profile might be flagged as at risk on a generic chart and monitored unnecessarily, while a baby who is pathologically small for its own mother's profile may be waved through as normal. The latter error is the more insidious one, as it can lead to stillbirth. This raises a deeper question: how can we ensure that every baby, regardless of where they are born, has an equal chance of being correctly identified as at risk?
The response from regulators has been partial, with NHS Trusts using INTERGROWTH EFW charts instructed to stop by March 2026. However, this move falls short of a comprehensive solution. The absence of a new national review of the evidence comparing available growth charts and the lack of a specific alternative recommended leaves the postcode lottery in place under a different label. This is not the first time fetal growth measurement has surfaced as a named failure, with previous inquiries calling for standardisation and an independent study of the accuracy of different growth charts.
The BMJ authors advocate for a coordinated national programme with real-time oversight of quality and safety in this area of maternity care. They argue that individual trusts encounter rare but catastrophic outcomes too late, shaped by local protocols and practice. What is missing is a single body willing to name the chart, fund the training, and hold trusts to it. Until that happens, a baby's chance of being correctly identified as at risk will continue to depend less on their mother's pregnancy than on which hospital she happens to walk into.
This issue is not just about the charts; it's about the systemic failure to address a critical healthcare disparity. It's a call to action for a more equitable and consistent healthcare system, where every baby, regardless of their birthplace, has an equal chance of being correctly identified as at risk and receiving the necessary care. The time for action is now, and the stakes could not be higher.
