None of the current classifications
(Wigglesworth, Aberdeen, Fetal and infant) identify
those stillborn babies that are growth restricted.
They seek to determine cause, which is often not possible.
Growth restriction is not a cause of death but may
represent an underlying placental insufficiency resulting
in fetal demise. Failure to detect and to act on growth
restriction was frequently cited in both the 1in 10
and
the Euronatal enquiries as suboptimal care.
The Aberdeen classification does divide unexplained
deaths into those greater than or equal to 2.5kg and
those less than 2.5kg. However this does not distinguish
between those babies that are constitutionally small
and those that are truly growth restricted and have
failed to reach their growth potential. It is possible
to customise a baby’s weight according to the physiological
variables that affect growth potential; maternal height,
weight, parity and ethnic group ( 1).
This identifies those babies that are truly at risk
from poor outcome (2).
The Institute is proposing an alternative classification
system ReCoDe (3)
that identifies the most relevant factor at the time
of death rather than cause of death, and includes fetal
growth restriction as defined by customised standards.
Using this system the CESDI administrators at the perinatal
institute have classified the first 200 stillbirths
in the West Midlands for 2001.
By the Wigglesworth classification 70% were “unexplained”
Of these 49% remained unexplained on all classification
systems – however if reclassified by ReCoDe 61% of
these were due to IUGR leaving only 15% unexplained
in total.
This is useful when counselling couples after a stillbirth
but also suggests that If we can identify
growth restriction and act on it in time, these stillbirths
may be avoided.
References
1. Gardosi J, Chang A, Kalyan B, Sahota D, Symonds
EM. Customised antenatal growth charts. Lancet 1992;
339:283-287.
2. Claussen B, Gardosi J, Frances A, Cnattingius
S. Perinatal outcome in SGA births defined by customised
versus population-based birthweight standards. Br J
Obstet Gynaecol. 2001; 108:830-834.
3.Gardosi J, ReCoDe. Br MFM Society 2001.
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