discrepancy in uterine size
DESCRIPTION
A tutorial on concepts related to when the uterine size shows a discrepancy with gestational datesTRANSCRIPT
DISCREPANCY IN UTERINE SIZE
An understanding of the issues involved when a uterus doesn’t correspond to its gestational age
Associate Professor Dr Hanifullah Khan
To understand the definitions involved
To understand the implications of this
situation
The important points to consider
Objectives
Discrepancy – what is it?When the uterine size does not correspond to the expected gestation
May be larger or smaller
Objective measurement - > 2 cm variation with symphysiofundal height (SFH)
Implications of this situationImplications of this situation
Has there been a mistake
in calculatin
g gestation
?
Has there been a mistake
in calculatin
g gestation
?
Is there an underlying problem causing
this discrepanc
y?
Is there an underlying problem causing
this discrepanc
y?
Is there a problem with the mother?
Is there a problem with the mother?
Is the fetus at risk?•If so, when do we deliver it?
Is the fetus at risk?•If so, when do we deliver it?
Points to consider
The patient has been found to have a gestation which does not correspond to calculations.
This may be a feature of an underlying problem
The problem may be related to the mother, fetus or placenta
It is our job to determine the underlying cause of this problem
Dates
Be absolutely positiveThe mother remembers the exact LMP (1st day)
The periods have been regular
The onset of pregnancy symptoms & quickening correspond to the dates
That an early pregnancy ultrasound (if done), confirmed the dates
Subsequent antenatal check ups have noted previous corresponding growth of uterus
In all cases, always begin by confirming
the dates
Remember, an early pregnancy ultrasound scan is the definitive
decider of dates
9
IUGR
Intrauterine growth restriction or Fetal growth restriction
Leads to uterus < dates A manifestation of underlying problem Maternal, fetal or placental Most commonly caused by placental insufficiency
(unknown cause), hypertensive disease, maternal disease, fetal anomaly
Most non-fetal causes lead to asymmetrical FGR (the so-called head-sparing effect)
Fetal Growth RestrictionLeads to long term problems
The left ear
Big baby• If fetal macrosomia is
the cause in an uterus > dates, it is most often a consequence of gestational diabetes
• GDM can also lead to polyhydramnios on its own
• It is mandatory to look hard for GDM in such cases
13
Macrosomia
14
Fetal anomalies
Any discrepancy in uterine size must lead to an extensive search for fetal anomalies
15
Multiples
Any large uterus may be caused by a multiple pregnancy There may be more
than one
See for yourself
16
The diagnosis of SGA
A constitutionally small fetus is a diagnosis of exclusion This is the last diagnosis in your list of differentials
Always rule out disease before you can say its normal
These fetuses display linear growth despite being small
Usually, the mother is also small (this is logical)
Summary
18
Discrepancy in uterine size
This denotes a uterine size not corresponding to gestational age
It may be a sign of an underlying problem
This problem could be of maternal, fetal or placental origin
One common cause is wrong dates
Rule out disease before diagnosing a constitutionally small fetus
THE ENDTHE END Thank You Very Much