Clinical study
A single-centre, RCT was conducted from January 2017 to July 2021) at
the largest tertiary care centre in South Australia (Women’s and
Children’s Hospital , North Adelaide) (Australian Clinical Trial
register number
ACTRN12615001308583;
Womens and Childrens Health Network Human Research Ethics Committee
approval (HREC/14/WCHN/145). Eligibility for the trial included: being
aged 18 years or older with a singleton pregnancy; a fetus in cephalic
presentation; a gestational age >36weeks and an indication
for CEFM based on RANZCOG guidelines(9). Women were randomly allocated
(1:1 ratio with stratification for parity) to monitoring either by
CTG+STan or CTG alone(. The primary hypothesis was that the proportion
of EmCS for women on CTG+STan is not equal to that for women on CTG
monitoring alone. Our secondary hypotheses included that CTG+STan
monitoring is cost-effective compared to CTG alone (8).
For women assigned to CTG+STan, a fetal scalp electrode (FSE) was
applied to the fetal head and connected to a STAN® fetal heart monitor
(STAN, Neoventa Medical, Mölndal, Sweden)(10), which allowed both
conventional CTG interpretation and ST analysis of the fetal ECG.
Further clinical management was made using the STan clinical guidelines
[STAN2007 CTG classification system] (11), in addition to CTG
classification and interpretation according to the RANZCOG clinical
guidelines (9). In women assigned to CTG alone, either an external
doppler transducer was utilised, or a FSE was applied to the fetal head
and a conventional fetal heart rate monitor (Philips or Neoventa) was
used. The CTG was classified and interpreted according to the RANZCOG
clinical guidelines (9) Clinical decisions were based on overall
clinical assessment combined with STan and/or CTG interpretation, as
described in further detail in the study protocol (8).