Study population
In 2020, a total of 6046 women were booked for delivery in our hospital
and 1868 low-risk singleton deliveries at 40 0/7-41 6/7 weeks were
included in the study. Of these, 299 pregnancies were excluded based on
the following factors: elected caesarean delivery (n = 295), VBAC (n =
3) and partial data loss (n = 1). Ultimately, a total of 1569
pregnancies met the inclusion criteria. Among them, 1107 (71%)
pregnancies delivered at 40 0/7-40 6/7 weeks and 462 (29%) delivered at
41 0/7-41 6/7 weeks (Fig. 1).
Maternal characteristics in the study groups are compared in Table 1. A
total of 1262 (approximately 80%) were nulliparous, and 73
(<5%) were assisted reproductive pregnancies. Approximately
60% of women had complications, including anaemia, hypothyroidism,
diabetes and other unusual complications. Statistical significance was
not observed in the cases of anaemia or hypothyroidism between the two
groups. The risk of premature rupture
of membranes (PROM) in the full-term group was significantly higher than
that in the late-term group (22% versus 12%, P<0.001). The
prevalence rate of gestational diabetes mellitus (GDM) in the full-term
group was significantly higher than that in the late-term group (16%
versus 8%, P<0.001).
Different modes of labour are compared in Table 2. The spontaneous
labour rate was significantly higher than that in the late-term group
(54% versus 20%, P<0.001). The full-term group was lower
than the late-term group in terms of the rate of induction of balloon
catheter combined with oxytocin (BCCO) (9% versus 46%,
P<0.001), the rate of oxytocin induction (22% versus 27%,
P=0.012) and artificial rupture of membrane (AROM) induction (21%
versus 31%, P<0.001). The Bishop score of parturients with
BCCO induction was not statistically significant (P=0.055). However, the
late-term group had a higher final vaginal delivery rate of BCCO (88%
versus 79%, P=0.049) and AROM (83% versus 71%, P=0.006). Significant
differences were not observed in the vaginal delivery rate of oxytocin
induction (80% versus 76%, P=0.431).