Study design and patient selection
The current study was designed retrospectively between January 1, 2019
and December 31, 2021 in a single tertiary center. A
five-hundred-sixty-three pregnant women who decided to terminate
pregnancy were included in the study. This study was undertaken with the
Institutional Review Board’s approval (Approval number: 1105085). All of
the patients included in the study were below the 34th gestational week
and were evaluated by dividing them into four groups. Group 1 (G1)
consists of patients below 23 6/7 weeks of gestation without a prior
cesarean section (C/S), and group 2 (G2) consists of patients below 23
6/7 weeks of gestation with at least one prior C/S. Group 3 (G3)
consists of patients between 24-34 weeks of gestation without a prior
C/S, and group 4 (G4) consists of patients between 24-34 weeks of
gestation with at least one prior C/S. Gx and Gy refer to G1-2 and G3-4,
respectively (Table 2 and 3).
Among the dates specified in the study, cases with a fetal anomaly
incompatible with life (prenatally diagnosed with aneuploidy,
microdeletion/duplication syndromes, severe or lethal fetal structural
anomalies diagnosed with ultrasound were included), cases who were below
34 weeks of gestation and whose pregnancy was terminated due to
intrauterine demise (IUD), missed abortion or other reasons (preterm
premature rupture of membranes below 22 weeks of gestation) were
included. The cases at 34 weeks of gestation and above, the cases with a
history of non-C/S uterine surgery, pregnancies terminated by methods
other than vaginal misoprostol as a first-line treatment, the cases with
contraindication for misoprostol use and the cases who underwent
elective hysterotomy as a first-line treatment due to prior C/S history
were excluded from the study. In all cases above 22 0/7 weeks of
gestation, feticide with fetal intracardiac KCl injection was
administered before termination of pregnancy (ToP). All of the patients
was followed up to the hospital as inpatient and discharged after 24
hours if vaginal delivery had been occured and 48 hours if elective
hysterotomy had done. Before start of treatment, treatment-related
informed consent was obtained from all patients.
The treatment protocol was defined as follows in cases which ToP is
planned: In patients without a history of prior (C/S) below 23 6/7 weeks
of gestation, 400 mcg misoprostol vaginally was given as a loading dose,
the subsequent doses were given 200 mcg vaginally in every 4 hours, a
maximum dose is 1400 mcg (G1). Above 24 0/7 weeks of gestation, 200 mcg
misoprostol vaginally was administered as a loading dose, the subsequent
vaginal doses are administered as 100 mcg in every 4 hours, a maximum
dose is 700 mcg (G3). If the patient has at least one or more prior C/S
history, the doses which are previously described were halved below (G2)
and above the 24th gestational week (G4) (a maximum dose is 700 mcg and
350 mcg, respectively). When the abortion or delivery did not occur
after first regimen, patients were rested for 12 hours and the same
regimen was repeated once more. When a method used after the second
failured (vaginal misoprostol regimen, this was named as more than one
(>1) ToP procedure. Sublingual misoprostol administration,
cervical ripening balloon or oxytocin induction were chosen based on
cervical assesment in cases where vaginal delivery/abortion did not
occur following the second failured vaginal misoprostol regimen. If
there was a prior C/S history, hysterotomy was discussed with the
patient after two failured vaginal misoprostol regimens. The primary
outcome was the success rate of ToP by vaginal delivery after two LD
vaginal misoprostol regimen (single method). None of the patients in the
current study had a contraindication for prostaglandin use.