Impact of medication correction of labor weakness on obstetrical complications and newborn status

Abstract

Objectives: To analyze the impact of medical correction of labor weakness with oxytocin on obstetric and newborn complications.Materials and methods. 100 cases of childbirth with weakness of labor activity and medical correction with oxytocin (main group) and 50 cases of childbirth without weakness of labor activity (control group) were analyzed. The analysis included pregnancy and childbirth histories of mothers aged 20–32 years with a gestation period of 37– 41 weeks with uncomplicated pregnancies, without significant somatic and obstetric-gynecological pathology, who gave birth in the Perinatal Center of Kyiv during the last 3 years.Depending on the method of delivery, the women of the main group were divided into 3 subgroups: Iа – natural vaginal, spontaneous delivery (n = 60), Ib – operative vaginal delivery using a vacuum extractor (n = 22), Іc – delivery by cesarean section (n = 18).The following factors were studied in each group: assessment of newborns status according to the Apgar scale at the 1st and 5th minutes, pH level of the umbilical cord blood, frequency of fetal distress based on cardiotocography (Fischer score < 6 points), duration of labor induction, color of the amniotic fluid.Results. The average duration of labor was the largest in the subgroup of spontaneous vaginal deliveries, the smallest in the subgroup of cesarean section. In subgroup Ib in 14 (63.6%) cases indications for the vacuum extractor were signs of fetal distress and only in 8 (36.4%) cases – weakness of labor activity.In subgroup Ia compared to subgroup Ic, there was a longer average duration of labor and higher percentage of deliveries with meconium-stained waters (28.3%), higher frequency of neonatal acidemia (16.7%) and the birth of children with an Apgar score at the 5th minute ≤ 6 points (8.4%). In subgroup Ic compared to subgroup Ia, there was a higher value of cases of Fischer score < 6 points (50%), the duration of labor reinforcement for more than 4 hours (44.5%), more cases of asphyxia (44.5%), and the birth of children with an Apgar score at the 1st minute ≤ 6 points (38.9%). Indications for caesarean section in subgroup Ic in 50% of cases were signs of fetal distress, in 38.9% – weakness of labor activity which was not associated with medication, in 11.1% – a clinically narrow pelvis.In all groups there was a relationship between the duration of labor induction and the condition of the newborn (the frequency of asphyxia of newborns was higher when the infusion of oxytocin lasted more than 4 hours).In subgroup Ib fetal distress was the indication for urgent delivery in 63.6% of cases, and in subgroup Iс it was 50%. This indicates signs of a mediated negative effect of exogenous oxytocin on the fetus during childbirth. The newborns condition, according to the studied criteria, was worse in the groups with labor reinforcement compared to the control group, regardless of the method of delivery.Conclusions. The use of oxytocin during childbirth can have a negative effect on the fetus, which increases the frequency of operative vaginal deliveries and cesarean sections and, as a result, is a risk factor for complications in the postpartum period. There is a correlation between duration of oxytocin injection and condition of the newborn.