To demonstrate the safety of fetal delivery through placental incision in a placenta previa pregnancy.
We examined the medical records of 80 women with singleton pregnancy diagnosed with placenta previa who underwent cesarean section between May 2010 and May 2015 at the Department of Obstetrics and Gynecology, Chungbuk National University Hospital. Among the women with placenta previa, those who did not have the placenta in the uterine incision site gave birth via conventional uterine incision, while those with anterior placenta previa or had placenta attached to the uterine incision site gave birth via uterine incision plus placental incision. We compared the postoperative hemoglobin level and duration of hospital stay for the mother and newborn of the two groups.
There was no difference between the placental incision group and non-incision group in terms of preoperative and postoperative hemoglobin change, the amount of blood transfusions required by the mother, newborns with 1-min or 5-min Apgar scores below 7 points or showing signs of acidosis on umbilical cord blood gas analysis result of pH below 7.20. Moreover, neonatal hemoglobin levels did not differ between the two groups.
Fetal delivery through placental incision during cesarean section for placenta previa pregnancy does not negatively influence the prognosis of the mother or the newborn, and therefore, is considered a safe surgical technique.
Placenta previa occurs when the placenta totally or partially covers the opening of the cervix or when the placenta is attached in the vicinity of the cervix. Depending on the location of the attached placenta in relation to the uterine wall, placenta previa can be classified into anterior placenta previa and posterior placenta previa, and can be further categorized into complete, partial, marginal, and low lying placenta, according to the degree to which the placenta covers the opening of the cervix [
We examined the medical records of all pregnant women diagnosed with placenta previa who underwent cesarean section between May 2010 and May 2015 at the Department of Obstetrics and Gynecology, Chungbuk National University Hospital. This study was approved by the Institutional Review Board for Clinical Research in our institute. We compared the subjects by dividing them into two groups. For 31 cases of anterior placenta previa, and 9 cases of posterior placenta previa, in which a part of the placenta invaded into the uterine incision site and placental incision was unavoidable, the placenta was incised to deliver the newborn; these cases were allocated to the placental incision group. Forty cases of posterior placenta previa in which placental incision was not necessary were allocated to the non-incision group. Excluding placental abruption, multifetal pregnancy, and premature rupture of membranes before 30 weeks gestation, a total of 80 subjects were enrolled in the present study. We did not select patients, but incidentally the number of subjects of both groups was equal.
Lower segment transverse incision was used as a uterine incision method for all cases, regardless of the position of the placenta. Three full-time experienced clinicians performed cesarean sections on patients with anterior placenta previa who necessitated placental incision, and placental incision and fetal delivery methods were identical for all three operating surgeons. Once the placenta was exposed after incising the myometrium, the surgeon inserted his fingers between the incised sections, and penetrated through the remaining placenta and amnion to deliver the newborn. Prior to the surgery, patients received a thorough explanation of the complications that may arise from placenta previa, the risks of fetal delivery through placental incision, and hospital expertise available to the patients and guardians. All patients provided consent.
We divided the patients into the placental incision group and the non-incision group. For mothers, preoperative and postoperative hemoglobin change, presence of blood transfusion, amounts of blood transfusion, and duration of hospital stay were compared. For newborns, Apgar score, umbilical cord blood gas analysis and hemoglobin, and duration of hospital stay were compared. To determine the presence of anemia in two-day old newborns, capillary blood sampling was conducted for comparative analysis. Shapiro-Wilk normality test, Student's t-test, Mann-Whitney U-test, chi-square test, and Fisher's extract test were used for statistical analysis of the results, and
Of the total placenta previa pregnancies, the placental incision group included 40 patients and the non-incision group, 40 patients. Comparison of the placental incision group and the non-incision group revealed that age, gestational week, height, weight, body mass index, and preoperative hemoglobin level all followed normal distributions, and no statistically significant difference in clinical characteristics was observed between the two groups.
Depending on the placental incision, the frequency of mothers who received blood transfusion during or after surgery was 26 out of 40 patients in the placental incision group, and 14 out of 40 patients in the non-incision group. There was no statistical significant difference between the two groups. Of the mothers who did not receive blood transfusion in the two groups, we examined the change between hemoglobin level before surgery and 2 days after surgery. Mothers who received blood transfusion before or after surgery were excluded. The reduced hemoglobin level between the placental incision group and the non-incision group was not considered statistically significant.
The duration of hospital stay of mothers in both groups was a median of 5.5 days (range, 4 to 11 days) in the incision group and a median of 5 days (range, 4 to 9 days) in the non-incision group. Although this difference was statistically significant, it was not a clinical major difference. The frequency of cesarean hysterectomy was 7 patients in the placental incision group and 2 patients in the non-incision group. Pathology examination confirmed placenta accreta in 8 of these 9 patients (
The reduced hemoglobin level between 31 patients with anterior placenta and 9 with posterior placenta in placental incision group was not considered statistically significant. The frequency of cesarean hysterectomy was 6 patients in the anterior placenta and 1 in the posterior placenta in placental incision group, and not considered statistically significant.
Comparing the neonatal Apgar score between the two groups, there was no difference in signs that suggested mild fetal distress. Umbilical cord blood gas analysis results showed no difference between the two groups in the occurrence of blood acidosis below pH 7.20. The total duration of hospital stay for the newborns was a median of 6 days (range, 4 to 70 days) in the placental incision group and a median of 5 days (range, 4 to 24 days) in the non-incision group, showing an increased duration in the placental incision group (
There was no significant difference in neonatal prognosis described above between 31 patients with anterior placenta and 9 with posterior placenta in placental incision group.
For all the study subjects, we analyzed those cases in which capillary blood sampling was obtained in two-day old newborns to determine the presence of neonatal anemia due to blood loss during placental incision. Although not all newborns received blood tests, there was no statistical difference in the percentage of newborns tested between the two groups categorized according to the previous placental incision used.
In the newborn group that underwent blood testing, hemoglobin level and presence of anemia 2 days after delivery was compared between the placental incision group and non-incision group, and no statistically significant difference was observed between the two groups (
Placenta previa is the primary cause of neonatal anemia, and delivery of placenta previa pregnancy occurs generally through cesarean section. Although there are differences in uterine incision methods utilized, lower segment transverse incision has been reported in 71% to 96% of cases [
Before ultrasound was commonly utilized, placenta previa was diagnosed using radioactive isotopes such as 99mTc and ll3mln, but this is currently no longer practiced due to the risk of radiation exposure for mothers and fetuses and the difficulty of scanning [
As a surgical technique that avoids the placental incision, classical cesarean incision, inverted T cesarean incision, and medial-transverse incision have been used. In 2003, Ward [
According to research studies that reported the shortcomings of surgical techniques other than lower segment transverse uterine incision, Patterson et al. [
Based on data from mothers with placenta previa who delivered newborns through placental incision, Kim et al. [
We compared the changes in the preoperative hemoglobin level and the hemoglobin level 2 days after surgery from mothers who did not receive blood transfusion. For cases receiving blood transfusion, it was difficult to perform a correct statistical comparison using hemoglobin above a certain level. There was no difference between the two groups in the amount or frequency of blood transfusion received. Therefore, by comparing the hemoglobin change in mothers who did not receive blood transfusion, we presumed that we would be able to confirm that placental incision caused these differences in the amount of bleeding. The results revealed no differences between the two groups, and thus, placental incision does not affect the amount of bleeding after placenta expulsion. Moreover, 9 out of the 80 patients underwent cesarean hysterectomy, and approximately 11.6% to 16.7% of the study subjects in other related studies also underwent cesarean hysterectomy [
In conclusion, fetal delivery using lower segment transverse incision to incise the placenta for anterior placenta previa pregnancy is a safe surgical technique for mothers and newborns. This surgical technique is cost-effective because it reduces the number of imaging studies needed to find out incising site for avoiding the placental incision. Furthermore, using lower segment transverse uterine incisions, the uterine suturing is simple, duration of hospital stay is shorter, bleeding is reduced, and the risk of damaging the uterus after surgery is low. However, to successfully perform a surgical technique for fetal delivery through placental incision, the time of myometrial incision to fetal delivery must be minimized, and prompt decision-making and expertise of the obstetrician are needed.
Values are presented as mean±standard deviation, number (%), or number (range).
RBC, red blood cell.
Values are presented as mean±standard deviation, number (range), or number (%).
Values are presented as mean±standard deviation or number (%).