ABSTRACT
Conclusion:
Withlimited data available for admission indications to the NICU of newborns born from term pregnancies, we found that the mode of delivery affects hospitalization indications of newborns, need for support, and Apgar scores. Early term delivery is associated with higher rates of neonatal morbidity and admission to the NICU. Better maternal care and prevention of factors that may lead to preterm birth will provide the prevention and management of these problems.
Results:
There was no significant difference between vaginal delivery and cesarean section groups in terms of the indications for admission to the NICU of term low-risk pregnant women (p=0.91, p=0.17). A higher admission in the NICU was found in the early term group. The early term group required more respiratory support compared to the full term group (p=0.02). When the groups were compared in terms of IV fluid treatment support, hypoglycemia or feeding difficulty, and jaundice requiring phototherapy, no significant difference was found.
Materials and Methods:
In this study, 300 pregnant women who gave birth in our tertiary hospital was included. The records of newborns admitted to the NICU of these pregnant women were reviewed between January 1, 2019 and January 1, 2021. Durations of newborn hospitalizations and problems encountered during admission were recorded. The results were statistically evaluated.
Objective:
The aim of this study was to evaluate the short-term results of perinatal health in vaginal and cesarean deliveries and the indications for admission to the neonatal intensive care unit (NICU) in terms of healthy singleton pregnancies.
PRECIS: We concluded that the mode of delivery affects hospitalization indications of newborns, need for support, and Apgar scores. Early term delivery is associated with higher rates of neonatal morbidity and admission to the NICU.
Introduction
The definition of term pregnancy is relative. Increasing evidence has shown that neonatal outcomes of early- and full-term infants are different. Early-term newborns have more respiratory distress requiring mechanical ventilation and longer hospital stays. Mortality is increased in these cases. Neonatal intensive care unit (NICU) admission probability compared to term infants is significantly higher(1,2).There appears to be a sustained relationship between neonatal morbidity and gestational age in specific term and preterm labors(3).
For the fetus, the effects of labor on the baby are not clear. Ongoing pregnancies may result in stillbirth or the need for NICU. Some studies indicate that patients who delivered vaginally need NICU at a higher rate than pregnant women who gave birth by cesarean section. In a study comparing cesarean and vaginal deliveries, the number of newborns with an Apgar score below 7 in the first minute was found to be higher in the cesarean section group. In the same study, the 7th minute Apgar score and umbilical cord pH were found to be similar between the two groups(4,5). Cesarean deliveries can be a life-saving procedure. Adverse events may occur in both mothers and newborns(6,7).
While asphyxia, trauma and meconium aspiration decrease in cesarean delivery, the risk of transient tachypnea of the newborn, surfactant deficiency and respiratory distress secondary to pulmonary hypertension increases. Physiological events in the last weeks of pregnancy are accompanied by changes in the hormonal environment of the fetus and mother with the onset of spontaneous delivery. The fetus is prepared for neonatal transition(8).
The most common neonatal complications in admission to the NICU are respiratory morbidity, hypoglycemia, and sepsis. Newborn pulmonary problems, especially respiratory distress syndrome (RDS), may follow cesarean delivery. Moreover, the admission of the newborn to the NICU has various negative effects on the family(9).
In the literature, there are insufficient evidence evaluating the indications for admission to NICU in term healthy singleton pregnancies according to the mode of delivery. In this study, we evaluated the short-term results of perinatal health in vaginal and cesarean deliveries and the indications for admission to the NICU.
Materials and Methods
The study was planned retrospectively and approved by the ethics committee at the Ankara City Hospital (approval no: E1-20-295).
The hospital records of pregnant women hospitalized for delivery in Ankara City Hospital NICU between January 1, 2019 and January 2021 were analyzed from accumulated data. Women who gave consent for the study were between 37th and 42nd gestational weeks so they are term healthy singleton pregnant women without any additional systemic diseases. Vaginal delivery and cesarean section were included. Due to the need for intensive care, the babies were hospitalized and then discharged as healthy. The data of the patients were obtained retrospectively from computer records and patient files. Deliveries were categorized according to weeks of gestation. The date of the last menstrual period was taken as the basis for determining the gestational age. When pregnant women whose ultrasound measurements were inconsistent with the last menstrual period or in those who did not know or remember the last menstrual period, gestational age was determined according to the earliest ultrasound measurements.
Those who were born under 37 weeks, pre-pregnancy genital and extragenital disease, hypertension, preeclampsia, gestational diabetes, goiter, anxiety and depressive disease, drug addiction, multiple pregnancy, maternal age below 18 and over 45, fetuses with anomalies in detailed ultrasonography, patients with premature rupture of membranes, additional systemic disease, obstetric conditions that may cause premature or emergency delivery, pre-eclampsia and those whose medical records could not be reached were excluded from the study. Indications for NICU admission and maternal demographic and labor characteristics were retrospectively evaluated from the file records. Demographic data collected included; age, gravidity, parity, gestational age at cesarean section, birth weight, hypoglycemia, length of hospitalization, respiratory morbidity, need for NICU admission, mechanical ventilation and phototherapy.
Statistical Analysis
All data related to the disease were recorded in SPSS 22.0 (SPSS for Windows Evaluation, Illinois, Chicago, USA) and statistical analyses were performed. Arithmetic mean ± standard deviation for descriptive parametric data from the vaginal labor group and the cesarean section group, and ratios and percentages were used for nonparametric data. The distribution of the data was evaluated by the Kolmogorov-Smirnov test. The independent t test or Mann-Whitney U test was used to compare parametric values between the two groups. Nonparametric values were compared between the two groups by Pearson’s chi-square test or Fisher’s exact test. P<0.05 was considered statistically significant.
Results
A three hundred pregnant women were included in this study group. One hundred eighty two had vaginal deliveries and 118 had cesarean deliveries. The main demographic characteristics of the patients are shown in Table 1.
There was no significant difference between the distribution of the mean age of women according to the mode of delivery. The mean gestational age of women was 37.6±1.9 weeks and 37.3±1.8 weeks for the vaginal delivery group and the cesarean group respectively (p>0.05, p=0.37). There was no statistically significant difference between the groups in terms of duration of hospital stay, estimated fetal weight, newborn birth weight and birth length (p>0.05, p=0.23, p=0.12, p=0.84, and p=0.74 respectively). The rates of pregnant women with premature rupture of membranes were 18.6% and 11.8% for the vaginal delivery group and the cesarean group, respectively (Table 2). The indications for admission to the NICU were compared according to the mode of delivery. Transient tachypnea of the newborn was 6.4% in the vaginal delivery group and 21.1% in the cesarean section group. Meconium-stained amniotic fluid was 11.5% and 9.3% for the vaginal delivery group and cesarean group respectively. Congenital pneumonia was 3.2% and 3.3% respectively. Early sepsis was 3.8% and 2.5% respectvely. There was no significant difference between vaginal delivery and cesarean section groups in terms of indications for admission to the NICU (p>0.05). The results are summarized in Table 3.
Hundred and forty early - term and 160 full - term pregnant women were hospitalized. A higher admission to the NICU was found in the early-term group. The early term group had a higher need for respiratory support compared to the full term group (p<0.05, p=0.02). When the groups were compared for need iv fluid treatment, hypoglycemia, feeding difficulty, and jaundice requiring phototherapy, there was no significant difference (p>0.05, p=0.36, p=0.32, and p=0.21 respectively) Table 4.
Discussion
Neonatal morbidity rates vary with the mode of delivery. The infants born by cesarean section are more likely to develop respiratory morbidity. In contrast, infants born vaginally are more likely to develop intracranial hemorrhage, brachial plexus injury, and culture-positive neonatal sepsis(10,11).
Life-threatening maternal outcomes are more common in cesarean deliveries regardless of previous vaginal delivery history. In the literature, the age ranges of pregnant women vary in studies investigating the indications for admission in the NICU according to the mode of delivery(12,13).
Catalano and Sacks(13) found 31.2±5.7 years for pregnant women. Similar to our study, in another study, the mean age was again 29.3±6.6 years. In our study, the mean age of pregnant women was 27.3±5 years. Similar studies have revealed that the age of women giving birth differs between 27 and 38.9 years(14).
Transient tachypnea of the newborn was first described by Avery et al.(15) in 1966. The main cause is the inability to excrete fluid. In our study, temporary tachypnea was found in 12 and 25 newborns in the term low-risk vaginally delivery group and newborns in the cesarean section group, respectively. The results were consistent with the literature(16).
In the study of Dani et al.(17), 11% of the newborns were admitted to the intensive care unit due to respiratory problems. RDS were diagnosed in 6% of them. In our study, the RDS rates were 2.7 and 11.8 for the vaginal delivery group and the cesarean group, respectively.
Mothers who had vaginal labor started breastfeeding earlier than those who had cesarean section. Especially women who have general anesthesia during C-sections start breastfeeding later than those who gave labor vaginally. It is thought that there may be a significant decrease in the comfort of mothers compared to those who gave vaginal labor due to reasons such as pain, fatigue, and negative effects of anesthesia after cesarean delivery(16). In our study, feeding difficulty was seen in 11.8% and 9.8% of early term newborns and full-term newborns, respectively.
In the literature, Apgar scores of newborns were examined according to delivery mode. 1st and 5th minute Apgar scores of newborns with vaginal delivery were found to be higher than cesarean section deliveries(18,19,20). In our study, there was no difference between the two groups according to Apgar scores (p>0.05).
In obstetric and pediatric practice, late preterm infants are often considered functionally and developmentally mature and are often managed by protocols developed for full-term infants. It is well known that cesarean delivery is an important factor that causes morbidity in newborns(13). Cesarean delivery has been reported to cause a longer hospital stay and more respiratory morbidities(11,12). In our study, the most common cause of admission to the NICU was respiratory morbidities. Transient tachypnea of the newborn is the most common among these morbidities. In line with the literature, the hospital stay was longer in the cesarean delivery group(21,22).
Hypoglycemia and electrolyte disorders are reported to be more common morbidities in early-term newborns. In our study, hypoglycemia was more common in early-term newborns. Our finding was consistent with the literature. However, when compared with term newborns, it was not statistically significant. In our study, more dehydration was observed in premature term newborns. IV hydration was applied to them(23).
The need for IV antibiotic therapy was higher in the early-term group in our study, as indicated in the literature(21). Antibiotic treatment was given with the indication of maternal urinary tract infection and positive cervical culture.
When the literature was reviewed, Binarbaşı et al.(24) found feeding problems with a rate of 9.1% in a study on late preterm infants. In addition, the admission rate due to nutritional intolerance was found to be 5.3%. In our study, it was found to be 11.8 in early term and 9.3 in late term pregnancies. As stated in the literature, this can be explained by the slower sucking of these babies and the more frequent feeding intolerance. Since a significant number of newborns were hospitalized due to respiratory distress, the delayed onset of feeding can also be considered as a factor(24).
McIntire and Lenevo(25) compared the neonatal outcome of late preterm infants with that of infants born at 39 weeks of gestation. Overall, the rate of neonatal morbidity in their report seems to be higher than in our study, especially about respiratory complications and clinical jaundice requiring phototherapy. In contrast to our study, cesarean delivery was not associated with an increased risk of neonatal morbidity. In the study of Bastek et al.(26) cesarean delivery was a significant risk factor for neonatal morbidity. The relationship of respiratory complications with parity was not reported in previous studies.
In recent years, the effect of mode of delivery (eg, vaginal delivery or cesarean section) on newborns born from term pregnancies has been examined due to the increasing rates of cesarean section and their association with allergic and autoimmune diseases(27,28).
In our study, in terms of meconium-stained amniotic fluid, there was no significant difference between cesarean section and vaginal delivery groups (p=0.87). Other small-sample studies also showed no significant difference in meconium between newborns delivered by C-section and vaginally(29).
Hu et al. evaluated meconium-stained amniotic fluid microbiota in full-term cesarean section and vaginal birth groups.
Their study reported no significant differences in the meconium microbiota of full-term vaginally and cesarean section-delivered newborns(30).
We could not evaluate the meconium microbiota in our study because we had no data.
Study Limitations
There are several limitations to our study, which are mainly related to its retrospective design and relatively small number of patients. The study was single-center. Late preterm babies may be more likely to be diagnosed with more subjective diagnoses (transient tachypnea of the newborn, sepsis diagnosis) than term babies. However, Another limitation is that we do not have data on long - term neonatal outcomes.
Conclusion
With the limited data available for admission indications on term pregnancies, the results of the study showed that the mode of delivery affects the indications for hospitalization, the need for help and support, and the Apgar scores of newborns. This finding should be considered while deciding on the mode of delivery. However, in cases where vaginal delivery is not possible or delayed delivery is dangerous for the mother or the baby, cesarean section should be performed.