Chlamydia trachomatis infection in infants delivered by cesarean section

This report describes a well documented case of Chlamydia trachomatis pneumonia in a child delivered by cesarean section. The case indicates that infants delivered by cesarean section are still at risk of developing chlamydial infection. Various routes of infection are discussed, with a review of chlamydial disease in infants born by cesarean section.     

Adenosine concentration in umbilical cord blood of newborn infants after vaginal delivery and cesarean section

Umbilical blood was collected immediately at birth (less than 30 s) in full-term infants after vaginal deliveries (n = 33) and elective cesarean sections (n = 11). Blood gases, plasma adenosine, hypoxanthine, and catecholamine concentrations were determined. In vaginally born infants the median arterial adenosine concentration was found to be 0.46 microM (range 0.13-2.06) and the venous 0.48 microM (0.09-1.62). These levels were significantly higher (p less than 0.01) than in infants delivered by elective cesarean section; 0.16 microM (0.04-0.42) in the artery and 0.17 microM (0.02-0.56) in the vein. Vaginally born infants showed about a 4-fold higher level of umbilical arterial catecholamines than infants born by elective cesarean section. There was a strong inverse correlation between arterial hypoxanthine concentration and pH (r = -0.81, p less than 0.01). It is suggested that increased adenosine release at vaginal delivery modulates the stress response elicited by the strong catecholamine surge and may furthermore exert protective effects in perinatal asphyxia.     

Occurrence of Bifidobacterium in the feces of newborns delivered by cesarean section

In cesarean section newborns, colonization by Bifidobacterium occurs generally within 4 days of life. Breast-fed infants, independent of the delivery procedure, harbor a gastrointestinal flora characterized by a predominance of Bifidobacterium. Breast-fed [corrected] newborns delivered by cesarean section present a predominance of Bifidobacterium bifidum and bifidobacterium infantis in their stools. Investigation of variation in the incidence of Bifidobacterium among cesarean section newborns shows a larger variety of bifidobacterial species in an urban hospital. The prevalence of Bifidobacterium is lower in a newly constructed suburban hospital. Alimentation and environment hence seem to constitute important factors in the control of bifidobacterial flora.     

Neurological adaptation of infants delivered by emergency or elective cesarean section

The effects of intrapartal asphyxia on neonatal neurological condition have been studied in 17 full-term infants delivered by emergency cesarean section and in 30 full-term infants delivered by elective cesarean section used as controls. A neurological examination consisting of 31 items was performed on days 1, 2 and 5 after birth. A tonus score, an excitability score as well as the number of optimal responses were calculated. A follow-up examination was done at six months of age with a standardized neurological and developmental examination. The results showed that infants born after emergency cesarean section were significantly more hypotone the first two days after delivery than the infants in the elective cesarean section group. In regard to individual neurological items, significant differences were found between the emergency and elective cesarean section in reaction to sound, rooting, patellar, Moro and stepping reflexes with weaker reactions in the elective cesarean section group. Growth, psychomotor development and neurological status at six months did not differ significantly between the groups. Our findings indicate that full-term infants born after emergency cesarean section due to mild intrapartal asphyxia have a delayed neurological adaptation as expressed by poor muscular tonus during their first days of life compared with infants born after elective cesarean section.     

Levels of total and free tryptophan in maternal and in umbilical blood of infants born by vaginal delivery and by elective cesarean section

The variations of total and free tryptophan levels in samples of maternal and umbilical blood obtained on the occasion of elective cesarean section have been compared with similar samples taken from vaginal deliveries. In the neonates studied the umbilical blood levels of total and free tryptophan have been found to be higher than in the blood of the respective mothers, while the percentage of free tryptophan is comparable. In addition, the umbilical blood levels of both fractions of tryptophan appeared to be higher in newborn infants after spontaneous delivery than in those after elective cesarean section. These data show an active transport of tryptophan through the placental barrier that seems to be favored by spontaneous delivery.     

Establishment of functional residual capacity in infants delivered vaginally and by elective cesarean section.

Functional residual capacity (FRC) was measured with an open circuit N2 washout method in 20 vaginally born infants and 15 delivered by cesarean section, 30 and 120 min after birth. Umbilical artery blood was collected and analyzed for pH and catecholamine concentration. FRC was significantly higher in the cesarean section infants than in the vaginally delivered infants at 120 min of age (23.8 versus 16.8 ml/kg). The cesarean section infants also tended to have lower tidal volumes and higher respiratory frequencies than infants delivered vaginally. No significant correlation was found between catecholamine levels in umbilical artery and FRC in either group although there was a significant correlation between catecholamine level at birth and the increase of FRC from 30 to 120 min in the cesarean section group. It is suggested that the higher FRC, higher respiratory frequency and lower tidal volume in the cesarean section infants is an adaptation to a higher pulmonary water content to ensure an efficient gas exchange with the least respiratory work.     

Fetal and maternal plasma levels of gastrin, somatostatin and oxytocin after vaginal delivery and elective cesarean section

We measured the cord levels of gastrin, somatostatin and oxytocin with radioimmunoassay in plasma collected from the umbilical artery after vaginal delivery and after elective cesarean section. Maternal venous samples after the two labour modalities were also assayed for the same hormones. Fetal gastrin, somatostatin and oxytocin levels were significantly higher after vaginal delivery than after elective cesarean section. Independently of labour type, the fetal gastrin and somatostatin levels were always higher than the maternal levels. We suggest that the observed high levels of gastrin, somatostatin and oxytocin could be due to a stress-related stimulation of the oxytocin- as well as of the gastric gastrin- and somatostatin-producing cells, occurring particularly during vaginal delivery. The significant inverse correlation found between fetal pH and the recorded hormone levels is consistent with this hypothesis.     

Delayed neurological adaptation in infants delivered by elective cesarean section and the relation to catecholamine levels

We have studied the effect of mode of delivery and catecholamine (CA) surge at birth on neurobehaviour 1, 2 and 5 days after birth. Fifteen full-term infants were delivered by elective cesarean section (CS) and 15 full-term control infants were born vaginally. Infants born after elective CS were less excitable and had significantly reduced number of optimal responses during the first 2 days after delivery, compared to the controls. On the 5th day no significant neurological differences were found between the groups. Adrenaline and noradrenaline (NA) in umbilical arterial plasma were analysed in all infants. The mean values of NA were lower in the CS infants as compared to the vaginally delivered infants. Statistically significant correlations were found between low CA levels and poor muscle tone and/or lower grade of excitability in the CS infants. These results suggest that the high CA surge at birth might be of importance for the neurological adaptation after birth.     

喂养方式对剖宫产婴儿大便性状及肠道菌群的影响

目的 研究纯母乳喂养或纯配方奶喂养组对婴儿大便性状及肠道菌群的影响.方法 以健康足月剖宫产婴儿为观察对象,母乳喂养组和配方奶喂养组婴儿各30例.在婴儿6周龄时采集婴儿粪便标本,同时记录婴儿体质量、头围及大便情况.应用实时荧光定量PCR技术对肠道乳酸杆菌属、双歧杆菌属,以及双歧杆菌的某些重要亚种如长双歧等,进行定量检测.结果 母乳喂养婴儿的大便次数及大便含水量明显高于配方奶喂养婴儿.母乳喂养婴儿的双歧杆菌数量明显高于配方奶喂养婴儿(P ＜ 0.05);长双歧数量母乳喂养婴儿高于配方奶喂养婴儿,但两组间差异无统计学意义.结论 剖宫产母乳喂养儿的肠道双歧杆菌数量明显高于配方奶喂养儿.     

Serum bilirubin levels at 72 hours by selected characteristics in breastfed and formula-fed term infants delivered by cesarean section

The present multicenter study analysed the relative impact of maternal and infant factors on serum bilirubin levels at 72 +/- 12 h in exclusively breastfed vs formula-fed term infants. End-tidal carbon monoxide levels corrected for ambient air (ETCOc), an index of bilirubin production, were measured in exclusively breastfed (B = 66) or formula-fed (F = 210) term infants at 2-8 h of age. Inclusion criteria included cesarean section to ensure a 3 d hospitalization, birthweight > or = 2,500 g, gestational age >37 wk and absence of any illness. The ETCOc for B infants and F infants did not differ significantly (1.3 +/- 0.7 ppm vs 1.3 +/- 0.8 ppm). The serum bilirubin level at 72 +/- 12 h was significantly higher in B infants than in F infants (8.5 +/- 3.4mg dl(-1) vs 6.7 +/- 3.4mg dl(-1) p < 0.001), as was the percentage weight loss from birthweight. Serum bilirubin levels were significantly higher in infants who were male, who did not have meconium-stained amniotic fluid, and in those whose mothers were insulin-dependent diabetics or hypertensive. There was no difference between groups in the need for phototherapy or exchange transfusion. CONCLUSION: Although higher bilirubin levels were observed in group B at 72 +/- 12 h compared with group F, this finding was not of clinical or therapeutic consequence in this study. The lack of difference in ETCOc between the groups may be a factor of the timing of ETCOc measurement in this study, or may suggest that early increased bilirubin production is not a significant contributor to jaundice observed in exclusively breastfed infants. Key words: bilirubin, breastfeeding, jaundice