BackgroundThe benefits of breastfeeding for improved health and developmental outcomes in mothers and their infants have been widely recognized. The purpose of the present study was to assess whether feeding modes influence maternal blood pressure at one month postpartum.MethodsThe pregnancy charts of 407 women who delivered at a birthing center in rural Japan between August 1998 and September 2007 were analyzed. The criteria for inclusion were low-risk, full-term pregnancy (duration, 37–42 weeks) resulting in spontaneous vaginal deliveries, intrapartum hemorrhage < 500 mL, and a healthy infant (Apgar score ≥ 8 at one minute).ResultsThe subjects were classified into three groups based on feeding modes. The proportion of each mode was 28.3% in the breastfeeding group, 56.5% in the mixed-feeding group, and 15.2% in the formula-feeding group. The systolic blood pressure (SBP) in mothers at one month postpartum for each feeding mode was 118.4 ± 8.7 mmHg in the breastfeeding group, 120.6 ± 9.3 mmHg in the mixed-feeding group, and 122.0 ± 9.9 mmHg in the formula-feeding group. SBP at one month postpartum in the breastfeeding group was significantly lower than that in the other groups. No significant differences were observed in diastolic blood pressure in the three groups at one month postpartum.ConclusionBreastfeeding resulted in lower SBP in mothers at one month postpartum compared with those using other feeding modes, thus indicating an effect of breastfeeding on maternal blood pressure.

Oxidative stress is associated with the development of various diseases including cancer, arteriosclerosis, diabetes mellitus, hypertension and metabolic syndrome. However, little is known about the involvement of 8-hydroxydeoxyguanosine (8-OHdG) during the perinatal period. At present, few studies have investigated the precise correlations between 8-OHdG levels in cord blood (CB) and the physical conditions of the mother and neonate. To clarify the involvement of 8-OHdG during the perinatal period, the relationships between CB 8-OHdG levels and maternal/neonatal characteristics in vaginal deliveries were determined. The 8-OHdG levels of CB units collected from singleton gestation vaginal deliveries were analyzed. The relationships between 8-OHdG levels and perinatal characteristics were analyzed. The 8-OHdG levels in CB ranged from 0.1 to 1.39 ng/ml (median, 0.37 ng/ml). The relationships between 8-OHdG levels and the perinatal data were analyzed. The 8-OHdG levels detected in the non-smoking group were significantly lower compared to those in the smoking group. However, no significant correlation was observed between 8-OHdG levels and other maternal/ neonatal factors, including umbilical artery acid/base and gas values. Maternal smoking increases the level of the oxidative DNA damage biomarker 8-OHdG in CB. Since oxidative stress may influence the long-term health outcomes of infants after birth, understanding maternal and fetus/neonate stress conditions at delivery may help improve the health of fetuses and infants.

Previous studies have revealed correlations among prepregnancy body mass index (BMI), gestational weight gain and the birth weight of the infant. However, as a variety of indices relating to the physique have been used to assess the optimal weight of pregnant women, no conclusions have yet been established regarding the Japanese population. Therefore, the aim of this study was to analyze the correlations among prepregnancy BMI, gestational weight gain and the birth weight of the infant in primiparous and multiparous females. The study was a retrospective analysis of pregnancy charts from a single birthing center from August 1998 to the end of September 2007. The subjects were primiparous (n=220) and multiparous (n=340) females, and the mean prepregnancy weights of the two groups were 52.8±8.8 and 54.3±9.0 kg, respectively. The mean prepregnancy BMI of the primiparous females was 20.8±3.1 kg/m2, compared with 21.6±3.5 kg/m2 for the multiparous females, and the mean birth weights of the infants were 3,153.0±364.1 g and 3,262.3±370.4 g for primiparous and multiparous females, respectively. When the correlation between the maternal factors and the birth weight of the infant was analyzed, the birth weight was revealed to be positively correlated with delivery weight and gestational weight gain in primiparous females. However, no correlations were observed between the birth weight of the infant and prepregnancy weight or BMI. In multiparous females, birth weight was revealed to be positively correlated with prepregnancy weight, BMI and the maternal delivery weight; however, no correlation was observed between the birth weight of the infant and gestational weight gain. The results of the present study also demonstrated that there were significant differences between the primiparous and multiparous females, with regard to gestational weight gain and weight reduction following delivery. The study indicated that the factors influencing birth weight may be different for primiparous and multiparous females.

Breast-feeding and human milk are beneficial for both mothers and their children. This retrospective study aimed to clarify whether differences in feeding mode influence infant weight gain in the first month of life. We analyzed the pregnancy charts of 422 women who delivered at a birthing center in rural Japan between August 1998 and September 2007. The inclusion criteria were low-risk, full-term pregnancy (duration, 37–42 weeks), spontaneous vaginal delivery, and a healthy infant (1 min Apgar score of ≥8) who underwent a health check-up at 1 month postpartum. The subjects were classified into three groups on the basis of feeding modes: exclusive breast-feeding group (28.9%), mixed-feeding group (55.9%) and exclusive formula-feeding group (15.2%). The weight gain/day was 39.7±9.3 g (range, 18.5–67.4 g), 39.5±9.4 g (range, 13.8–64.5 g) and 39.0±9.5 g (range, 14.4–65.3 g) in the exclusive breast-feeding, mixed-feeding and exclusive formula-feeding groups, respectively. Apart from the rate of maternal smoking, which was lower in the exclusive breast-feeding group, no other significant differences were observed among the three groups. This study revealed that there were no differences in weight gain among infants raised exclusively on breast milk and those raised exclusively on formula milk.

Aim: To investigate the influence of umbilical cord blood (CB) acid-base status and gas values on the yield of mononuclear cells and CD34+ cells, pH, pCO2, pO2, HCO3 -and base excess were measured in arterial CB samples obtained from normal full-term deliveries. The relationship of these values with the yield of mononuclear cells and CD34+ cells detected in venous CB was analyzed. Material and Methods:A total of 145 CB units were collected from full-term vaginal deliveries at a single hospital. Immediately after delivery, a segment of the umbilical cord was double clamped, and arterial CB was analyzed to determine the acid-base status and gases. Venous CB was collected in a sterile collection bag and processed for cell separation within 24 h of collection. The relationship between umbilical arterial acid-base status, each gas value, and the yield of mononuclear cells and CD34 + cells was analyzed.Results: Statistically significant correlations were observed between the net weight of CB and the total mononuclear and CD34 + cell counts. In addition, there was a negative correlation between the mononuclear cell counts and pH, but a positive correlation between the mononuclear cell counts and pCO2. However, no significant differences were observed between the primipara and multipara groups in terms of the net weight of CB, total mononuclear cell counts and total CD34 + cell counts. Conclusion:The findings of the present study show that the mononuclear cell counts are correlated with arterial CB pH and pCO2, suggesting the involvement of fetal hypoxia on the yield of mononuclear cells.