Serum tryptophan and 5-hydroxytryptophan at birth and during post-partum days.

Serum levels of tryptophan (Trp) and 5-hydroxytryptophan (5-HTP) were measured in the mother at birth, by normal delivery or cesarean section, on days 1 and 3 post-partum, and in the cord blood of the fetus-newborns. Decreases in Trp and 5-HTP levels during delivery were noted. Conversely, Trp levels in the cord blood of fetus-newborns were significantly higher than those of their mothers, and 5-HTP levels also showed a tendency to increase , whereas on day 1 post-partum Trp values were lower than those in fetal cord, but higher than those during spontaneous delivery. On day 3 post-partum, serum Trp levels were higher than those during spontaneous delivery, but similar to those on day 1. 5-HTP values tended to decrease with respect to those of day 1. Serum Trp and 5-HTP concentrations decreased significantly on day 1 post-partum after cesarean section, but increased on day 3, demonstrating that maternal Trp was being consumed during delivery. A major release of prolactin in serum on days 1 and 3 post-partum there was in women with normal delivery, revealing a correlation between Trp and prolactin in the first few days after birth, in relation to different conditions of delivery.

Maternal serum levels of human chorionic somatotropin correlates with transferrin and erythropoietin in pregnancy.

During pregnancy, plasma levels of erythropoietin (EPO) and transferrin (TSF) show a gradual increase till term, when a slight decrease occurs. Human chorionic somatotropin (hCS) is a peptide hormone with a direct effect on the function of the syncytiotrophoblast and on the mass of functional placental tissue. In order to understand the relationships between the placental functions, maternal erythropoiesis and iron transfer to the fetus, the relationships between EPO and hCS and between TSF and hCS were investigated. A group of healthy pregnant women (n = 190) attending the Obstetric Clinic of the University of Siena were studied. They were between 18 and 43 weeks pregnant. A single blood sample was taken from each patient by radial vein puncture on admission into the clinic before the beginning of any therapy, for the determination of haemoglobin, EPO, ferritin, serum iron, TSF and hCS. The highest correlation was that between hCS and TSF (r = 0.336, p < 0.0001). This correlation was significant in anaemic patients and lost its significance in non-anaemic patients. In our study, we also found a significant relationship between hCS and logEPO (r = 0.195; p < 0.01) which reached an elevated significance over the entire survey, but did not reach statistical significance in anaemic women. We hypothesise that in pregnancy chorionic villi develop a great capacity to respond to pathological maternal events with the result of regulating the transport of iron, the oxygen tension and the maternal-fetal transfer of oxygen through haemoglobin. Evidently, the response of the villi serves to balance the lack of iron in favour of the fetus, probably through a mechanism that links the variations of the iron transport on the maternal side and the increased use on the fetal side through a dynamic and consensual response by the chorionic villi.