EFFECTS OF AN ANTENATAL LOAD OF PYRIDOXINE (VITAMIN B₆) ON THE BLOOD OXYGEN AFFINITY AND PROLACTIN LEVELS IN NEWBORN INFANTS AND THEIR MOTHERS

Abstract

The effects of a loading dose of pyridoxine (100 mg) given intramuscularly or per os to 24 earlier non-supplemented pregnant women at term was investigated. The in vitro oxygen affinity (P50) and the prolactin level in both maternal and newborn blood was sampled. The blood P50 values were measured by a variant of "mixing method". Blood prolactin levels were determined by RIA. After pyridoxine administration, the maternal P50 values increased moderately and the newborns' cord blood P50 values increased significantly when compared with the control group's (number of cases 12) values. The decrease of blood oxygen affinity was most pronounced in the supplemented groups in newborns' capillary blood at the age of five days. The pyridoxine supplementation had no effect on the maternal and the newborns' cord blood prolactin level or on the daily amount of breast milk. Pyridoxine supplementation of the mother at labour may influence favourably the oxygen transport function of the newborn's blood and it may be especially advantageous in early postnatal adaptation disturbances of newborns.

Diseases Associated with Defects in Vitamin B6 Metabolism or Utilization

“…Toxemia can further increase maternal require ments for pyridoxine (144). Temesvari et al (162) found that 100 mg of pyridoxine given to pregnant women at term decreased maternal and new borns' cord blood oxygen affinity (i.e. increased P50).…”

Suboptimal maternal and cord plasma pyridoxal 5′ phosphate concentrations are uncommon in a cohort of Canadian pregnant women and newborn infants

“…However, it is still unknown whether it is optimal to maintain plasma PLP concentrations >20 nmol/L during pregnancy (Simpson et al, 2010). Few clinical studies have suggested that high vitamin B 6 status during pregnancy is associated with decreased prenatal nausea and vomiting (Babaei & Foghaha, 2014;Sahakian, Rouse, Sipes, Rose, & Niebyl, 1991;Vutyavanich, Wongtra-ngan, & Ruangsri, 1995), higher Apgar scores (Schuster et al, 1984;Temesvari et al, 1983), higher birth weights (Chang, 1999), reduced incidence of preeclampsia (de la Calle et al, 2003) and preterm birth (Ronnenberg et al, 2002), and a protection against orofacial clefts (Krapels et al, 2004) and cardiovascular malformations (Czeizel, Puho, Banhidy, & Acs, 2004;Salam et al, 2015). However, these purported associations have not unequivocally been demonstrated (Chen et al, 2015;Heller et al, 1973;Salam et al, 2015).…”

“…During pregnancy, low vitamin B 6 status has been linked to adverse pregnancy and birth outcomes (Ronnenberg et al, ; Ronnenberg et al, ; Schuster, Bailey, & Mahan, ), but not all studies have shown an association (Chen et al, ; Heller, Salkeld, & Körner, ). A recent systematic review of four randomized controlled trials (Hillman, Cabaud, Nilsson, Arpin, & Tufano, ; Schuster, Bailey, & Mahan, ; Swartwout, Unglaub, & Smith, ; Temesvari, Szilagyi, Eck, & Boda, ) has found no convincing evidence to support maternal or neonatal clinical benefits of vitamin B 6 supplementation during pregnancy (Salam et al, ).…”

Interventions with Vitamins B6, B12 and C in Pregnancy

“…Doses of 50–510 mg/day taken during the first trimester have not been associated with adverse fetal outcomes 24,26,27 . In addition, pyridoxine supplementation has been used therapeutically to suppress prolactin secretion and inhibit lactation, 28 though its efficacy has not been demonstrated consistently 29–32 …”