Effects of intake of K-containing food among passive-smoking pregnant women on prevention of neonatal bleeding

2002 Fiscal Year Final Research Report Summary

• Project/Area Number: 13672525
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Clinical nursing
• Research Institution: Mie Prefectural College of Nursing
• Principal Investigator: NAGAMI Keiko Mie Prefectural College of Nursing, Nursing Science Department, Assistant Professor, 看護学部, 講師 (10218026)
• Co-Investigator(Kenkyū-buntansha): MURASHIMA Seikou Mie Prefectural College of Nursing, 看護学部, 教授 (20166276)
• Project Period (FY): 2001 – 2002
• Keywords: vitamin K / cord blood / vitamin K-dependent clotting factor / passive smoking / neonate

Research Abstract

Study objective : The objectives of the present study were to elucidate the effects of passive smoking during pregnancy on changes in vitamin K-dependent clotting factor activity in cord blood, and to determine the effects of the intake of vitamin K-containing food among passive smoking pregnant women on prevention of neonatal bleeding, from the perspective of the transplacental supply of vitamin K.
Study methods : Subjects were 148 non-smoking women who underwent vaginal delivery (passive smoking group, n=53; non-passive smoking group, n=95). Consent was obtained following written and oral explanations. Following delivery, citric acid-added plasma obtained from collection of umbilical venous blood was used to investigate the following : prothrombin time, activated partial thromboplastin time, hepaplastin test, thrombotest, vitamin K-dependent clotting factor activity (FII, FVII, FIX, FX) and non-vitamin K-dependent clotting factor activity. In addition, a method for measuring vitamin K in cord blood was investigated based on Wakabayashi et al.(Folia Pharmacol.Jpn.116)'s HPLC using platinum catalyst reduction and electrochemical detection.
Results and discussion : The passive smoking group had significantly lower FVII and FIX than the non-passive smoking group. Comparison of the two groups with regard to the intake of fermented soybeans revealed a significantly higher FVII in the non-passive smoking group relative to the passive smoking group in the non-intake group, with no significant intergroup differences in the intake group. Comparison of the two groups with regard to the intake of broccoli revealed a significantly higher thrombotest value in the non-passive smoking group relative to the passive smoking group in the non-intake group, with no significant intergroup differences in the intake group. For pregnant women who may have difficulty avoiding passive smoking, regular intake of vitamin K-containing food may improve the activity of vitamin K-dependent clotting factors in fetal blood and thus provide a means of preventing early neonatal bleeding.