Vitamin K and childhood cancer: a population based case-control study in Lower Saxony, Germany

Early Life Nutrition Factors and Risk of Acute Leukemia in Children: Systematic Review and Meta-Analysis

Acute leukemia commonly occurs in young children with peak incidence at the age of 2-5 years. However, the etiology is still unclear and many preventable risk factors still deserve to be reviewed. The focus of this systematic review and meta-analysis is to summarize the evidence concerning early life nourishment (breastfeeding, early life diet), neonatal vitamin K administration and the risk of acute leukemia. All epidemiological studies published up to June 2023 and assessing diet-related risk factors for childhood acute leukemia were identified in two electronic databases (PubMed and Web of Science), with no limits on publication year or language. A total of 38 studies (37 case-control studies and 1 study with pooled analysis) were included. The published risk estimates were combined into a meta-analysis using the Generic Inverse Variance method. The current evidence shows that breastfeeding (yes vs. no) has a protective effect against acute lymphoblastic leukemia (odds ratio = 0.85; 95% CI, 0.76-0.94). Evidence related to the role of other studied factors (foods and supplements) is inconclusive. Further research into the potential role of diet in early life and the risk of acute leukemia is needed to develop prevention strategies at population level. Review Registration: PROSPERO registration no. CRD42019128937.

A Practical Guide to the Management of the Fetus and Newborn With Hemophilia

Newborns with hemophilia are at risk of intracranial hemorrhage, extracranial hemorrhage, and other bleeding complications. The safe delivery of a healthy newborn with hemophilia is a complex process that can begin even before conception, and continues throughout pregnancy, birth, and the newborn period. This process involves the expectant parents and a wide variety of health-care professionals: genetic counselors, obstetricians, neonatologists, pediatricians, radiologists, adult and pediatric hematologists, and nurses with expertise in hemophilia. Because of this multidisciplinary complexity, the relative rarity of births of newborns with hemophilia, and the lack of high-quality evidence to inform decisions, there is considerable variation in practice in this area. We present a comprehensive multidisciplinary approach, from preconception counseling to discharge planning after birth, and describe available options for management decisions. We highlight a number of areas of important uncertainty and controversy, including the preferred mode of delivery, the appropriate use and timing of neuroimaging tests, and the appropriate use of clotting factor concentrates in the newborn period. While the approach presented here will aid clinicians in planning and providing care, further research is required to optimize the care of newborns with hemophilia.

Birthweight by gestational age and childhood cancer

The objective of this research was to compare the association of birthweight alone with gender-specific birthweight-for-gestational age on childhood cancer risk in a large population-based case-control study in Germany. Incident cases of childhood cancer (n=2,024, diagnosed 1992-1994) were ascertained from the German Childhood Cancer Registry. Controls were randomly drawn from population registries. Parents reported risk factor information in a mailed questionnaire and telephone interview. The odds ratio for acute lymphoblastic leukemia (ALL) was 1.41 (95% confidence interval 1.08-1.84) in the high-birthweight category (>4 kg) and was 1.45 (1.07-1.97) in the large-for-gestational age (LGA) category compared to the normal birthweight (2.5-4 kg) and the appropriate-for-gestational age (AGA) categories, respectively. However, the agreement between the birthweight and birthweight-for-gestational age was only moderate. Subgroup analyses revealed elevated odds ratios for ALL and CNS tumors in first born's who were LGA but of normal birth weight. Thus, two findings from this post-hoc analysis are worthy of note: (1) the use of birthweight-for-gestation age categories within birthweight sub-groups potentially identified new high-risk groups among firstborns for ALL tumors and among all children for CNS tumors; and (2) although the magnitudes of risk estimators for ALL were comparable in the traditional high-birthweight group and in the LGA, the same children were not jointly classified in the same newborn categories indicating two potentially different subsets of children at risk.

Vitamins for babies and young children

The Welfare Food Scheme has recently been reviewed, and, although changes are being made, free vitamin supplements for children <4 years old will remain an important part of the new "Healthy Start" scheme. Establishing precise daily requirements for vitamins is not easy, and there is considerable individual variation; however, achieving the reference nutrient intake (RNI) should be possible with a healthy balanced diet for all except vitamins K and D, which require additional physiological or metabolic processes. For vitamin K, there is a well-established neonatal supplementation programme, and clinical deficiency is extremely rare. For vitamin D, however, supplementation is inconsistent, and both clinical and subclinical deficiencies are not uncommon in young children in the UK, particularly infants of Asian and Afro-Caribbean ethnic origin, and those who have prolonged exclusive breast feeding and delayed weaning. Most vitamin supplements contain vitamins A, C and D, with or without some of the B group of vitamins. There is clinical and dietary evidence to support vitamin D supplementation and some evidence from dietary surveys that vitamin A intakes may be low; however, there is no evidence to support supplementation of diets of UK children with water-soluble vitamins. Future strategy should aim at education of the public and health professionals regarding dietary intake and physiological aspects of vitamin sufficiency, as well as increasing awareness and availability of supplements, particularly of vitamin D, for those at increased risk of deficiency.

Socioeconomic status and childhood leukaemia: a review

BACKGROUND

A long-held view links higher socioeconomic status (SES) to higher rates of childhood leukaemia. Some recent studies exhibit associations in the opposite direction.

METHODS

We reviewed journal literature through August 2002 for associations between childhood leukaemia and socioeconomic measures. We determined the direction of each association and its P-value. We described the results with regard to study design, calendar period, geographic locale, and level of the socioeconomic measures (individual or ecological). For measures with sufficient number of results, we computed summary P-values across studies.

RESULTS

Case-control studies conducted in North America since 1980 have involved subject interviews or self-administered questionnaires and have consistently reported inverse (negative) associations of childhood leukaemia with individual-level measures of family income, mother's education, and father's education. In contrast, associations have been consistently positive with father's occupational class in record-based case-control studies and with average occupational class in ecological studies.

CONCLUSIONS

Connections of SES measures to childhood leukaemia are likely to vary with place and time. Validation studies are needed to estimate SES-related selection and participation in case-control studies. Because different socioeconomic measures (such as income and education) and individual-level and ecological-level measures may represent different risk factors, we advise researchers to report these measures separately rather than in summary indices of social class.

Vitamin K and childhood cancer: a report from the United Kingdom Childhood Cancer Study

The relationship between neonatal vitamin K received by the intramuscular (i.m.) route and the development of leukaemia or other cancers was investigated as part of a national case–control study of childhood cancer, using data abstracted from obstetric and neonatal records. The analyses included 2530 children diagnosed with cancer before 15 years of age, 1174 of whom had leukaemia and 4487 control children without cancer. Overall, 39% of cases and 42% of controls had records of i.m. vitamin K administration, while 24% of cases and 22% of controls had no record of whether or not they had received vitamin K. Using subjects who received i.m. vitamin K as the baseline group, our analyses found no association between the administration of i.m. vitamin K and either leukaemia or other cancers as a group. We conclude that there is no convincing evidence that neonatal vitamin K administration, irrespective of the route by which it is given, influences the risk of children developing leukaemia or any other cancer.

Vitamin K and childhood cancer: analysis of individual patient data from six case-control studies

To investigate the hypothesis that neonates who receive intramuscular vitamin K are at an increased risk of developing cancer, particularly leukaemia, a pooled analysis of individual patient data from six case-control studies conducted in Great Britain and Germany has been undertaken. Subjects comprised 2431 case children diagnosed with cancer before 15 years of age and 6338 control children. The retrospective assessment of whether or not an individual baby received vitamin K is not straightforward. In many cases no record was found in stored medical notes and two types of analysis were therefore conducted; in the first it was assumed that where no written record of vitamin K was found it had not been given, and in the second, where no written record of administration was found, information on hospital policy and perinatal morbidity was used to 'impute' whether or not vitamin K had been given. In the first analysis, no association was found between neonatal administration of intramuscular. vitamin K and childhood cancer: odds ratios adjusted for mode of delivery, admission to special care baby unit and low birth weight were 1.09 (95% confidence interval 0.92-1.28) for leukaemia and 1.05 (0.92-1.20) for other cancers. In the second analysis, the adjusted odds ratios increased to 1.21 (1.02-1.44) for leukaemia and 1.10 (0.95-1.26) for other cancers. This shift did not occur in all studies, and when data from the hypothesis generating Bristol study were excluded, the adjusted odds ratios for leukaemia became 1.06 (0.89-1.25) in the first analysis and 1.16 (0.97-1.39) when data on prophylaxis imputed from hospital policy and perinatal morbidity were used. We conclude that whilst the broad nature of the diagnostic groups and the poor quality of some of the vitamin K data mean that small effects cannot be entirely ruled out, our analysis provides no convincing evidence that intramuscular vitamin K is associated with childhood leukaemia.

Vitamin K status of premature infants: implications for current recommendations

OBJECTIVE

Newborn infants are vitamin K deficient. Vitamin K status in full-term infants after intramuscular vitamin K supplementation at birth has been described. Similar information in growing premature infants has not been reported. The objective of this study was to assess vitamin K status in premature infants by measuring plasma vitamin K and plasma protein-induced in vitamin K absence (PIVKA II) from birth until 40 weeks' postconceptional age.

METHODS

Premature infants (</=36 weeks' gestation) were divided at birth into groups by gestational age (group 1, </=28 weeks; group 2, 29-32 weeks; group 3, 33-36 weeks). Supplemental vitamin K (1 mg intramuscularly) was administered at birth followed by 60 microg/day (weight <1000 g) or 130 microg/day (weight >/=1000 g) via total parenteral nutrition. After hyperalimentation, most received vitamin K-fortified enteral feedings with the remainder receiving unfortified breast milk. Blood was obtained for PIVKA II in cord blood and for PIVKA II and vitamin K at 2 weeks and 6 weeks after birth and at 40 weeks' postconception.

RESULTS

Of the 44 infants enrolled, 10 infants in each gestational age group completed the study. The patient characteristics for groups 1, 2, and 3 were as follows: gestational age, 26.3 +/- 1.7, 30.3 +/- 1.3, and 33.9 +/- 1.1 weeks; birth weight, 876 +/- 176, 1365 +/- 186, and 1906 +/- 163 g; and days of hyperalimentation, 28.9 +/- 16, 16.8 +/- 12, and 4.3 +/- 4 days, respectively. At 2 weeks of age, the vitamin K intake and plasma levels were highest in group 1 versus group 3 (intake: 71.2 +/- 39.6 vs 13.4 +/- 16.3 microg/kg/day; plasma levels: 130.7 +/- 125.6 vs 27.2 +/- 24.4 ng/mL). By 40 weeks' postconception, the vitamin K intake and plasma levels were similar in all 3 groups (group 1, 2, and 3: intake, 11.4 +/- 2.5, 15.4 +/- 6.0, and 10.0 +/- 7.0 microg/kg/day; plasma level, 5.4 +/- 3.8, 5.9 +/- 3.9, and 9.3 +/- 8.5 ng/mL). None of the postnatal plasma samples had any detectable PIVKA II.

CONCLUSIONS

Premature infants at 2 weeks of age have high plasma vitamin K levels compared with those at 40 weeks' postconceptional age secondary to the parenteral administration of large amounts of vitamin K. By 40 weeks' postconception, these values are similar to those in term formula-fed infants. Confirming "adequate vitamin K status," PIVKA II was undetectable by 2 weeks of life in all of the premature infants. With the potential for unforeseen consequences of high vitamin K levels, consideration should be given to reducing the amount of parenteral vitamin K supplementation in the first few weeks of life in premature infants.vitamin K, PIVKA II, premature, total parenteral nutrition, enteral nutrition.

Vitamin K policies and midwifery practice: questionnaire survey

OBJECTIVES

To investigate policies on neonatal vitamin K and their implementation.

DESIGN

Two phase postal survey.

SETTING

United Kingdom.

PARTICIPANTS

A 10% random sample of midwives registered with the United Kingdom Central Council for nursing, midwifery, and health visiting. Of 3191 midwives in the sample, 2515 (79%) responded to phase one and 2294 (72%) completed questionnaires on their current jobs (November 1998 to May 1999). In phase two, 853 (62%) of 1383 eligible midwives gave details on 2179 of their earliest jobs (start dates before 1990).

RESULTS

All the midwives in clinical practice at the time of the survey (2271, 99%) reported that they were working in areas with official policies on neonatal vitamin K. Seven distinct policies were described: intramuscular vitamin K for all babies (1159, 51.0%); intramuscular vitamin K for babies at "high risk," oral for others (470, 20.7%); oral vitamin K for all babies (323, 14.2%); parental choice for all (124, 5.5%); parental choice for all except babies at high risk, (119, 5.2%); intramuscular vitamin K for babies at high risk only (33, 1.5%); oral vitamin K for babies at high risk only (17, 0.7%); and a disparate group of policies including intravenous vitamin K for some babies (26, 1.1%). Previous policies were (and some may still be) open to individual interpretation and were not always followed.

CONCLUSIONS

Hospital policy is not necessarily a good guide to individual practice. The primary purpose of clinical records is to document patient care, and recording practices reflect this. There is considerable variation in vitamin K policies and midwifery practice in the United Kingdom, and there is no clear consensus on which babies should receive vitamin K intramuscularly.

Vitamin K in neonates: how to administer, when and to whom

Vitamin K-dependent factors are lower in neonates than in adults, and these anomalies are more prevalent in preterm neonates and in breast-fed infants. Vitamin K deficiency can account for vitamin K deficiency bleeding (VKDB) which occurs in 3 forms--early, classic and late. Vitamin K should be administered to all neonates at birth or immediately afterwards. However, the protocols for administration (route of administration, dosage, number of doses) remain a subject of discussion. Oral administration of a single dose of vitamin K protects against classical and early VKDB, but is less effective than intramuscular (IM) prophylaxis for the prevention of late VKDB. Although an increased risk of solid tumour, associated vitamin K administration, can be definitively excluded, a low potential risk of lymphoblastic leukaemia in childhood can not be ruled out. For formula-fed neonates without risk of haemorrhage, a 2 mg oral dose of vitamin K at birth, followed by a second 2 mg oral dose between day 2 and 7, is probably sufficient to prevent VKDB. For infants who are exclusively or nearly exclusively breast-fed, weekly oral administration of 2mg (or 25 microg/day) vitamin K after the initial 2 oral doses is justified at completion of breast-feeding. For neonates at high risk of haemorrhage (premature, neonatal disease, birth asphyxia, difficult delivery, any illness which will delay feeding, known hepatic disease, maternal drugs inhibiting vitamin K activity), the first dose must be administered by the IM or slow intravenous route. Doses should be repeated, particularly in premature infants, by a route of administration decided for each dose according to the clinical state of the infant. For infants of mothers treated with drugs inhibiting vitamin K activity, antenatal maternal prophylaxis (10 to 20 mg/day orally for 15 to 30 days before delivery) prevents early VKDB. After neonatal prophylaxis, as for infants at high risk of haemorrhage, doses need to be repeated at a rate and route of administration decided for each dose, according to the clotting factor profile specific for each infant.

Plasma concentrations after intravenous administration of phylloquinone (vitamin K(1)) in preterm and sick neonates

Vitamin K prophylaxis usually is administered orally or intramuscularly, but in neonatal intensive care oral administration might not be feasible and intramuscular administration is not general practice in very small infants. No data are available about plasma levels after intravenous administration of vitamin K to neonates. Therefore, we investigated plasma levels in 18 infants: 14 preterms with a birthweight of 1785+/-648 g and 4 sick newborns with a birth-weight of 3167+/-510 g after administration of a single dose of 0.3+/-0.1 mg/kg phylloquinone (vitamin K(1)) (Konakion MM((R)), Roche) intravenously after birth. Blood was collected 22.9+/-18.4 hours after intravenous administration of vitamin K(1). In 10 neonates a second sample was obtained 111.8+/-49.1 hours after the first vitamin K(1) administration. Gas chromatography-mass spectrometry (GC-MS) was used as the method for determination of vitamin K(1). The measured plasma concentration after intravenous administration of vitamin K(1) was 191.3+/-102.6 ng vitamin K in the first sample /mL in the first sample and 98.7+/-75.2 ng vitamin K(1)/mL in the second samples. These results are similar to those described in newborns after oral administration of 3 mg vitamin K(1) and after intramuscular administration of 1.5 mg vitamin K(1). In conclusion, the recommendation of the producer to give 0.4 mg/kg of vitamin K intravenously to neonates, in whom oral or intramuscular administration is not feasible, seems to be rational.

Critical windows of exposure for children's health: cancer in human epidemiological studies and neoplasms in experimental animal models

In humans, cancer may be caused by genetics and environmental exposures; however, in the majority of instances the identification of the critical time window of exposure is problematic. The evidence for exposures occurring during the preconceptional period that have an association with childhood or adulthood cancers is equivocal. Agents definitely related to cancer in children, and adulthood if exposure occurs in utero, include: maternal exposure to ionizing radiation during pregnancy and childhood leukemia and certain other cancers, and maternal use of diethylstilbestrol during pregnancy and clear-cell adenocarcinoma of the vagina of their daughters. The list of environmental exposures that occur during the perinatal/postnatal period with potential to increase the risk of cancer is lengthening, but evidence available to date is inconsistent and inconclusive. In animal models, preconceptional carcinogenesis has been demonstrated for a variety of types of radiation and chemicals, with demonstrated sensitivity for all stages from fetal gonocytes to postmeiotic germ cells. Transplacental and neonatal carcinogenesis show marked ontogenetic stage specificity in some cases. Mechanistic factors include the number of cells at risk, the rate of cell division, the development of differentiated characteristics including the ability to activate and detoxify carcinogens, the presence of stem cells, and possibly others. Usefulness for human risk estimation would be strengthened by the study of these factors in more than one species, and by a focus on specific human risk issues.

Measurement of DNA damage by the comet assay in rat embryos grown in media containing high concentrations of vitamin K(1)

It has been suggested that vitamin K(1) (phylloquinone) can cause genetic damage in rapidly dividing cells and that this should be considered in the risk/benefit analysis of the prophylactic use of vitamin K(1) in the newborn. Usual intramuscular administration of 1mg of vitamin K(1) to the newborn gives peak plasma levels of 1-2 microg/ml (approximately 2-4 microM). To investigate the possible harmful effects of high concentrations of vitamin K(1), rat embryos undergoing rapid cell division in the organogenic period were cultured for 46 hours in rat sera containing either 1, 10 or 100 microg of added vitamin K(1) per ml (2, 22 or 222 microM). At the end of the culture period the embryos were dissociated and the cells examined for evidence of DNA damage using the alkaline version of the comet assay. Control embryos were cultured in sera without added vitamin K(1) and positive controls were control embryos exposed to hydrogen peroxide at the end of the culture period. The results did not show any evidence of DNA damage in the vitamin K(1) exposed embryos. The positive controls showed a significant increase in tail length, moment and inertia. In conclusion, under the experimental conditions used, high concentrations of vitamin K(1) did not induce primary DNA damage in cells from rat embryos grown in vitro.

Six years' experience of prophylactic oral vitamin K

AIMS

The ability of oral vitamin K to eliminate all risk of vitamin K deficiency bleeding during the first three months of life was studied.

METHODS

Babies (n=182,000) in the north of England judged well enough to be offered milk within 12 hours of birth were given 1 mg of phytomenadione (vitamin K(1)) suspended in a medium chain triglyceride oil by mouth at delivery between 1993 and 1998. The parents of those who were breastfed were given a further three doses to give to the baby once every two weeks after discharge.

RESULTS

Four breastfed babies developed late vitamin K deficiency bleeding. In two, staff failed to follow policy guidelines, and in two there was undiagnosed alpha(1) antitrypsin deficiency. Audit suggested that 93% of breastfed babies had all four doses, as advised.

CONCLUSIONS

An oral product that parents can administer themselves would be popular if licensed, but the total dose offered may need to be more than in this study if babies with undiagnosed liver disease are to be protected.

Alpha1-antitrypsin deficiency with fatal intracranial hemorrhage in a newborn

A 4-week-old boy had a fatal intracranial hemorrhage resulting from vitamin K deficiency. The infant had received no vitamin K prophylaxis and was exclusively breastfed. At autopsy, examination of the liver showed cholestasis and fibrosis. DNA was isolated from a blood spot on a Gutherie sample card obtained from the infant for routine metabolic screening. This DNA was used for alpha1-antitrypsin genotyping studies. Genotyping studies identified homozygosity for the point mutation 9989G-->A, confirming a diagnosis of alpha1-antitrypsin deficiency (ZZ phenotype), and resulted in appropriate screening of siblings born after this child's death. Alpha1-antitrypsin deficiency should be considered in the differential diagnosis of infants with late hemorrhagic disease of the newborn. Use of blood from the metabolic screening card as a source of DNA allowed confirmation of this diagnosis after the infant's death.

Vitamin K status of lactating mothers and their infants

Vitamin K deficiency remains a world-wide problem in the newborn. Vitamin K traverses the placenta from mother to infant very poorly and is present only in very low concentrations in human milk. Thus, it is not surprising that the newborn infant has undetectable vitamin K serum levels with abnormal amounts of the coagulation proteins and undercarboxylated prothrombin. Hemorrhagic disease of the newborn, secondary to vitamin K deficiency, remains largely a disease of breastfed infants. Lactating mothers easily achieve the recommended dietary allowance for vitamin K (1 microg kg(-1) d(-1)) and the breast milk concentration is readily increased by increasing maternal vitamin K intake. Breastfed infants do not receive the recommended vitamin K intake via human milk. To prevent vitamin K deficiency in the newborn, intramuscular or oral vitamin K prophylaxis is necessary.

Oral versus intramuscular phytomenadione: safety and efficacy compared

Oral and intramuscular phytomenadione (vitamin K1) prophylaxis became an issue following the report of a potential carcinogenic effect of intramuscular but not oral phytomenadione prophylaxis. There is increasing evidence, however, that oral phytomenadione prophylaxis is less effective for the prevention of late vitamin K deficiency bleeding (VKDB) than intramuscular prophylaxis. Following a report of an increased cancer risk after intramuscular phytomenadione, a series of papers on this issue appeared. Although an increased risk for solid tumours could almost certainly be excluded, a potential risk for acute lymphatic leukaemia in childhood could not be ruled out definitively. Almost all cases of late VKDB are preventable with intramuscular phytomenadione prophylaxis administered once at birth, whereas a single oral dose given at birth is much less effective. Repeated oral phytomenadione doses given to breast-fed infants either weekly (1 mg) or daily (25 microg) seem to be as effective as intramuscular phytomenadione prophylaxis. The efficacy of 3 oral 2mg doses with the new mixed micellar preparation ('Konakion MM') remains to be established. Although a number of studies have failed to confirm a cancer risk with phytomenadione, these studies have been unable to rule out a risk definitely because absence of evidence is not evidence of absence. A meta-analysis of the available studies might provide 95% confidence intervals narrow enough to exclude even a small cancer risk with some certainty. Oral prophylaxis will probably be as safe as the intramuscular prophylaxis if given daily (25 microg) or weekly (1 mg).

Prevention of vitamin K deficiency bleeding in newborns

Newborn babies are born vitamin K deficient; however, the deficiency is not sufficiently severe to cause a vitamin K deficiency coagulopathy and haemorrhagic disease of the newborn (HDN). Severe vitamin K deficiency can develop quickly in breast-fed newborns and can result in the appearance of classic HDN during the first week of life or late HDN during the first 2 months of life. Both forms of the disease can be severe, causing brain damage and death. Classic and late HDN are prevented by the intramuscular administration of vitamin K at birth. Oral prophylaxis prevents classic HDN but is ineffective in preventing late HDN. Despite proven effectiveness of intramuscular vitamin K prophylaxis there have been concerns about the need for, and safety of, this therapy. This review provides evidence that there is need for intramuscular vitamin K prophylaxis for all babies in order to eradicate haemorrhagic disease of the newborn and concludes that there is no evidence that this therapy is harmful.

A new mixed micellar preparation for oral vitamin K prophylaxis: randomised controlled comparison with an intramuscular formulation in breast fed infants

OBJECTIVE

To compare a new oral preparation of vitamin K1 (Konakion MM) containing lecithin and glycocholic acid with a standard intramuscular (IM) preparation during the first 8 weeks of life in exclusively breast fed infants.

METHODS

Infants were randomised at birth to the IM group (1 mg vitamin K) or the oral group (2 mg given at birth and repeated at 7 and 30 days of life). Prothrombin time (INR), plasma vitamin K1, and PIVKA II (undercarboxylated prothrombin) were monitored at 14, 30, and 56 days of age.

RESULTS

Seventy nine infants were randomised to the oral group and 77 to the IM group. Sixty seven infants in each group completed eight weeks of the study. Prothrombin times did not differ between the two groups. Mean (SD) plasma vitamin K1 values (in ng/ml) decreased in both groups over time, but were higher in the oral group at 14 and 56 days: 2.0 (1.6) v 1.3 (1.1) at 14 days; 0.5 (0.3) v 0.5 (0.7) at 30 days; and 0.5 (0.8) v 0.2 (0.2) at 56 days of life. PIVKA II was raised (> or = 0.1 AU/ml) in cord blood in 47% of the infants. By 14 days, only one infant in each group had a raised PIVKA II value and both of these initially had high concentrations of PIVKA II in cord blood. At 30 days, there were no raised PIVKA II values. At 56 days, there were no raised PIVKA II values in the oral group, although three infants in the IM group had raised values.

CONCLUSIONS

Plasma vitamin K concentrations were at least equal or significantly higher in babies given oral vitamin K supplements compared with IM treated babies at the time points measured. Through the first 8 weeks of life, multiple doses of the new oral preparation maintain haemostasis and vitamin K status in breast fed infants at least equal to that of the intramuscular preparation.

Leukaemia and non-Hodgkin's lymphoma in children and young adults: are prenatal and neonatal factors important determinants of disease?

A medical record-based study of leukaemia and non-Hodgkin's lymphoma diagnosed before the age of 30 years was carried out at three hospitals in the south of England. Findings for 177 cases and 354 age- and sex-matched controls are presented here. For documented viral infection in pregnancy, the odds ratio (OR) was 6.0 [95% confidence interval (CI) 1.2-29.7] for leukaemia and infinity (95% CI 1.24-infinity) for non-Hodgkin's lymphoma. Mothers of leukaemic cases were more likely to be anaemic, the OR for a pregnancy haemoglobin below 10 g being 3.8 (95% CI 1.3-11.1). An association with birthweight was found for acute myeloid leukaemia, the OR for birthweights > 3500 g being 6.2 (95% CI 1.3-29.8). Further, the preceding siblings of those diagnosed with any form of leukaemia were also more likely to weigh > 3500 g at birth (OR 2.2; 95% CI 1.1-4.4). Overall, leukaemic cases appeared to be comparatively robust at birth with respect to other indicators of well-being, the ORs for jaundice, phototherapy, admission to special care nursery and neonatal intensive care all being less than 1.0. Further, no relation between childhood leukaemia and neonatal administration of intramuscular vitamin K was noted (OR 0.6, 95% CI 0.3-1.4; for acute lymphoblastic leukaemia diagnosed between the ages of 1 and 6 years).