Six years' experience of prophylactic oral vitamin K

Belgian Consensus Recommendations to Prevent Vitamin K Deficiency Bleeding in the Term and Preterm Infant

Neonatal vitamin K prophylaxis is essential to prevent vitamin K deficiency bleeding (VKDB) with a clear benefit compared to placebo. Various routes (intramuscular (IM), oral, intravenous (IV)) and dosing regimens were explored. A literature review was conducted to compare vitamin K regimens on VKDB incidence. Simultaneously, information on practices was collected from Belgian pediatric and neonatal departments. Based on the review and these practices, a consensus was developed and voted on by all co-authors and heads of pediatric departments. Today, practices vary. In line with literature, the advised prophylactic regimen is 1 or 2 mg IM vitamin K once at birth. In the case of parental refusal, healthcare providers should inform parents of the slightly inferior alternative (2 mg oral vitamin K at birth, followed by 1 or 2 mg oral weekly for 3 months when breastfed). We recommend 1 mg IM in preterm <32 weeks, and the same alternative in the case of parental refusal. When IM is perceived impossible in preterm <32 weeks, 0.5 mg IV once is recommended, with a single additional IM 1 mg dose when IV lipids are discontinued. This recommendation is a step towards harmonizing vitamin K prophylaxis in all newborns.

Refusal of Intramuscular Vitamin K by Parents of Newborns: A Review

In 2019, the American Academy of Pediatrics made public education about intramuscular vitamin K administration at birth a public health priority, partly in response to reports of refusal of intramuscular vitamin K by parents of newborns that led to vitamin K deficiency bleeding (VKDB). We reviewed the literature on the frequency of, reported reasons for, and factors associated with refusal of intramuscular vitamin K, incidence of VKDB in newborns who did not receive intramuscular vitamin K, and use of oral vitamin K to prevent VKDB. Without prophylaxis, estimates of the incidence per 100 000 births of VKDB range from 250 to 1700 for early VKDB and from 10.5 to 80 for late VKDB. The frequency of refusal of intramuscular vitamin K by parents ranged from 0% to 3.2% in US hospitals, up to 14.5% in home births, and up to 31.0% in birthing centers. Reported reasons for refusal were concern of harm from the injection, a desire to be natural, and a belief in alternative methods of prophylaxis. Parents who refused intramuscular vitamin K were more likely to refuse immunizations. Many different regimens were used for orally administered vitamin K; it is not clear which is best, but all are less effective than intramuscular vitamin K. VKDB is rare but can result in either neurologic sequelae or death. In addition to continued surveillance of the frequency of both refusal of intramuscular vitamin K and VKDB, a renewed focus on education of and collaboration with parents is needed to address this major public health threat.

Increasing the dose of oral vitamin K prophylaxis and its effect on bleeding risk

Vitamin K prophylaxis in infancy aims to prevent life-threatening vitamin K deficiency bleeding (VKDB). The Dutch prophylactic oral daily regimen was increased sixfold from 25 to 150 μg because of a high failure rate. To evaluate the efficacy of this new regimen, incidences of intracranial VKDB under both regimens were compared using both general and targeted surveillance. Late VKDB in the general pediatric population was identified by the Netherlands Pediatric Surveillance Unit, between 1 October 2014 and 31 December 2016. Additionally, infants with intracranial vitamin K deficiency bleeding were identified using the Dutch Pediatric Intensive Care Evaluation registry. The incidence of intracranial VKDB as assessed by general and targeted surveillance decreased from 1.6 per 100,000 (95% CI, 0.4-5.1) to 1.3 per 100,000 (95% CI, 0.5-3.2) and from 3.1 per 100,000 live births (95% CI, 1.9-5.0) to 1.2 per 100,000 live births (95% CI, 0.6-2.3), respectively. Median time between consecutive cases in the latter increased from 24 to 154 days (p < 0.001).Conclusion: A sixfold increase in oral vitamin K prophylaxis was associated with a surprisingly modest reduction in the incidence of intracranial VKDB, indicating that factors other than the dose need addressing to improve efficacy. What is Known: • The efficacy of intramuscular vitamin K prophylaxis is threatened by an increasing number of parents opting out. • Oral prophylaxis represents an attractive and less invasive alternative but is inferior, especially in infants with malabsorption of vitamin K due to cholestasis. What is New: • Increasing the daily oral dose of vitamin K sixfold had a surprisingly modest effect on the incidence of late vitamin K deficiency bleeding. • This finding indicates that factors other than the dose must play an important role.

Intracranial haemorrhage is linked to late onset vitamin K deficiency in infants aged 2-24 weeks

AIM

Late vitamin K deficiency bleeding (VKDB) can be serious and manifest as early onset intracranial haemorrhage (ICH). This study aimed to determine the frequency of ICH in relation to vitamin K deficiency and the outcome in infants aged two to 24 weeks.

METHOD

A hospital-based study was conducted in two main tertiary hospitals in Cairo, Egypt, from May 2011 to May 2012 with 40 patients with ICH and 50 age-matched controls without ICH.

RESULTS

Forty patients with ICH were recruited, 19 were excluded for clinical reasons and the remaining 21 had a significantly low vitamin K level. Exclusive breast feeding (81% of patients), diarrhoea lasting more than 1 week (38.1%) and antibiotic consumption within a week before the development of ICH (57.1%) were more common in the patients than in the control group (p value>0.05, <0.01 and <0.01, respectively).

CONCLUSION

A high frequency of ICH due to late VKDB was reported in Egyptian infants aged two to 24 weeks, with poorer outcomes than international studies. A national survey is required to evaluate the timing and protective value of a second booster vitamin K dose to reduce ICH, especially in high-risk patients in this age group.

Late haemorrhagic disease of the newborn

BACKGROUND

Late haemorrhagic disease of the newborn (HDN) can occur owing to a lack of vitamin K prophylaxis, as a manifestation of an underlying disorder or idiopatically from the 8th day to 12 weeks after birth.

METHODS

Eight infants admitted to Kocaeli University Hospital with nine episodes of late HDN between January 2002 and April 2005 were evaluated retrospectively from hospital records.

RESULTS

The median age at presentation was 46 (26-111) days. All the infants were born at full-term to healthy mothers and were exclusively breast-fed. All had an uneventful perinatal history, except one who had meconium aspiration. Four patients had received no vitamin K prophylaxis and another three had uncertain histories. At presentation, six had intracranial bleeding and the remainder had bleeding either from the venepuncture site or the gastro-intestinal tract. The presenting signs and symptoms were irritability, vomiting, bulging or full fontanelle, convulsions and diminished or absent neonatal reflexes. Galactosaemia was detected in a 2-month-old infant with prolonged jaundice. There was no surgery-related mortality or complications but one survived for only 2 days on ventilatory support following surgery. Only one of the six survivors had severe neurological sequelae.

CONCLUSIONS

Late HDN frequently presents with intracranial haemorrhage, leading to high morbidity and mortality. HDN can be the manifestation of an underlying metabolic disorder. Vitamin K prophylaxis of the newborn should be routine in developing countries.

New Zealand surveillance of neonatal vitamin K deficiency bleeding (VKDB): 1998-2008

AIM

To undertake surveillance of vitamin K deficiency bleeding (VKDB) from 1998, through the transition to a new single licensed vitamin K preparation in 2001, to 2008.

METHODS

VKDB was listed with other rare conditions on the card sent monthly to registered specialist paediatricians by the New Zealand Paediatric Surveillance Unit with a request to indicate whether or not a case had been seen in the previous month. Those notifying a case were sent a two-page questionnaire. The main outcome measures were incidence of VKDB of early (first day of life), classic (days 2-7) and late-onset (day 8 to 6 months) type; related morbidity and mortality; receipt of vitamin K; and predisposing factors.

RESULTS

Response rate of return of surveillance cards was high, averaging 94.5%. There were 35 notifications of which 23 were valid cases. Seventeen cases met criteria for confirmed VKDB, two for 'probable' and four for 'possible'. There were eight confirmed classic cases with an overall incidence of 1.24 (95% confidence interval 0.54-2.45) per 100,000 births; none had received vitamin K prophylaxis, seven were fully breastfed and all fully recovered. There were nine confirmed late-onset cases with an overall incidence of 1.40 (95% confidence interval 0.64-2.65) per 100,000 births; eight had received no vitamin K, eight were fully breastfed, six had liver disease, four suffered an intracranial haemorrhage and one died.

CONCLUSIONS

In New Zealand, VKDB is virtually confined to fully breastfed infants not given vitamin K at birth. Late-onset cases were frequently associated with liver disease.

Evaluation of the acceptability of a new oral vitamin K prophylaxis for breastfed infants

AIM

The aim of this study was to investigate the acceptability and tolerability of the oral food supplement Neokay for the prevention of vitamin K deficiency bleeding in newborns.

METHODS

A questionnaire survey was conducted among 45 midwives in which they were asked 10 questions about their use of Neokay, its advantages and disadvantages, and their perceptions of parental attitudes towards this new prophylactic treatment.

RESULTS

During a 6-month period one dose of Neokay was given to 1794 healthy newborns at birth and further daily doses were given to 812 breastfed infants for 3 months. The midwives listed as main advantages ease of administration, no need for prescription or written consent, and transfer of responsibility to parents. As disadvantages, they mentioned possible reduced compliance as a result of the frequency of dosing, decreased parental confidence in breastfeeding and technical issues with packaging.

CONCLUSION

A prophylactic vitamin K dosage regimen of 1 mg oral vitamin K (Konakion MM Paediatric or Orakay) given to all healthy neonates at birth, combined with daily doses of 50 microg Neokay for 3 months for breastfed babies is well tolerated and acceptable to midwives and parents.

Prevention of vitamin K deficiency bleeding in breastfed infants: lessons from the Dutch and Danish biliary atresia registries

OBJECTIVE

Newborns routinely receive vitamin K to prevent vitamin K deficiency bleeding. The efficacy of oral vitamin K administration may be compromised in infants with unrecognized cholestasis. We aimed to compare the risk of vitamin K deficiency bleeding under different prophylactic regimens in infants with biliary atresia.

PATIENTS AND METHODS

From Dutch and Danish national biliary atresia registries, we retrieved infants who were either breastfed and received 1 mg of oral vitamin K at birth followed by 25 microg of daily oral vitamin K prophylaxis (Netherlands, 1991-2003), 2 mg of oral vitamin K at birth followed by 1 mg of weekly oral prophylaxis (Denmark, 1994 to May 2000), or 2 mg of intramuscular prophylaxis at birth (Denmark, June 2000-2005) or were fed by formula. We determined the absolute and relative risk of severe vitamin K deficiency and vitamin K deficiency bleeding on diagnosis in breastfed infants on each prophylactic regimen and in formula-fed infants.

RESULTS

Vitamin K deficiency bleeding was noted in 25 of 30 of breastfed infants on 25 microg of daily oral prophylaxis, in 1 of 13 on 1 mg of weekly oral prophylaxis, in 1 of 10 receiving 2 mg of intramuscular prophylaxis at birth, and in 1 of 98 formula-fed infants (P < .001). The relative risk of a bleeding in breastfed compared with formula-fed infants was 77.5 for 25 microg of daily oral prophylaxis, 7.2 for 1 mg of weekly oral prophylaxis, and 9.3 for 2 mg of intramuscular prophylaxis at birth.

CONCLUSIONS

A daily dose of 25 microg of vitamin K fails to prevent bleedings in apparently healthy infants with unrecognized cholestasis because of biliary atresia. One milligram of weekly oral prophylaxis offers significantly higher protection to these infants and is of similar efficacy as 2 mg of intramuscular prophylaxis at birth. Our data underline the fact that event analysis in specific populations at risk can help to evaluate and improve nationwide prophylactic regimens.

Incidence of late vitamin K deficiency bleeding in newborns in the Netherlands in 2005: evaluation of the current guideline

Vitamin K prophylaxis is recommended to prevent the hazard of haemorrhage caused by vitamin K deficiency in newborns. The present Dutch guideline recommends 1 mg of vitamin K(1) orally at birth, followed by a daily dose of 25 microg of vitamin K(1) from 1 to 13 weeks of age for breastfed infants. Since the introduction of this prophylaxis, the incidence of vitamin K deficiency bleeding (VKDB) has decreased; however, late VKDB is still reported. From 1 January to 31 December 2005, a nationwide active surveillance was performed by the Netherlands Paediatric Surveillance Unit (NSCK) to study the current incidence and aetiology of late VKDB in infants. Six cases could be validated as late VKDB: all were breastfed, one fatal idiopathic intracranial haemorrhage at the age of 5 weeks and five bleedings secondary to an underlying cholestatic liver disease between the age of 3 and 7 weeks. The total incidence of late VKDB and idiopathic late VKDB was calculated to be 3.2 (95% CI: 1.2-6.9) and 0.5 (95% CI: 0-2.9) per 100,000 live births, respectively. With the current Dutch guideline, idiopathic late VKDB is rare but late VKDB secondary to cholestasis still occurs in breastfed infants. Doubling the daily dose of vitamin K(1) to 50 microg, as is comparable to formula-feeding, may possibly prevent VKDB in this group. Further research, however, is needed to prove this hypothesis.

Intracranial haemorrhage due to late onset vitamin K deficiency bleeding in Hanoi province, Vietnam

BACKGROUND

In many developing countries vitamin K prophylaxis is not routinely administered at birth. There are insufficient data to assess the cost effectiveness of its implementation in such countries.

OBJECTIVE

To estimate the burden of intracranial haemorrhage caused by late onset vitamin K deficiency bleeding in Hanoi, Vietnam.

METHODS

Cases of intracranial haemorrhage in infants aged 1-13 weeks were identified in Hanoi province for 5 years (1995-1999), and evidence for vitamin K deficiency was sought. The data were compared with those on vitamin K deficiency bleeding in developed countries and used to obtain an approximation to the incidence of intracranial haemorrhage caused by vitamin K deficiency bleeding in Hanoi.

RESULTS

The estimated incidence of late onset vitamin K deficiency bleeding in infants who received no prophylaxis was unexpectedly high (116 per 100,000 births) with 142 and 81 per 100,000 births in rural and urban areas respectively. Mortality was 9%. Of the surviving infants, 42% were neurologically abnormal at the time of hospital discharge. Identified associations were rural residence, male sex, and low birth weight. A significant reduction in the incidence was observed in urban Hanoi during 1998 and 1999, after vitamin K prophylaxis was introduced at one urban obstetric hospital.

CONCLUSIONS

Vitamin K deficiency bleeding is a major public health problem in Hanoi. The results indicate that routine vitamin K prophylaxis would significantly reduce infant morbidity and mortality in Vietnam and, costing an estimated 87 US dollars (48 pounds, 72 Euro) per disability adjusted life year saved, is a highly cost effective intervention.

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.

Oral mixed micellar vitamin K for prevention of late vitamin K deficiency bleeding

OBJECTIVE

To determine whether the use of mixed micellar vitamin K improves the efficacy of the 3 x 2 mg oral vitamin K prophylaxis schedule.

DESIGN

Nationwide active surveillance for vitamin K deficiency bleeding (VKDB) complemented with two surveys on the use of the mixed micellar preparation in hospitals and by paediatricians.

SETTING AND PATIENTS

Infants in Germany in 1997-2000.

INTERVENTION

Prophylaxis with three oral doses of 2 mg mixed micellar vitamin K.

MAIN OUTCOME MEASURE

Confirmed VKDB between day 8 and week 12 and no condition requiring specific vitamin K supplementation known before the onset of bleeding.

RESULTS

Twenty nine reports met the case definition: seven had not received any vitamin K prophylaxis; for three, vitamin K prophylaxis was unknown; two had insufficient vitamin K prophylaxis for their age; 17 had been given the recommended doses. The mixed micellar preparation had been given to seven, other preparations to nine, and one had been given both. These cases did not differ with respect to the site of bleeding and cholestasis detected at bleeding. Estimates of the use of the mixed micellar preparation in birth hospitals and by paediatricians yielded 1 817 769 newborns exposed to the mixed micellar preparation and 1 320 926 newborns exposed to other preparations. The rate of late VKDB was 0.44/100 000 (95% confidence interval (CI) 0.19 to 0.87) in children given mixed micellar vitamin K compared with 0.76/100 000 (95% CI 0.36 to 1.39) in children given other preparations.

CONCLUSION

Mixed micellar vitamin K did not significantly improve the efficacy of the 3 x 2 mg oral vitamin K prophylaxis schedule.

Intestinal absorption of mixed micellar phylloquinone (vitamin K1) is unreliable in infants with conjugated hyperbilirubinaemia: implications for oral prophylaxis of vitamin K deficiency bleeding

OBJECTIVE

To compare the pharmacokinetics and efficacy of oral versus intravenous mixed micellar vitamin K prophylaxis in infants with cholestatic liver disease, a known risk factor for vitamin K deficiency bleeding.

DESIGN

Prospective randomised controlled study.

SETTING

Paediatric Liver Unit.

PATIENTS

Forty four infants less than 6 months of age with conjugated hyperbilirubinaemia.

MAIN OUTCOME MEASURES

Serum concentrations of vitamin K(1) and undercarboxylated prothrombin (PIVKA-II; a sensitive functional indicator of vitamin K status) before and for up to four days after a single dose of mixed micellar K(1) 1 mg intravenously or 2 mg orally. Comparison of K(1) levels 24 hours after oral K(1) with those from 14 healthy newborns given the same dose.

RESULTS

At admission, 18 infants (41%) had elevated levels of serum PIVKA-II and eight (18%) had low K(1) concentrations, indicative of subclinical vitamin K deficiency. Median serum K(1) concentrations were similar in the oral and intravenous groups at baseline (0.92 v 1.15 ng/ml), rising to 139 ng/ml six hours after intravenous K(1) but to only 1.4 ng/ml after oral administration. In the latter group, the low median value (0.95 ng/ml) and wide range (< 0.15-111 ng/ml) of serum K(1) compared unfavourably with the much higher levels (median 77, range 11-263 ng/ml) observed in healthy infants given the same oral dose, and suggested impaired and erratic intestinal absorption in cholestatic infants. The severity of malabsorption was such that only 4/24 (17%) achieved an incremental rise in serum K(1) > 10 ng/ml.

CONCLUSIONS

The intestinal absorption of mixed micellar K(1) is unreliable in infants with conjugated hyperbilirubinaemia. Given the strong association between cholestasis and late vitamin K deficiency bleeding, these data provide an explanation for the failure of some oral vitamin K(1) prophylaxis regimens in infants with latent cholestasis.

Vitamin K--what, why, and when

Policies for giving babies vitamin K prophylactically at birth have been dictated, over the last 60 years, more by what manufacturers decided on commercial grounds to put on the market, than by any informed understanding of what babies actually need, or how it can most easily be given. By a pure fluke a 1 mg IM dose, designed to prevent early vitamin deficiency bleeding ("haemorrhagic disease of the newborn") has been found to protect against late deficiency bleeding-a condition unrecognised at the time this policy took hold. Alternative strategies for oral prophylaxis are now opening up (see pp 109 and 113), but these are also, at the moment, dictated more by what the manufacturers choose to provide than by what would make for ease of delivery either in poor countries, or in the developed world.

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 deficiency and D-dimer levels in the intensive care unit: a prospective cohort study

Patients in the intensive care unit (ICU) are at risk for the development of vitamin K deficiency. We sought to determine the frequency of this deficiency by performing a prospective cohort study in which patients were screened for vitamin K deficiency on ICU admission and every other day thereafter. Vitamin K deficiency was diagnosed by a functional coagulation factor II to Echis factor II ratio < 0.70. Activity of the coagulation cascade was measured by D-dimer. In total, 40 patients were enrolled into the study. Seven of the patients had ratios < 0.70 on the day of admission to the ICU, and three patients developed ratios < 0.70. Thus, 10 of 40 patients (25%; 95% confidence interval, 12-38%) had vitamin K deficiency. Two patients developed coagulopathy, as indicated by an International Normalized Ratio of more than 1.4. D-dimer levels were elevated in 86 of 111 samples. We conclude that vitamin K deficiency is common among critically ill patients, particularly on admission to the ICU. Our findings suggest that additional clinical research is warranted to determine whether vitamin K supplementation on admission to the ICU reduces the risk of ICU-acquired vitamin K deficiency and its attendant complications over the course of the ICU stay.

Prophylactic vitamin K for vitamin K deficiency bleeding in neonates

BACKGROUND

Vitamin K deficiency can cause bleeding in an infant in the first weeks of life. This is known as Hemorrhagic Disease of the Newborn (HDN). HDN is divided into three categories: early, classic and late HDN. Early HDN occurs within 24 hours post partum and falls outside the scope of this review. Classic HDN occurs on days one to seven; common bleeding sites are gastrointestinal, cutaneous, nasal and from a circumcision. Late HDN occurs from week 2-12; the most common bleeding sites are intracranial, cutaneous, and gastrointestinal. Vitamin K is commonly given prophylactically after birth for the prevention of HDN, but the preferred route is uncertain.

OBJECTIVES

To review the evidence from randomized trials in order to determine the effectiveness of vitamin K prophylaxis in the prevention of classic and late HDN. Main questions are: Is one dose of vitamin K, given after birth, able to significantly reduce the incidence of classic and late HDN? Is there a significant difference between the oral route and the intramuscular route in preventing classic and late HDN? Are multiple oral doses of vitamin K, given after birth, able to significantly reduce the incidence of classic and late HDN?

SEARCH STRATEGY

The standard search strategy of the Cochrane Neonatal Review Group was used.

SELECTION CRITERIA

All trials using random or quasi-random patient allocation, in which methods of vitamin K prophylaxis in infants were compared to each other, placebo or no treatment, were included.

DATA COLLECTION AND ANALYSIS

Data were extracted independently by each author and were analysed with the standard methods of the Cochrane Collaboration and its Neonatal Review Group, using relative risk, risk difference and weighted mean difference.

MAIN RESULTS

Two eligible randomized trials, each comparing a single dose of intramuscular vitamin K with placebo or nothing, assessed effect on clinical bleeding. One dose of vitamin K reduced clinical bleeding at 1-7 days, including bleeding after circumcision, and improved biochemical indices of coagulation status. Eleven additional eligible randomized trials compared either a single oral dose of vitamin K with placebo or nothing, a single oral with a single intramuscular dose of vitamin K, or three oral doses with a single intramuscular dose. None of these trials assessed clinical bleeding. Oral vitamin K improved biochemical indices of coagulation status at 1-7 days. There was no evidence of a difference between the oral and intramuscular route in effects on biochemical indices of coagulation status. A single oral compared with a single intramuscular dose resulted in lower plasma vitamin K levels at two weeks and one month, whereas a 3-dose oral schedule resulted in higher plasma vitamin K levels at two weeks and at two months than did a single intramuscular dose.

REVIEWER'S CONCLUSIONS

A single dose (1.0 mg) of intramuscular vitamin K after birth is effective in the prevention of classic HDN. Either intramuscular or oral (1.0 mg) vitamin K prophylaxis improves biochemical indices of coagulation status at 1-7 days. Neither intramuscular nor oral vitamin K has been tested in randomized trials with respect to effect on late HDN. Oral vitamin K, either single or multiple dose, has not been tested in randomized trials for its effect on either classic or late HDN.