Vitamin K supplementation during pregnancy for improving outcomes: a systematic review and meta-analysis

Sadequa Shahrook,Nobutsugu Hanada,Kimi Sawada,Rintaro Mori,Erika Ota

doi:10.1038/s41598-018-29616-y

Abstract

To study supplementation effect of vitamin K (VK) alone or combined with other nutrients administered to pregnant women, we searched Cochrane Pregnancy and Childbirth Group’s Trials Register (till 22 January 2016, updated on 28 February 2018) including other resources. Two review authors independently assessed randomised or quasi-randomised controlled trials for inclusion, data extraction, accuracy, and risk of bias. We included older trials from high-income countries (six; 21,493 women-newborns), judged mostly as high or unclear bias risk. We could not assess high-risk e.g. epileptic women, but healthy women (different gestational ages) received varying VK dosages and duration. We meta-analysed neonatal bleeding (RR 1.16, 95% CI 0.59 to 2.29; P = 0.67) and maternal plasma VK1 (MD 2.46, 95% CI 0.98 to 3.93; P = 0.001). We found many outcomes were un-assessed e.g. perinatal death, maternal bleeding, healthcare utilization. Mostly newborns were included where VK found significantly effective for e.g. serum VK (mother-newborn), maternal breast milk VK. Few trials reported neonatal adverse side effects. The GRADE evidence quality was very low i.e. neonatal bleeding, neonatal jaundice, maternal plasma VK1. The intervention was favourable for maternal sera VK1 but remained uncertain for neonatal bleeding and other outcomes. The existing literature gaps warrant future investigations on un-assessed or inadequately reported outcomes.

Highlights

To study supplementation effect of vitamin K (VK) alone or combined with other nutrients administered to pregnant women, we searched Cochrane Pregnancy and Childbirth Group’s Trials Register including other resources
Neonatal prothrombin and partial thromboplastin activities can be improved through VK administration, including reduced incidence and severity of intraventricular haemorrhage (IVH)[26,27], VK had null effect in preventing IVH in a previous review[28]
This review was mainly driven by the need for compilation of systematic evidence on VK deficiency during pregnancy, its beneficial dosages and related morbidities in healthy women including those with epilepsy, malabsorption and other health conditions, as these evidence to date is insufficient

Summary

Introduction

To study supplementation effect of vitamin K (VK) alone or combined with other nutrients administered to pregnant women, we searched Cochrane Pregnancy and Childbirth Group’s Trials Register (till 22 January 2016, updated on 28 February 2018) including other resources. Deficiency of vitamin K (VK) can be critical for pregnant women and especially newborns, possibly resulting in haemorrhage. Neonatal prothrombin and partial thromboplastin activities can be improved through VK administration, including reduced incidence and severity of intraventricular haemorrhage (IVH)[26,27], VK had null effect in preventing IVH in a previous review[28]. The effects of VK on related deficiency, bleeding complications and other adverse outcomes, including its importance, to date have been predominantly assessed for neonates, but not for reproductive aged women, especially in pregnancy. In this review, including all pregnant women, we assessed the impact of VK supplementation compared with none or VK with other nutrients on maternal and neonatal outcomes. Outcomes assessed in another review[28] weren’t considered in our investigation

Methods

Results

Discussion

Conclusion