The Importance of Vitamin K During Pregnancy

Vitamin K is found mainly in green leafy vegetables, although it can also be produced endogenously through the action of the intestinal microbiota. Today, we'll take a look at the importance of vitamin K during pregnancy.
The Importance of Vitamin K During Pregnancy

Last update: 28 April, 2021

Vitamin K is a nutrient that can be produced by the bacteria that live in the intestine. It has the ability to affect blood coagulation, so experts consider it an important element when assessing cardiovascular status. Below, we’re going to tell you about the importance of vitamin K during pregnancy.

Before we begin, we must point out that, during pregnancy, nutritional needs increase slightly. Above all, it’s essential to increase the intake of certain vitamins and minerals in order to ensure the proper development of the fetus.

 The Importance of Vitamin K During Pregnancy

Importance of vitamin K

As we mentioned above, vitamin K is responsible for increasing the blood’s ability to clot. Under normal conditions, this is advantageous, as it improves wound recovery. However, in a situation of treatment with anticoagulants, it’s important to be careful regarding the supply of this nutrient.

At the same time, this vitamin has the capacity to help in the formation of tissues and bones. According to a study in the journal Clinical Cases in Mineral and Bone Metabolism, regular intake of the nutrient is capable of helping to ensure greater bone density. This process could be key to the prevention of osteoporosis.

However, to prevent the loss of bone mineral density, it’s best to practice regular strength exercises, as well as calcium and vitamin D intake. We mustn’t forget that this problem is quite prevalent in women, especially after menopause.

Sources of vitamin K

We can ensure adequate levels of vitamin K in the body through the intake of green leafy vegetables. In this sense, spinach, kale, chard, or cruciferous vegetables are a source of the nutrient. In addition, it’s possible to synthesize this element within the digestive tract thanks to the action of intestinal bacteria.

However, you should note that alterations in the composition of the microbiota could affect the ability of microorganisms to produce vitamin K. Therefore, it’s best to include both fiber and probiotics in the regular diet. This ensures good bacterial biodiversity.

Vitamin K in pregnancy

Vitamin K is a particularly important nutrient for pregnant women. Thanks to its anticoagulant properties, it helps prevent bleeding in the fetus, which could cause miscarriage.

According to research that appeared in the journal Scientific Reports, it may be beneficial to schedule vitamin K supplementation in pregnancy in the case of low levels of vitamin K. However, at present, it’s not one of the most common nutrient supplements  during pregnancy.

Even so, experts recommend considering an increase in its intake in the case of antibiotic treatment over a long period of time. In this situation, synthesis at the intestinal level could decrease, so it would be appropriate to guarantee an extra supply.

Is an excess of this nutrient toxic?

Vitamin K isn’t categorized as a toxic nutrient even if it’s consumed in excess. Its water-soluble nature means that its excess is easily expelled through urine.

However, in situations of over-consumption, it’s possible to experience cellular damage due to the interaction on the formation of glutathione, a powerful antioxidant. Likewise, in excessive dosages, liver damage may occur, since this is the main storage site.

 The Importance of Vitamin K During Pregnancy

An important nutrient in pregnancy

As you’ve seen, vitamin K is a nutrient of great importance during pregnancy. Thanks to it, the appearance of hemorrhages in the fetus that could endanger its survival is prevented. This significantly reduces the risk of miscarriages.

It remains to be clarified whether it’s beneficial to systematize vitamin K supplementation during pregnancy, as studies are still inconclusive. Likewise, we should take into account that this element could also have a beneficial effect on the formation of bone tissue in the fetus.


All cited sources were thoroughly reviewed by our team to ensure their quality, reliability, currency, and validity. The bibliography of this article was considered reliable and of academic or scientific accuracy.

  • Brown B, Wright C. Safety and efficacy of supplements in pregnancy. Nutrition Reviews. Octubre 2020. 78 (10): 813-826.
  • Centros para el Control y Desarrollo de Enfermedades. Preguntas frecuentes: la vitamina K y la inyección de vitamina K al nacer. U. S. Department of Health and Human Services. Octubre 2019.
  • Fusaro M, Mereu MC, Aghi A, Iervasi G, Gallieni M. Vitamin K and bone. Clin Cases Miner Bone Metab. 2017 May-Aug;14(2):200-206. doi: 10.11138/ccmbm/2017.14.1.200. Epub 2017 Oct 25. PMID: 29263734; PMCID: PMC5726210.
  • Kellie F. J. Vitamin K supplementation during pregnancy for improving outcomes. Cochrane Database System Reviews. Junio 2017. CD10920.
  • National Institutes of Health. Office of Dietary Supplements. Vitamin K. U. S. Department of Health and Human Services. Marzo 2021.
  • Shahrook S, Ota E, Hanada N, Sawada K, Mori R. Vitamin K supplementation during pregnancy for improving outcomes: a systematic review and meta-analysis. Sci Rep. 2018 Jul 30;8(1):11459. doi: 10.1038/s41598-018-29616-y. PMID: 30061633; PMCID: PMC6065418.

This text is provided for informational purposes only and does not replace consultation with a professional. If in doubt, consult your specialist.