Miscarriage has become one of the most common complaints that I see in clinical practice. Most of these women are unable to carry past the first trimester. Some of my patients have had anywhere from one to five miscarriages. They are left feeling broken, empty, scared, and hopeless; left wondering “What is wrong with me?”

Unfortunately, many women are not given answers or possible solutions to what might be causing their problem. They are told they can conceive through a carrier, or that they can attempt IVF therapy. This poses a lot of psychological stress due to finances, deciding what route to pursue, and the looming question “What if it doesn’t work?”

I take an alternative approach to addressing these issues. My goal is to pinpoint WHY the body is causing a miscarriage to occur. Now, there may be genetic or anatomical reasons that a pregnancy cannot be maintained, but most of the patients that find me come to see me because all of their lab work was “normal” and doctors don’t know why they’ve miscarried.

A developing baby requires the mother to be healthy and well-nourished. This is because the mother is the main source of nutrition, energy, and protection to the baby. If there are disruptions in the mother’s body, this will also cause disruption to the pregnancy.

For instance, Vitamin D has been heavily researched for its role in pregnancy. The developing baby ONLY gets it’s Vitamin D from its mother and high concentrations of Vitamin D can be found in the umbilical cord. Recent evidence estimates that over 40% of the U.S. population is deficient in Vitamin D. People with darker skin fall at an even greater risk of deficiency with 63% of Hispanic people and 82% of black people are deficient1. The American Pregnancy Association estimates that 40-60% of pregnant women may be deficient in Vitamin D2.

Vitamin D3 is formed in the skin after exposure to UV rays, it can also be acquired through dietary supplementation. Once in circulation, Vitamin D is converted to 25-hydroxyvitamin D (25(OH)D) this conversion primarily occurs in the liver. This form of Vitamin D is then converted into the hormonal form– 1,25-dihydroxyvitamin D3 (1,25(OH)2D) this conversion occurs in the kidneys.

Vitamin D metabolism changes during pregnancy. Fetal levels of 1,25(OH)2D will become twice that of a non-pregnant adult and will continue to rise to a point where in non-pregnant adults, these levels may be considered toxic due to calcium dysregulation3. However, in this gestational state, calcium levels are not yet affected. This suggests that rising Vitamin D levels are not as likely to correlate with the demand for calcium, but for enhanced immune response.

Vitamin D is also a modulator of inflammation3, which means, with adequate levels, inflammation tends to be lower. Low Vitamin D levels are associated with inflammatory diseases like cardiovascular disease, arthritis, MS, cancer and IBD. Reproductive disorders like PCOS and endometriosis are also highly inflammatory conditions. This population of women oftentimes struggle with miscarriages or infertility.

Unfortunately, medical recommendations are not reflecting the most current research, the Institute of Medicine recommends 400-600 IU Vitamin D per day and 0 IU are recommended by the World Health Organization4 stating that there are simply no requirements for Vitamin D during pregnancy.

A study looked at pregnant women supplemented with Vitamin D during pregnancy. They analyzed levels of Vitamin D when pregnant women were dosed with 400 IU, 2000 IU, or 4000 IU daily. It was found that the women receiving 4000 IU had the highest Vitamin D concentrations5. Researchers found that in this group, the women who received the highest amount of Vitamin D had the lowest number of pregnancy complications including: preeclampsia, gestational diabetes, preterm labor, caesarean section births, and infections5.

Another study looked at 1200 women, 47% of these women had sufficient levels (>75 nmol/L) and 53% had insufficient levels (<75 nmol/L). Women with sufficient levels were more likely to achieve pregnancy and live birth compared to those with insufficient concentrations6. They also found that if levels were sufficient prior to conception, there was also a reduced risk of pregnancy loss6.

Another concern around Vitamin D and rising numbers of miscarriage and infertility is lack of sunlight exposure and increased time spent indoors, especially during the COVID-19 pandemic. In patients that I have tested in the last year around 90% of them are deficient. All of my patients that have miscarriages are deficient with some having severely low levels of Vitamin D. Which leads us into Part 2 of the miscarriage series- “HPA Axis Dysfunction and Its Effects on Pregnancy”.

  1. Meltzer DO, Best TJ, Zhang H, Vokes T, Arora V, Solway J. Association of Vitamin D Status and Other Clinical Characteristics With COVID-19 Test Results. JAMA Netw Open. 2020;3(9):e2019722. doi:10.1001/jamanetworkopen.2020.19722
  2. Samimi M, Foroozanfard F, Amini F, et al. Effect of vitamin D supplementation on unexplained recurrent spontaneous abortion: a double-blind randomized control trial. Glob J Health Sci. 2017;9(3):95-102.
  3. Hollis, B., Wagner, C. New insights into the vitamin D requirements during pregnancy.Bone Res 5, 17030 (2017). https://doi.org/10.1038/boneres.2017.30
  4. World Health Organisation. Vitamin D Supplementation in Infants. Geneva: World Health Organisation. 2014.
  5. Hollis, B.W., Wagner, C.L. Vitamin D and Pregnancy: Skeletal Effects, Nonskeletal Effects, and Birth Outcomes. Calcif Tissue Int 92, 128–139 (2013). https://doi.org/10.1007/s00223-012-9607-4
  6. Mumford, S., Garbose, R., Kim, K., Kuhr, D., & Omosigho, O. (2018). Association of preconception serum 25-hydroxyvitamin D concentrations with livebirth and pregnancy loss: A prospective cohort study. The Lancet Diabetes and Endocrinology,6(9), 725-732. doi:https://doi.org/10.1016/S2213-8587(18)30153-0