<\/p>\n\n\n\n
If you\u2019ve never considered how important vitamin D is for your fertility and during pregnancy, you might be shocked by how much this \u201csunshine vitamin\u201d affects far more than just your skin tone. From bone health to blood sugar stabilization, and blood pressure management to mood, vitamin D is crucial for every woman, especially those trying to conceive.<\/p>\n\n\n\n
But what levels are optimal for functional fertility? Should every woman take a supplement, regardless of her health status and geographic location? What happens when levels are sub-optimal? Let\u2019s discuss that and more below.<\/p>\n\n\n\n
Vitamin D got its nickname, \u201cthe sunshine vitamin,\u201d because it\u2019s the only nutrient our bodies derive from the sun. Like Vitamins A, E, and K, Vitamin D is characterized as a fat-soluble vitamin, meaning that it \u201ccan dissolve in fats and oils,\u201d according to the National Cancer Institute<\/a>. The most common form of Vitamin D (there are actually six different kinds<\/a>!) is synthesized from cholesterol [1]. Vitamin D is primarily stored in the liver, with small amounts stored in fatty tissue throughout the body.<\/p>\n\n\n\n You\u2019re perhaps aware that Vitamin D is vital for proper absorption of calcium and phosphorus in the body (this is partly why milk, which is naturally high in calcium, is often fortified with Vitamin D). Additionally, Vitamin D is also a steroid hormone that plays a key role in reproductive health<\/a> [2].\u00a0<\/p>\n\n\n\n When your skin is exposed to the sun, the cholesterol in your skin absorbs Vitamin D and converts it into usable forms. From there, Vitamin D:<\/p>\n\n\n\n This is just scratching the surface of how Vitamin D works throughout your body. Let\u2019s take a closer look at what it means specifically for fertility and pregnancy.<\/p>\n\n\n\n Vitamin D has receptor sites throughout the body, including on or within the reproductive organs, tissues, and cells in both men and women [4].<\/a> Vitamin D receptors communicate with the hypothalamus in the brain, which in turn regulates production of progesterone, estradiol, and estrone. (For reference, estradiol is the primary form of estrogen secreted during the fertile years, whereas estrone is secreted after menopause<\/a>.) Vitamin D levels also influence follicle-stimulating hormone (FSH) production and the maturation of individual follicles [5]. <\/p>\n\n\n\n During the menstrual cycle, Vitamin D plays a significant role in the follicular phase<\/a>, as estrogen levels rise and a follicle matures in preparation for ovulation. Then, after ovulation, Vitamin D is needed to sustain a healthy corpus luteum<\/a>, which is responsible for progesterone production in the luteal phase<\/a> of the menstrual cycle, plus early on in a pregnancy [6].<\/p>\n\n\n\n During the menstrual cycle, Vitamin D plays a significant role in the follicular phase, as estrogen levels rise and a follicle matures in preparation for ovulation. Then, after ovulation, Vitamin D is needed to sustain a healthy corpus luteum, which is responsible for progesterone production in the luteal phase of the menstrual cycle, plus early on in a pregnancy.<\/p><\/blockquote><\/figure>\n\n\n\n You can see from the above that Vitamin D is clearly integral to female hormone production, and without it, how female fertility might suffer! In fact, low Vitamin D is linked to:<\/p>\n\n\n\n Despite Vitamin D\u2019s importance to the female reproductive system, research<\/a> yields conflicting results on whether simply supplementing Vitamin D will improve fertility outcomes [4]. When you\u2019re healthy and have no underlying conditions, taking more Vitamin D may<\/em> improve your fertility. But if you have an underlying health condition like PCOS or endometriosis, supplementing Vitamin D alone may not be enough to overcome infertility. <\/p>\n\n\n\n We also can\u2019t forget that men are necessary for making a baby, and Vitamin D dramatically affects men\u2019s fertility, too. Vitamin D is crucial for spermatogenesis <\/a>(the process of creating sperm) and is believed to influence sperm motility and function [7]. Additionally, more Vitamin D is associated with higher testosterone levels [8].<\/a> <\/p>\n\n\n\n However, similar to female fertility, evidence suggests a positive relationship between the Vitamin D levels and testosterone in already-healthy<\/em> men [4]. In contrast, for men with underlying health conditions, supplementation with Vitamin D alone may not meaningfully impact testosterone levels. This suggests that getting to the root cause of infertility is more complex than simply increasing one\u2019s serum (the amount circulating in the blood) Vitamin D levels. <\/p>\n\n\n\n Once your baby is conceived, Vitamin D plays a role<\/a> in \u201cdecidualization, implantation, expression of human placental lactogen (hPL), secretion of human chorionic gonadotropin (hCG), progesterone and estrogen levels, calcium-uptake in the placenta and the immune responses of the placenta\u201d [4].<\/p>\n\n\n\n As your baby develops, Vitamin D is also crucial for the growth and development of his or her bones, organs, and tissues. And if your Vitamin D intake isn\u2019t sufficient, your body will actually pull from your Vitamin D stores to supply your baby\u2019s needs. <\/p>\n\n\n\n Ongoing research is likewise exploring the possibility of a link between Vitamin D and miscarriage rates [2][9].<\/a> Low Vitamin D is also connected to pregnancy complications for the mother and baby. For the mother, low Vitamin D levels are specifically associated with higher incidence<\/a> of high blood pressure (gestational hypertension), gestational diabetes, preeclampsia, preterm birth, and postpartum mood disorders [4]. For the baby<\/a>, low Vitamin D levels are associated with low birth weight, low calcium levels, poor post-birth growth, fragile bones, and an increased risk of developing autoimmune disorders in the future [10]. <\/p>\n\n\n\n But what is a normal level of Vitamin D, anyway? In the United States, the standard Vitamin D level is 20 ng\/mL to 60 ng\/mL, with optimal levels ranging from 40 ng\/mL to 70 ng\/mL. <\/strong>And the standard recommended daily allowance (RDA) per person is 600 IU\/day.<\/a> I differentiate standard vs. optimal because there is lack of clarity in the research literature on what is optimal for fertile and pregnant women vs. what is acceptable for the general population. <\/p>\n\n\n\n Lily Nichols, RDN, writes, \u201cThe Institute of Medicine sets the RDA for vitamin D at 600 IU\/day; however, several studies have found this level of intake to be insufficient to maintain normal vitamin D levels throughout pregnancy.\u201c (See Real Food For Pregnancy, Ch 6).<\/p>\n\n\n\n As with any lab value, your physiology will determine how much vitamin D you need for thriving fertility and potential pregnancy. Therefore, consider the specific lab values with caution and investigate further for your particular situation. <\/p>\n\n\n\n Strikingly, it\u2019s believed that nearly 40% of the population is Vitamin D deficient.<\/a> If you don\u2019t get enough exposure to sunlight, don\u2019t eat foods high in Vitamin D, have kidney problems, or have trouble with digestive tract absorption (as is the case with<\/a> celiac disease, bariatric surgery, or inflammatory bowel disease), your Vitamin D levels may be low. Though it\u2019s difficult to pin down an \u201cideal\u201d Vitamin D level because we all have different needs, there are still recognizable signs of deficiency. <\/p>\n\n\n\n Common signs of vitamin D deficiency include:<\/p>\n\n\n\n Of course, these symptoms could be caused and\/or exacerbated by a variety of health conditions. That\u2019s why low Vitamin D is rarely a stand-alone issue. As mentioned above, simply supplementing with Vitamin D without<\/em> improving overall health may increase serum Vitamin D levels, but may not affect fertility rates. <\/p>\n\n\n\n The sun is a free and simple source to meet most of your Vitamin D RDA. In fact, 90%<\/a> of our Vitamin D levels come from the sun [11]. Aim for getting out in the sun midday, between 10 am and 4 pm. Although the time required will vary depending on each person, 5-30 minutes should be sufficient. Then, if you feel the need to put on sunscreen or protective clothing, you can rest assured that you’ve gotten your Vitamin D for the day.<\/p>\n\n\n\n Of course, the season of the year, region, cloud cover, fog, length of day, amount of melanin in your skin, and sunscreen can all affect just how much Vitamin D you get from the sun. If you\u2019re unable to soak up some rays for 5-30 minutes per day at least a few times per week, it may be wise to focus next on food and supplements. <\/p>\n\n\n\n The best food sources of Vitamin D are found in oily fish; think cod liver oil, trout, and salmon. But you can also find a decent amount in mushrooms, fortified milks, and egg yolks. As with all food, it’s important to source the best food you can afford. Although processed foods may contain higher levels of fortified Vitamin D, there are several other concerns with processed foods<\/a> that you may want to consider for your overall health. <\/p>\n\n\n\n If the sun is hard to come by and you can\u2019t get your hands on fresh fish, supplements may be your next best bet. When sourced well, supplements<\/a> can help fill the gaps in your Vitamin D intake. Vitamin D2 supplements are derived from mushrooms or yeast<\/a>, whereas Vitamin D3 supplements are derived from animal products<\/a>. Although both are metabolized and function similarly, there is some evidence<\/a> suggesting that Vitamin D3 increases serum levels to a greater extent and maintains them more effectively than D2.<\/p>\n\n\n\n Lily Nichols, RDN, recommends consulting with your healthcare team to determine your specific Vitamin D level before starting a supplement. That way, you can periodically check your numbers to see if the supplements are right for your specific needs. <\/p>\n\n\n\n As mentioned previously, Nichols believes that current RDA limits are too low for pregnant and nursing mothers and recommends starting with 4000 IU per day, which is more than six times the RDA. (See Real Food for Pregnancy, Chapter 6) This is the case for most prenatal vitamins,<\/a> they may have vitamin D included but the IU is not optimal. <\/p>\n\n\n\n Finally, to optimize vitamin D supplement (or food source) absorption, consider taking it with magnesium, followed by a healthy fat source such as avocado or nuts.<\/p>\n\n\n\n It\u2019s important to note that though toxicity is rare, it can<\/em> occur with high doses of Vitamin D. Vitamin D is a fat-soluble vitamin, which means it isn\u2019t excreted in the urine like water-soluble vitamins. Excess Vitamin D is stored in your fat cells, where it then increases calcium absorption (this is called hypercalcemia).<\/p>\n\n\n\n The National Institutes of Health<\/a> states, \u201cHypercalcemia, in turn, can lead to nausea, vomiting, muscle weakness, neuropsychiatric disturbances, pain, loss of appetite, dehydration, polyuria, excessive thirst, and kidney stones.\u201d For this reason, it\u2019s important to have your Vitamin D levels checked before supplementing beyond whatever is in your multivitamin or prenatal vitamin. <\/p>\n\n\n\n As you can see, Vitamin D is an essential vitamin for both men and women. Without this \u201csunshine vitamin,\u201d many physiological processes suffer, including menstrual health and pregnancy outcomes. If you suspect you have a Vitamin D deficiency, work with your healthcare team to identify the root cause of your deficiency, giving yourself the best chance at improving your overall health and achieving your health goals. <\/p>\n\n\n\nHow the body uses Vitamin D<\/span><\/h3>\n\n\n\n
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Vitamin D and female fertility <\/span><\/h3>\n\n\n\n
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Simply raising Vitamin D levels won\u2019t necessarily correct infertility or other health issues<\/span><\/h3>\n\n\n\n
Vitamin D and male fertility<\/span><\/h3>\n\n\n\n
Vitamin D and pregnancy <\/span><\/h2>\n\n\n\n
Without sufficient Vitamin D, your and your baby\u2019s health are at risk<\/span><\/h3>\n\n\n\n
Normal levels of Vitamin D and RDA during pregnancy<\/span><\/h3>\n\n\n\n
Signs of Vitamin D deficiency<\/span><\/h2>\n\n\n\n
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Sources of Vitamin D<\/span><\/h2>\n\n\n\n
Start with the sun<\/span><\/h3>\n\n\n\n
Eat foods high in Vitamin D<\/span><\/h3>\n\n\n\n
Consider supplements<\/span><\/h3>\n\n\n\n
Can you take too much vitamin D?<\/span><\/h3>\n\n\n\n
The bottom line for vitamin D for fertility and pregnancy <\/span><\/h2>\n\n\n\n
References:<\/span><\/h4>\n\n\n\n[1 ]Demer LL, Hsu JJ, Tintut Y. Steroid Hormone Vitamin D: Implications for Cardiovascular Disease. Circ Res. 2018 May 25;122(11):1576-1585. doi: 10.1161\/CIRCRESAHA.118.311585. PMID: 29798901; PMCID: PMC6122607.<\/p>\n\n\n\n[2] Meng X, Zhang J, Wan Q, et al. Influence of Vitamin D supplementation on reproductive outcomes of infertile patients: a systematic review and meta-analysis. Reprod Biol Endocrinol. 2023 Feb 3;21(1):17. doi: 10.1186\/s12958-023-01068-8. PMID: 36737817; PMCID: PMC9896710.<\/p>\n\n\n\n[3] Argano C, Mirarchi L, Amodeo S, et al. The Role of Vitamin D and Its Molecular Bases in Insulin Resistance, Diabetes, Metabolic Syndrome, and Cardiovascular Disease: State of the Art. Int J Mol Sci. 2023 Oct 23;24(20):15485. doi: 10.3390\/ijms242015485. PMID: 37895163; PMCID: PMC10607188.<\/p>\n\n\n\n[4] V\u00e1rb\u00edr\u00f3 S, Tak\u00e1cs I, T\u0171\u0171 L, Nas K, et al. Effects of Vitamin D on Fertility, Pregnancy and Polycystic Ovary Syndrome-A Review. Nutrients. 2022 Apr 15;14(8):1649. doi: 10.3390\/nu14081649. PMID: 35458211; PMCID: PMC9029121.<\/p>\n\n\n\n[5] Voulgaris, N., Papanastasiou, L., Piaditis, G. et al.<\/em> Vitamin D and aspects of female fertility. Hormones<\/em> 16, 5\u201321 (2017). https:\/\/doi.org\/10.14310\/horm.2002.1715<\/a><\/p>\n\n\n\n[6] Merhi Z, Doswell A, Krebs K, Cipolla M. Vitamin D alters genes involved in follicular development and steroidogenesis in human cumulus granulosa cells. J Clin Endocrinol Metab. 2014 Jun;99(6):E1137-45. doi: 10.1210\/jc.2013-4161. Epub 2014 Mar 14. PMID: 24628555; PMCID: PMC4037738.<\/p>\n\n\n\n[7] Cito G, Cocci A, Micelli E, et al. Vitamin D and Male Fertility: An Updated Review. World J Mens Health. 2020 Apr;38(2):164-177. doi: 10.5534\/wjmh.190057. Epub 2019 May 17. PMID: 31190482; PMCID: PMC7076312.<\/p>\n\n\n\n
References Continued:<\/span><\/h4>\n\n\n\n[8] Monson NR, Klair N, Patel U, et al. Association Between Vitamin D Deficiency and Testosterone Levels in Adult Males: A Systematic Review. Cureus. 2023 Sep 24;15(9):e45856. doi: 10.7759\/cureus.45856. PMID: 37750061; PMCID: PMC10518189.<\/p>\n\n\n\n[9] Tamblyn JA, Pilarski NSP, Markland AD, et al. Vitamin D and miscarriage: a systematic review and meta-analysis. Fertil Steril. 2022 Jul;118(1):111-122. doi: 10.1016\/j.fertnstert.2022.04.017. Epub 2022 May 28. PMID: 35637024.<\/p>\n\n\n\n[10] Mulligan ML, Felton SK, Riek AE, Bernal-Mizrachi C. Implications of vitamin D deficiency in\u00a0pregnancy and lactation. Am J Obstet Gynecol. 2010 May;202(5):429.e1-9. doi: 10.1016\/j.ajog.2009.09.002. Epub 2009 Oct 20. PMID: 19846050; PMCID: PMC3540805.<\/p>\n\n\n\n[11] Schmid A, Walther B. Natural vitamin D content in animal products. Adv Nutr. 2013 Jul 1;4(4):453-62. doi: 10.3945\/an.113.003780. PMID: 23858093; PMCID: PMC3941824.<\/p>\n","protected":false},"excerpt":{"rendered":"\u0412\u0438\u0442\u0430\u043c\u0438\u043d \u0441\u043e\u043b\u043d\u0435\u0447\u043d\u043e\u0433\u043e \u0441\u0432\u0435\u0442\u0430\" \u0438\u043c\u0435\u0435\u0442 \u0440\u0435\u0448\u0430\u044e\u0449\u0435\u0435 \u0437\u043d\u0430\u0447\u0435\u043d\u0438\u0435 \u0432 \u0431\u043e\u043b\u044c\u0448\u0435\u0439 \u0441\u0442\u0435\u043f\u0435\u043d\u0438, \u0447\u0435\u043c \u0432\u044b \u0434\u0443\u043c\u0430\u0435\u0442\u0435.","protected":false},"author":137,"featured_media":23206,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":true,"_kad_blocks_custom_css":"","_kad_blocks_head_custom_js":"","_kad_blocks_body_custom_js":"","_kad_blocks_footer_custom_js":"","csco_singular_sidebar":"","csco_page_header_type":"","csco_page_load_nextpost":"","csco_post_video_location":[],"csco_post_video_url":"","csco_post_video_bg_start_time":0,"csco_post_video_bg_end_time":0,"footnotes":""},"categories":[5392,5316],"tags":[4163,4456,4492],"class_list":{"0":"post-23202","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-fitness-and-nutrition","8":"category-trying-to-conceive","9":"tag-fertility","10":"tag-healthy-pregnancy","11":"tag-vitamin-d","12":"cs-entry","13":"cs-video-wrap"},"acf":[],"yoast_head":"\n