Vitamin D levels and biomarkers of male fecundity: A study from the Danish National Birth Cohort
Andrology. 2025 May 18. doi: 10.1111/andr.70061 PDF behind paywall
Anne Gaml-Sørensen 1, Nis Brix 1 2, Sandra Søgaard Tøttenborg 3 4, Christian Lindh 5, Karin Sørig Hougaard 5 6, Siri Eldevik Håberg 7, Gunnar Toft 8, Jens Peter Ellekilde Bonde 3 4, Cecilia Høst Ramlau-Hansen 1
Background: Vitamin D is metabolised throughout the male reproductive system, suggesting a direct regulatory role of vitamin D in male reproduction.
Objectives: To investigate the association between plasma vitamin D levels at sperm ejaculation and during spermatogenesis and biomarkers of male fecundity in young men.
Materials and methods: From the Fetal Programming of Semen Quality cohort, Denmark, 2017-2019, 1047 young men provided a semen and a blood sample, and self-measured their testes volume at a clinical visit. Plasma levels of vitamin D (25(OH)D3) and reproductive hormones were measured in the blood sample. Relative percentage differences in semen characteristics, testes volume and reproductive hormone levels were analysed according to measured vitamin D levels (categorised, continuous and as restricted cubic splines) at sperm ejaculation. Additionally, we used the seasonal variation in endogenous vitamin D synthesis to estimate individual vitamin D levels 3 months prior to sperm ejaculation (at initiation of spermatogenesis) in addition to 2 and 1 month before. This was analysed following the same strategy.
Results: Compared to measured vitamin D levels >75 nmol/L, levels <25 nmol/L at sperm ejaculation were associated with lower total sperm count (‒15% [95% confidence interval: ‒33%; 8%]), and a higher proportion of non-progressive and immotile spermatozoa (11% [95% confidence interval: 0%; 24%]). Lower measured vitamin D levels were also associated with higher oestradiol, lower sex hormone-binding globulin and lower follicle-stimulating hormone, in dose-dependent manners. Vitamin D levels estimated before and during spermatogenesis yielded similar associations as vitamin D levels measured at sperm ejaculation.
Discussion: By using the seasonal variation in endogen vitamin D synthesis, we were able to estimate individual vitamin D levels during spermatogenesis.
Conclusion: Lower vitamin D levels before and during spermatogenesis and at sperm ejaculation were associated with lower total sperm count and sperm motility and an altered reproductive hormone profile.
Sperm need adequate vitamin D for 3 months that they are growing - Perplexity AI May 2025
Conclusion Spermatogenesis takes approximately 64-74 days in humans, with each cycle of the seminiferous epithelium requiring about 16 days. Evidence suggests that maintaining adequate vitamin D levels throughout this process is beneficial for optimal testicular function and sperm development. While vitamin D appears to support multiple aspects of spermatogenesis, from cell proliferation to sperm motility, clinical research in humans shows promising but sometimes inconsistent results. For men with vitamin D deficiency, supplementation may help improve testicular function and sperm parameters. However, more research is needed to establish definitive recommendations for vitamin D supplementation as a strategy to enhance male fertility.
Perplexity ful repor
Adequate levels take 2-3 months of maintenance dosing unless start with 1 week of loading doses
VitaminDWiki – Vitamin D greatly improves Fertility
- Vitamin D is needed for human fertility – goal is 50 ng – Sept 2018
- In-vitro Fertilization costs at least 10,000 dollars, Vitamin D costs 5 dollars
- Women were 50X more likely to be fertile if just 1 ng higher level of vitamin D – Nov 2024
- Infertile patients 1.7X more-likely to become pregnant if take Vitamin D – meta-analysis Feb 2023
- Live birth 1.7 X more likely after IVF if good level of vitamin D – meta-analysis Aug 2020
- If diagnosed infertile, more likely to have live birth if Vitamin D fortification – Feb 2020
- Preconception vitamin D is great - every extra 10 ng associated with 10 percent more likely to have live birth – Aug 2018
- Women with more than minimum vitamin D were 3.4 X more likely to achieve pregnancy and 1.6 X more likely to have live births – June 2017
- Assisted Reproduction – 5 studies concluded vitamin D repletion helps – Review March 2015
- Pregnancy success increased 30 percent if sunny (or vitamin D) one month earlier – June 2015
- IVF 4X more successful for white women with lots of vitamin D – many studies
Increased male Vitamin D increases fertility
- Birth rates doubled with Vitamin D - 300,000 IU for infertile men – RCT Nov 2017
- Higher vitamin D results in 22% fewer abnormal sperm (Mendelian analysis) – May 2024
- Conception was 3.7X more likely if the male had a good level of Vitamin D – July 2022
- Far better sperm in fertility clinic if more than 30 ng of Vitamin D - June 2022
- Fertility (sperm) associated with vitamin D – meta-analysis Sept 2019
- Infertility - 71 percent of the time of BOTH partners had less than 20 ng of Vitamin D – Aug 2017
- Male fertility 4 X higher if high Vitamin D – Nov 2015
- Vitamin D somewhat assists reproduction – both the mother and the father – May 2014
Decreased Fertility if decreased Vitamin D Receptor
- Unexplained infertility 4X more likely if poor vitamin D receptor – Dec 2020
- Male Infertility is associated with poor Vitamin D Receptor – July 2021