Low-serum antimüllerian hormone is linked with poor semen quality in infertile men screened for participation in a randomized controlled trial.

OBJECTIVE: To investigate possible associations between serum antimüllerian hormone (AMH) concentration and semen quality in infertile men. Studies investigating the associations between serum AMH concentration and semen quality in infertile men have shown conflicting results. DESIGN: Infertile men were included during screening for participation in the First in Treating Male Infertility Study, a double-blinded, placebo-controlled, 1:1, single-center randomized controlled trial. SETTING: Not applicable. PATIENTS: At the screening visit, 400 participants produced a semen sample and had their serum analyzed for AMH concentration. INTERVENTION: Not applicable. MAIN OUTCOME MEASURES: Serum AMH concentration and semen quality. RESULTS: All men were stratified according to serum AMH concentrations in quartiles (Q1-Q4). Men in the lowest quartile had a lower sperm concentration (1 × 106/mL) (Q1: 8.0 vs. Q2: 10.4 vs. Q3: 11.0 vs. Q4: 13.0), total sperm count (1 × 106) (Q1: 29.1 vs. Q2: 38.2 vs. Q3: 44.4 vs. Q4: 55.7), sperm motility (%) (Q1: 41 vs. Q2: 57 vs. Q3: 50 vs. Q4: 53), and progressive sperm motility (%) (Q1: 31 vs. Q2: 44 vs. Q3: 35 vs. Q4: 40) compared with the other quartiles. Moreover, men with a sperm concentration <2 million/mL had a lower serum AMH concentration compared with men having 2-16 × 106 /mL and >16 × 106/mL (31 pmol/L vs. 38 pmol/L vs. 43 pmol/L, respectively). In accordance, men with sperm motility <20% had a lower serum AMH concentration compared with men with sperm motility 20%-42%, and >42% (31 pmol/L vs. 43 pmol/L. vs. 39 pmol/L, respectively). CONCLUSION: This study shows that low serum AMH concentration is associated with poor semen quality in infertile men, which implies that serum AMH concentration may have clinical value during the evaluation of male infertility. CLINICAL TRIAL REGISTRATION NUMBER: NCT05212337.

High-dose vitamin D3 supplementation shows no beneficial effects on white blood cell counts, acute phase reactants, or frequency of respiratory infections.

BACKGROUND: Vitamin D has been suggested to influence the immune system, and vitamin D metabolites and the vitamin D receptor (VDR) are generated and expressed in white blood cells (WBC). Moreover, vitamin D status has been associated with incidence and prognosis of some respiratory tract infections (RTI). Therefore, we investigated the effect of vitamin D3 supplementation on WBC, acute phase reactants (APR), and the risk of developing RTIs. METHODS: A double-blinded, randomized, placebo-controlled clinical trial of 307 infertile men with multiple secondary immunological endpoints. The vitamin D3 group (n = 151) initially received 300,000 IU (7,500 µg) cholecalciferol once - followed by 1,400 IU (35 µg) daily for 150 days. The placebo group (n = 156) did not receive active ingredients. RESULTS: At baseline, stratification into clinically relevant groups of vitamin D status (< 25; 25-50; 50-75; >75 nmol/L), showed an inverse association with total leucocyte concentrations (7.0 vs. 6.0 vs. 6.0 vs. 5.5 (109/L); p = 0.007), lymphocytes (2.4 vs. 2.1 vs. 2.0 vs. 2.0 (109/L); p = 0.048), CRP (2.0 vs. 1.7 vs. 1.2 vs. 1.2 (mg/L); p = 0.037), and orosomucoid (0.82 vs. 0.77 vs. 0.76 vs. 0.70 (g/L); p = 0.015). After 150 days, no differences were detected in WBC counts or APRs between the vitamin D3 and the placebo group. However, vitamin D3 treated men had a higher prevalence of self-reported RTIs compared with the placebo group (55% vs. 39%; p = 0.005). CONCLUSIONS: High-dose vitamin D3 supplementation did not alter WBCs or APRs, but a higher prevalence of respiratory infections was observed in the vitamin D3 group. Serum 25(OH)D3 was negatively correlated with most WBCs, indicating that vitamin D status may be linked with inflammation and WBC turnover, but not an important determinant of developing RTIs. TRIAL REGISTRATION: NCT01304927 (ClinicalTrials.gov). Registered February 20, 2011.

High-dose cholecalciferol supplementation to obese infertile men is sufficient to reach adequate vitamin D status.

Obesity is associated with low vitamin D status, and the optimal supplement and dosage of cholecalciferol (vitamin D3) or calcidiol (25OHD) for individuals with obesity have been debated. We aimed to determine the effect of high-dose vitamin D3 supplementation on achieving adequate vitamin D levels among infertile men with normal weight v. obesity. Here, we present secondary end points from a single-centre, double-blinded, randomised clinical trial, comprising 307 infertile men randomised to active or placebo treatment for 150 days. Men in the active group initially received an oral bolus of 300 000 mg of vitamin D3, followed by daily supplementation with 1400 mg of vitamin D3 and 500 mg of calcium. Baseline BMI was listed as a predefined subgroup. At baseline, serum 25OHD was significantly higher in men with normal weight (BMI < 25 kg/m2) compared with men with overweight (BMI 25-30 kg/m2) and obesity (BMI > 30 kg/m2) (48 nmol/l v. 45 nmol/l and 39 nmol/l, respectively; P = 0·024). After the intervention, men with normal weight, overweight and obesity treated with vitamin D3 had a significantly higher serum 25OHD compared with corresponding placebo-treated men (BMI < 25 kg/m2: 92 nmol/l v. 53 nmol/l, BMI = 25-30 kg/m2: 87 nmol/l v. 49 nmol/l and BMI > 30 kg/m2: 85 nmol/l v. 48 nmol/l; P < 0·001 for all, respectively). In conclusion, we show that high-dose vitamin D3 supplementation to infertile men with obesity and low vitamin D status is sufficient to achieve adequate serum 25OHD levels.

Calcium and vitamin D homoeostasis in male fertility.

Calcium and vitamin D have well-established roles in maintaining calcium balance and bone health. Decades of research in human subjects and animals have revealed that calcium and vitamin D also have effects on many other organs including male reproductive organs. The presence of calcium-sensing receptor, vitamin D receptor, vitamin D activating and inactivating enzymes and calcium channels in the testes, male reproductive tract and human spermatozoa suggests that vitamin D and calcium may modify male reproductive function. Functional animal models have shown that vitamin D deficiency in male rodents leads to a decrease in successful mating and fewer pregnancies, often caused by impaired sperm motility and poor sperm morphology. Human studies have to a lesser extent validated these findings; however, newer studies suggest a positive effect of vitamin D supplementation on semen quality in cases with vitamin D deficiency, which highlights the need for initiatives to prevent vitamin D deficiency. Calcium channels in male reproductive organs and spermatozoa contribute to the regulation of sperm motility and capacitation, both essential for successful fertilisation, which supports a need to avoid calcium deficiency. Studies have demonstrated that vitamin D, as a regulator of calcium homoeostasis, influences calcium influx in the testis and spermatozoa. Emerging evidence suggests a potential link between vitamin D deficiency and male infertility, although further investigation is needed to establish a definitive causal relationship. Understanding the interplay between vitamin D, calcium and male reproductive health may open new avenues for improving fertility outcomes in men.