Vitamin D deficiency has been proven to affect fertility in mammals, but data in human is less convincing. In particular, data on in vitro fertilization (IVF), an attractive model to draw information on this topic, are sparse and conflicting. Our objective was to investigate IVF outcome in women with deficient 25-hydroxy-vitamin D [25(OH)D] serum levels (30 ng/mL) had the highest chances of pregnancy. Vitamin D is an emerging factor influencing female fertility and IVF outcome. Additional studies are pressingly needed to confirm a causal relationship and to investigate the potential therapeutic benefits of vitamin D supplementation.

The present study was designed to investigate the relationship between pre-mating nutrition and the relative amounts of a panel of developmentally relevant genes in ovine oocytes and granulosa cells. Cast age ewes were fed a ration providing 0.5× (0.5 M) or 1.5× (1.5 M) live weight maintenance requirements for 2 weeks before slaughter. The ewes were synchronized and superovulated with FSH and pregnant mares serum gonadotropin. At slaughter, oocytes and granulosa cells were aspirated from follicles >2 mm in diameter and the relative abundance of 8 and 17 transcripts in oocytes and granulosa cells respectively were analyzed by semi-quantitative RT-PCR. In the oocytes, no differences between groups were observed for five transcripts (GDF9, BMP15, c-kit, glucose transporter 1 (SLC2A1), and hexokinase 1), but a lower amount of glucose transporter 3 (SLC2A3), sodium/glucose cotransporter 1 (SLC5A1), and Na+/K+ ATPase mRNAs was detected in the 0.5 M group. Increased expression of PTGS2, HAS2, and the leptin receptor long form was observed in granulosa cells from the 0.5 M group. No differences between groups were observed for the other transcripts (early growth response factor-1, estrogen receptor-α, LH and FSH receptors, gremlin 1, pentraxin 3, KIT ligand, glucose transporters 1, 3, and 8, IGF1, IGF1 receptor, leptin receptor, and tumor necrosis factor-stimulated gene 6). Expression of leptin and sodium/glucose cotransporter 1 was not detected in both groups. The present data indicate that pre-mating nutrition is associated with alteration in the mRNA content in oocytes and surrounding follicle cells in ewes, which may account for the reduced reproductive performance typical of ewes that are fed a restricted ration for a short period of time before mating.

Summary: Background: The association between alcohol intake and male reproductive function is still controversial. In the frame of a prospective cohort study, designed to investigate the relation between life style and fertility, we performed a cross‐sectional analysis of semen quality.Methods: Men of subfertile couples, referring to an Italian Infertility Unit and eligible for assisted reproductive techniques (ARTs), were asked about their lifestyle: BMI, smoking, caffeine intake, occupational and leisure physical activity (PA) and alcohol intake in the last year before ART procedure. Semen volume, sperm concentration, total sperm count and sperm motility were determined. Age, risk factors for impaired male fertility, caffeine, smoking, leisure PA, days of abstinence and daily calories intake were accounted for in the analyses.Results: Between September 2014 and December 2016, we enrolled 323 male patients, mean age 39.3 years. Thirty‐one (9.6%) were abstainers, 97 (30.0%) drank <1–3, 98 (30.3%) 4–7 and 97 (30.0%) ≥8 alcohol units per week. As compared to men drinking <1–3 units per week, median semen volume was higher in the 4–7 units/week group (3.0 mL, interquartile range, IQR, 2.0–4.0 vs. 2.4 mL, IQR 1.7–3.5), as well as total sperm count (87.9 mil/mL, IQR 20.2–182.1 vs. 51.5 mil/mL, IQR 15.2–114.7). Association with sperm concentration was also significant, with a U‐shaped trend in groups of alcohol intake. After adjusting for potential confounders, these relations were confirmed. Similar patterns were observed in subgroups of leisure PA and risk factors for impaired male fertility, although these estimates often lacked statistical significance, presumably because of low sample size.Conclusions: Moderate alcohol intake appears positively associated to semen quality in male partners of infertile couples undergoing ARTs.