P-020 Influence of vanadium and lead in seminal fluid on assisted reproductive techniques
Authors: Rodriguez Díaz R , Blanes-Zamora R , Gomez-Rodriguez J , Alcaide Ruggiero L , Hardisson A , Gonzalez-Weller D , Gutierrez A.J , Paz S , Rubio C , Gonzalez-Davila E 
Published: June 2022

Abstract

Study question
In recent decades there has been an increase in environmental contaminants than can affect assisted reproduction techniques. We analyze the influence of vanadium (V) and lead (Pb) on these results.

Summary answer
Higher seminal fluid V levels affect fertilization rate (FR). Higher Pb and V levels decrease embryo cleavage rate (CR).

What is known already
Some animal studies have shown that V produces toxicity in the male reproductive system through oxidative stress, and this leads to decreases sperm count and motility, as well increased concentration of abnormal sperm.
Pb is one of the main pollutants and, it accumulates in the male reproductive organs, deteriorates the quality of semen, increases the frequency of spontaneous abortion and male infertility. And it has also been seen that it inhibits sperm functions in vitro, although its mechanism of action is still unknown.

Study design, size, duration
A prospective study was conducted in 102 males, with a mean age of 38.0 ± 5.7, attended successively for initial evaluation, in the Human Reproduction Unit of the Hospital Universitario de Canarias, between february and april 2018, who underwent a semen analysis and metal detection and, subsequently, an IVF/ICSI treatment during years 2019 and 2020 (n = 92). The relationship between the presence of metals and the results of ART has been established.

Participants/materials, setting, methods
We included two groups based on semen parameters: 41 patients with pathological spermiograms (40.2%), while the remaining 61 (59.8%) had a normal semen analysis and constituted the control group.The study of seminal parameters was performed according to the WHO guidelines. The metals analysis was carried out in the Toxicology Area of the Universidad de La Laguna, using the digestion for microwave method. Metal measurement was performed using inductively coupled plasma optical emission spectrometry (ICP-OES).

Main results and the role of chance
In our study we have observed 79.4% of patients have V in semen. Significant differences have been found in the concentration of V in semen (t100=1.988, p = 0.05), is higher in patients who drink alcohol (0.51± 0.40 mg/Kg) than in abstinent patients (0.35± 0.30 mg/Kg).
The group with FR above 75% presented lower V values compared to those with rates below 75% (p = 0.039). Within this last group, 33.3% present V values higher than 0.7 mg / kg compared to 15.8% who present it in the group with FR greater than 75% (OR = 2.67 CI95% 1.01, 7.52; p = 0.048).
A statistical relationship was found between CR and Pb and V. Those who did not reach 100% CR presented higher Pb values (p = 0.052). Of them, 63.6% presented Pb compared to 38.5% in the group reaching 100% division. This same relationship was observed for V, with higher values in the group that did not reach 100% (p = 0.032), and V being present in 90.9% of the samples compared to 79.5% in the group reaching 100%.

Limitations, reasons for caution
The limitation of this study was the volume of semen that could be obtained for the metal detection, only 0.5 ml. This was because the semen sample was used at the same time to make a diagnosis of infertility though a spermiogram

Wider implications of the findings
The determination of metals in semen opens a new field in the study of infertility, and many cases of unknown infertility could due to metal presence or absence in seminal fluid, with the option of performing several treatments to correct these possible anomalies.

Trial registration number
not applicable