Journal of Clinical Medicine Article Obesity Surgery Improves Hypogonadism and Sexual Function in Men without Effects in Sperm Quality Inka Miñambres 1,2,3,† , Helena Sardà 1,2,† , Eulalia Urgell 4 , Idoia Genua 1,2 , Analía Ramos 5 , Sonia Fernández-Ananin 6 , Carmen Balagué 6 , Jose Luis Sánchez-Quesada 7,8 , Lluís Bassas 9, * and Antonio Pérez 1,2,3, * 1 Endocrinology and Nutrition Department, Hospital de la Santa Creu i Sant Pau, 08041 Barcelona, Spain 2 Medicine Department, Universitat Autònoma de Barcelona (UAB), 08193 Barcelona, Spain 3 CIBER of Diabetes and Metabolic Diseases (CIBERDEM), 08041 Barcelona, Spain 4 Biochemistry Department, Hospital de la Santa Creu i Sant Pau, 08041 Barcelona, Spain 5 Endocrinology and Nutrition Department, Hospital Germans Trias i Pujol, 08916 Badalona, Spain 6 General Surgery Department, Hospital de la Santa Creu i Sant Pau, 08041 Barcelona, Spain 7 Cardiovascular Biochemistry Group, Research Institute of the Hospital de la Santa Creu i Sant Pau (IIB Sant Pau), 08041 Barcelona, Spain 8 Molecular Biology and Biochemistry Department, Faculty of Medicine, Universitat Autònoma de Barcelona (UAB), 08193 Barcelona, Spain 9 Andrology Department, Fundació Puigvert, 08025 Barcelona, Spain * Correspondence: lbassas@fundacio-puigvert.es (L.B.); aperez@santpau.cat (A.P.); Tel.: +34-935565661 (A.P.) † The authors contributed equally to this work. Abstract: (1) Background: Obesity is associated with hypogonadism, sexual dysfunction, and im- paired fertility in men. However, its effects on semen parameters or sexual function remain debatable. (2) Methods: This paper involves a longitudinal study in men submitted for obesity surgery at a Citation: Miñambres, I.; Sardà, H.; university tertiary hospital. Patients were studied at baseline and at 6, 12, and 18 months after obesity Urgell, E.; Genua, I.; Ramos, A.; Fernández-Ananin, S.; Balagué, C.; surgery. At each visit, anthropometry measures were collected and hormonal and semen parameters Sánchez-Quesada, J.L.; Bassas, L.; were studied. Sexual function was evaluated with the International Index of Erectile Function (IIEF). Pérez, A. Obesity Surgery Improves (3) Results: A total of 12 patients were included. The average body mass index of patients decreased Hypogonadism and Sexual Function from 42.37 ± 4.44 to 29.6 ± 3.77 kg/m2 at 18 months after surgery (p < 0.05). Hormonal parameters in Men without Effects in Sperm improved after obesity surgery. The proportion of sperm cells with normal morphology tended Quality. J. Clin. Med. 2022, 11, 5126. to decrease from baseline and became most significant at 18 months (5.83 ± 4.50 vs. 2.82 ± 2.08). https://doi.org/10.3390/ No significant changes were found in the remaining semen parameters. Erectile function improved jcm11175126 significantly at six months after surgery. (4) Conclusions: The authors believe that, in general, the Academic Editor: Marijana Tadic effects of obesity surgery on fertility may be limited or even deleterious (at least in the short and midterm follow-up). Received: 11 July 2022 Accepted: 27 August 2022 Keywords: hypogonadism; obesity; obesity surgery; sperm; fertility Published: 31 August 2022 Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affil- 1. Introduction iations. Obesity is an increasingly prevalent worldwide disease which is reaching epidemic proportions [1] and confers an increased mortality due to its related complications, such as multiple metabolic and cardiovascular disorders [2]. It is also linked to other health Copyright: © 2022 by the authors. concerns including reproductive health [3]. Licensee MDPI, Basel, Switzerland. Hypogonadism is more prevalent in men with obesity and metabolic syndrome, since This article is an open access article testosterone levels appear to be inversely related to body mass index (BMI) and with the distributed under the terms and presence of obesity-associated comorbid conditions such as type 2 diabetes, obstructive conditions of the Creative Commons sleep apnea, and metabolic syndrome [4–7]. Data from the European male ageing study Attribution (CC BY) license (https:// (EMAS) have shown that increased BMI was associated with decreased total and free creativecommons.org/licenses/by/ testosterone concentrations and with normal or decreased concentrations of luteinizing 4.0/). hormone (LH) [8]. This has suggested the presence of a partial functional hypogonadotropic J. Clin. Med. 2022, 11, 5126. https://doi.org/10.3390/jcm11175126 https://www.mdpi.com/journal/jcm J. Clin. Med. 2022, 11, 5126 2 of 9 hypogonadism, the so-called ‘male obesity-related secondary hypogonadism’ (MOSH) [8,9]. The altered hormonal regulation seen in obesity seems to present along with a greater degree of sexual disfunction when compared with normal weight controls [10]. Additionally, obesity has been linked with a decrease of sperm quality and, therefore, male fertility [11,12]. Although the proposed causal pathophysiological mechanisms involved in this are not well understood, underlying oxidative stress and inflammation may be important implicated mechanisms [13]. Lifestyle modifications that lead to weight loss have been determined to improve most obesity-related metabolic comorbidities and to increase total and free testosterone concentrations in men [14–17]. Bariatric surgery is currently the most effective treatment for morbid obesity, resulting in a significant and permanent weight loss. Concerning gonadal function, surgery has been described to achieve an 87% resolution of the male obesity-related secondary hypogonadism [3]. However, the effects of obesity surgery on semen parameters or sexual function remain debatable. The aim of the present study was to analyze the effects of bariatric surgery on hormonal and semen parameters and sexual function in men with severe obesity. 2. Materials and Methods This was a longitudinal study performed at a university tertiary hospital in Spain. The study included twelve men who met the National Institute of Health criteria for obesity surgery and were already scheduled for surgical procedures. All subjects gave written informed consent to participate in the present study. The protocol was approved by the clinical research ethics committee of the Hospital de la Santa Creu i Sant Pau. All procedures performed involving human participants were in accordance with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. We excluded patients above 55 years old and patients with kidney, liver, gonadal, or pituitary disease or concomitant treatments that could disturb/interfere with sexual hormone concentrations or semen parameters. All patients included were studied before (baseline) and at 6, 12, and 18 months after bariatric surgery. Anthropometry parameters (weight, height, and BMI) and the presence of comorbidities associated with obesity were recorded before surgery and during follow-up. Dyslipidemia was defined as the presence of any of the following: triglyceride concentrations ≥ 1.7 mmol/L, HDLc concentrations < 1 mmol/L, LDLc concentrations > 4.14 mmol/L, or hypolipidemic treatment. The presence of metabolic associated fatty liver disease (MAFLD) was assessed by means of a baseline abdominal echography and by the NAFLD fibrosis score at baseline and follow-up [18]. The percentage of total weight loss (%TWL) was defined as the preoperative weight minus the follow-up weight, divided by the preoperative weight and multiplied by 100 [19]. Hormonal parameters measured included total testosterone, sex hormone binding globulin (SHBG), estradiol, prolactin, luteinizing hormone (LH), and follicle-stimulating hormone (FSH). Total testosterone and prolactin were determined using the electrochemi- luminescence immunoassay (Cobas E601 analyzer; Roche Diagnostics GmbH, Mannheim, Germany). Assessment of FSH, LH, and estradiol was performed with the chemilumi- nescent microparticle immunoassay (CMIA) (Architect; Abbott Laboratories, Chicago, IL, USA), and SHBG was measured using the chemiluminescent enzyme immunoassay (Immulite 1000; Siemens Healthcare Diagnostics, Llanberis, UK). We calculated free testos- terone by Vermeulen’s equation [20]. We defined hypogonadism as a total testosterone value < 9.2 nmol/L [21]. Semen samples were collected at each study visit on the premises of the hospital by masturbation in a clean, non-toxic container. These samples were immediately delivered to the laboratory. A sexual abstinence of three to five days was required. After liquefaction at 37 ◦ C (98.6 ◦ F) under gentle mixing, semen analysis was performed according to methods and reference limits of the WHO [22,23]. Semen volume was measured by recording the net weight of the container, assuming a density of 1 g/mL. pH was assessed with J. Clin. Med. 2022, 11, 5126 3 of 9 colorimetric strips; sperm concentration was performed on diluted, immobilized samples using hemocytometer chambers; motility was analyzed at room temperature; and sperm morphology of fixed smears stained with Diff-Quik was carried out following WHO criteria, including calculation of teratozoospermia index (TZI) [22]. Sperm DNA fragmentation was analyzed with the sperm chromatin dispersion test (SCD) [24]. Anti-sperm antibodies were identified with the mixed antiglobulin reaction (MAR) test (SpermMar IgG, Fertipro, Beermen, Belgium). The World Health Organization’s reference values for human semen characteristics were used when needed [23]. Sexual function was evaluated with the International Index of Erectile Function (IIEF). The questionnaire includes five main domains of male sexual function: erectile function, orgasmic function, sexual desire, intercourse satisfaction, and overall satisfaction. A score of 0/1–5 is awarded to each of the 15 questions of the test. Higher scores indicate more conserved sexual function. The total possible score for the erectile function domain ranges from 1 to 30, and erectile dysfunction is classified into four categories based on the scores: severe (6–10), moderate (11–16), mild (17–25), and no erectile dysfunction (26–30) [25]. A minimum sample size was calculated considering clinically significant changes in sperm and testosterone concentrations. In both cases, an alfa error = 0.05 and beta = 0.20 were considered. By assuming a clinically relevant mean difference in sperm concentrations of 15 million/mL (pre- and post-surgery) and a standard deviation of 15 million/mL, the resulting sample size was eight patients. When considering an expected change in total testosterone concentrations of 2.5 nmol/L with a 2 nmol/L standard deviation, the resulting sample size was six patients. The statistical analyses were made with the SPSS 26.0 program. Variables were expressed as means ± standard deviation (SD) for continuous variables and absolute numbers with percentages for categorical variables. We used non-parametric tests (i.e., the Wilcoxon and McNemar tests) to analyze the continuous and categorical variables during follow-up, respectively. Correlations between changes observed were performed by means of Spearman correlation analysis. 3. Results A total of 12 male patients completed the follow-up. Baseline and final clinical charac- teristics are shown in Table 1. Seven patients (58.3%) underwent gastric bypass and five (41.7%) underwent sleeve gastrectomy. The evolution of BMI and the percentage of total weight lost (%TWL) during the follow-up are shown in Figure 1. Table 1. Baseline and follow-up clinical and metabolic variables. Baseline (n = 12) 18 Months (n = 11) Age (years) 45 ± 4.87 46.17 ± 4.86 BMI (kg/m2 ) 42.37 ± 4.44 29.6 ± 3.77 * Diabetes mellitus, n (%) 3 (25) 2 (18.2) Hypertension, n (%) 5 (41.7) 2 (18.2) Dyslipidemia, n (%) 10 (83.3) 1 (9.1) * OSA, n (%) 6 (50) 3 (27.3) Hepatic steatosis † (%) 11 (9.7) - NAFLD fibrosis score −1.34 ± 1.01 −1.69 ± 0.94 Fasting glycemia (mmol/L) 6.18 ± 1.47 5.71 ± 2.27 HbA1c (%) 5.75 ± 0.62 5.45 ± 0.97 * Triglycerides (mmol/L) 3.66 ± 1.36 0.98 ± 0.41 * Total cholesterol (mmol/L) 4.86 ± 0.91 4.44 ± 0.96 * LDLc (mmol/L) 3.08 ± 0.77 2.63 ± 0.72 * HDLc (mmol/L) 1.06 ± 0.16 1.36 ± 0.27 * BMI, body mass index; OSA, obstructive sleep apnea. † Assessed by abdominal echography. Data are expressed as mean ± SD or n (%). * p < 0.05. Triglycerides (mmol/L) 3.66 ± 1.36 0.98 ± 0.41 * Total cholesterol (mmol/L) 4.86 ± 0.91 4.44 ± 0.96 * LDLc (mmol/L) 3.08 ± 0.77 2.63 ± 0.72 * HDLc (mmol/L) 1.06 ± 0.16 1.36 ± 0.27 * J. Clin. Med. 2022, 11, 5126 BMI, body mass index; OSA, obstructive sleep apnea. † Assessed by abdominal echography. Data4 of 9 are expressed as mean ± SD or n (%). * p < 0.05. Figure 1. Evolution of BMI and %TWL during follow-up. Figure 1. Evolution of BMI and %TWL during follow-up. The hormone profile evolution during follow-up is shown in Table 2. Hypogo- The hormone nadism profilein was present evolution during(33.3%) four patients follow-up is shownand at baseline in Table 2. Hypogonadism resolved after surgery in was present in four patients (33.3%) at baseline and resolved after surgery in all cases. all cases. Total and free testosterone in patients with and without hypogonadism were 7.72 ± 1.53 vs. 13.89 ± Total and free testosterone in patients with and without hypogonadism were 7.72 ± 1.53 vs. 4.86 nmol/L (p = 0.036) for total testosterone and 0.22 ± 0.04 0.31 ±± 0.05 vs. 13.89 nmol/L(p(p= =0.036) 4.86 nmol/L 0.009) forfor free total testosterone, testosterone andrespectively. 0.22 ± 0.04 vs. The 0.31increase observed ± 0.05 nmol/L in these hormonal concentrations and in SHGB after bariatric (p = 0.009) for free testosterone, respectively. The increase observed in these hormonal surgery, according to the presence or absence of hypogonadism, was similar (data not concentrations and in SHGB after bariatric surgery, according to the presence or absence shown). There was a signifi- cant positive correlation of hypogonadism, was similar between(datathenot increase shown).in total testosterone There and the percentage was a significant positive of total weight lost at 18 months (rs 0.782; p correlation between the increase in total testosterone and the percentage of total weightwas = 0.004). Changes in SHBG at 18 months also correlated with the percentage of total weight lost (rs 0.718; p = 0.013) and marginally lost at 18 months (rs 0.782; p = 0.004). Changes in SHBG at 18 months was also correlated correlated with changes in NAFLD fibrosis score (rs −0.6; p = 0.051). with the percentage of total weight lost (rs 0.718; p = 0.013) and marginally correlated with changes Table in NAFLD fibrosis 2. Hormone score (rsprofile and seminogram −0.6; pat=baseline 0.051). and during follow-up. Regarding semen parameters, there was a trend towards a decrease in the percentage Hormone Variables of sperm cells Before with(n =normal Surgery 12) morphology 6 Months (n = 11) after bariatric 12 Months surgery (n = 12) (reaching statistical 18 Months (n = 11) Total testosterone (nmol/L) significance 11.83 at 18±months) 4.99 and an21.19 increase ± 5.97 in ** the number 20.77of±sperm 6.61 ** with multiple 22.91 ±defects 4.88 ** Free testosterone (nmol/L) (12 months).0.28 No± significant 0.06 changes 0.42 ±were 0.10 **found in the rest 0.41 of *semen parameters ± 0.15 0.41 ± 0.05after ** SHBG (nmol/L) 22.54 ± 12.10 39.13 ± 10.82 ** 41.49 ± 12.55 ** 41.30 ± 14.41 ** Estradiol (nmol/L) bariatric surgery (Table 2). The 0.11 0.11 ± 0.36 proportion ± 0.38 of patients with one or more0.10 0.11 ± 0.02 abnormal ± 0.05 Prolactin (mUI/L) parameters223.00 was ± not reduced after 142.3 the ± 142.972 surgery. 85.14 The increase 212.196 ±in the percentage 156.09 213.22of± sperm 184.33 LH (UI/L) with multiple abnormalities 2.91 ± 1.47 seen at2.96 12±months 0.97 correlated2.93 with %TWL (rs 0.886; ± 1.41 p =± 0.019). 3.41 1.23 MOSH (N (%)) 4 (33.3%) 0 (0) * 0 (0) * 0 (0) * FSH (UI/L) None of the patients 4.28 ± 1.5 showed the presence 4.37 ± 1.7of anti-sperm 4.53 antibodies ± 1.00 throughout the 5.32 study. ± 1.68 * Semen parameters Before Surgery (n = 12) 6 Months (n = 11) 12 Months (n = 12) 18 Months (n = 11) Table 2. Hormone and seminogram profile at baseline and during follow-up. Semen volume (mL) 2.9 ± 1.75 2.59 ± 0.81 3.13 ± 1.85 3.16 ± 1.48 Semen pH Before 7.63Surgery ± 0.25 (n = 7.66 ± 0.29 7.56 ± 0.18 7.57 ± 0.10 Hormone Sperm Variables concentration (×106 /mL) 48.75 ± 34.43 6 Months (n = 11) 40.21 ± 31.41 12 Months 39.43 ± (n = 12) 29.26 18 Months 44.85 (n = 11) ± 43.6 Total sperm count (×106 ) 118.95 ± 12) 79.91 110.12 ± 102.37 106.35 ± 105.46 157.08 ± 206.28 TotalLeucocyte testosterone (nmol/L) concentration (×106 /mL) 11.83  4.99 0.17 ± 0.39 21.19 0.00 ± 5.97 0.00 ** 20.77 ± 0.00 6.61 0.00** 22.910.31  4.88 ** ± 0.62 Free testosterone (nmol/L) Sperm progressive motility (%) 0.28  0.06 38.66 ± 17.68 0.42  0.10 ** 33.9 ± 20.62 0.41  0.15 * 31.12 ± 12.79 0.41  0.05 ** 26 ± 14.71 Sperm with normal morphology (%) 5.83 ± 4.50 5.55 ± 4.54 3.14 ± 1.67 2.82 ± 2.08 * SHBG (nmol/L) Sperms with multiple defects (%) 22.54 12.10 43.83 ±9.90 39.13 45.55±10.82 8.65 ** 41.49  12.55 49.57 ± 8.16 ** * 41.30 46.55  14.41 ** ± 8.26 Estradiol (nmol/L) Index (%) Teratozoospermia 0.11±0.12 1.55 0.36 0.11 1.57 ± 0.38  0.11 0.11 1.60±0.02 0.11 0.101.57  0.05 ± 0.10 Sperm DNA fragmentation (%) 25.27 ± 9.23 29.56 ± 13.48 34.43 ± 11.04 34.22 ± 13.89 Prolactin (mUI/L) Degraded sperm (%) 223.00  142.3 3.18 ± 3.74 142.972 85.14 1.67 ± 0.87 212.196 2.57±156.09 0.79 213.224.22  184.33 ± 5.36 LH (UI/L) Patients with one or more abnormal 2.91 9 (75) 1.47  2.96  0.97 6 (54.5) 2.937 (58.3) 1.41 3.41 9 (81.8) 1.23 semen parameters † (N (%)) † Includes volume, sperm concentration, progressive motility, normal morphology, Values are expressed as mean + SD or N(%). * p < 0.05 compared to pre-surgery values. ** p < 0.01 compared to pre-surgical values. Regarding semen parameters, there was a trend towards a decrease in the percent- age of sperm cells with normal morphology after bariatric surgery (reaching statistical significance at 18 months) and an increase in the number of sperm with multiple defects (12 months). No significant changes were found in the rest of semen parameters after J. Clin. Med. 2022, 11, 5126 5 of 9 bariatric surgery (Table 2). The proportion of patients with one or more abnormal param- eters was not reduced after the surgery. The increase in the percentage of sperm with multiple abnormalities seen at 12 months correlated with %TWL (rs 0.886; p = 0.019). None of the patients showed the presence of anti-sperm antibodies throughout the study. Concerning sexual function, erectile function assessed by means of the IIEF test im- proved significantly at six months after surgery. All scores from the IIEF test are shown in Table 3. Table 3. Sexual function parameters. Erectile Function Variables Before Surgery (n = 12) 6 Months (n = 11) 12 Months (n = 12) 18 Months (n = 11) Erectile function 23.08 ± 7.57 27.18 ± 6.19 * 26.82 ± 4.21 27 ± 4.26 Orgasmic function 9.25 ± 3.67 11.18 ± 3.06 11.18 ± 4.14 11.60 ± 2.011 Sexual desire 9.55 ± 1.036 9.18 ± 1.94 9.36 ± 1.28 9.90 ± 0.316 Intercourse satisfaction 6.75 ± 1.76 6.73 ± 1.27 6.36 ± 1.80 6.90 ± 1.96 Overall satisfaction 6.17 ± 2.08 7.64 ± 2.06 7.73 ± 2.53 7.70 ± 2.45 Values are expressed as mean + SD. * p < 0.05 compared to pre-surgery. 4. Discussion Our study confirms that weight loss attained after bariatric surgery increases total testosterone, free testosterone, and SHBG, resulting in the complete resolution of MOSH in severe obese men. The results demonstrate improved sexual function without an impact on sperm concentration and motility and an overall decline of morphology over time. Our study shows that 33.3% of male patients with severe obesity submitted to bariatric surgery had presurgical testosterone concentrations in the range of hypogonadism (<9.2 nmol/L) [21]. After surgery, they all recovered from hypogonadism and the whole group experienced a significant increase in total and free testosterone and FSH concen- trations, which indicates an improvement of the hormonal pattern characteristic of the obesity-related secondary hypogonadism (MOSH). Etiology of MOSH may be multifacto- rial and includes not only the diminished SHBG concentrations seen in obesity but also an increased aromatase activity, as well as the production of adipocytokines and gut derived endotoxins that impair kisspeptin signaling in the hypothalamus (and, consequently, GnRH secretion) [9,26]. In this respect, in our study we found increased SHBG concentrations as well as increased free testosterone concentrations after bariatric surgery, which highlights the fact that not all changes observed in testosterone concentrations are driven by the effects of obesity and weight loss on SHBG concentrations. Our findings are in agreement with the data of previous studies analyzing the effects of bariatric surgery on testosterone concentrations in men [3,27]. Previous studies investigating the effects of diet showed how an increase in total and free testosterone concentrations is correlated with the extent of weight loss. A metanalysis found that a diet-induced weight loss of 9.8% was associated with a significant increase in total testosterone of 2.8 nmol/L. Another metanalysis, which included a total of 567 patients, found that each 5 kg of weight reduction increased testos- terone by 1 nmol/L [16,17]. In our study, although the small number of patients included may hinder the achievement of significant associations, we also found a correlation between weight loss and the improvement in testosterone concentrations. Therefore, weight loss can be described as the mainstay of MOSH treatment and bariatric surgery as the most effective way of achieving its resolution. Sexual function was assessed in our study by means of the IIEF questionnaire, which estimates erectile function, orgasmic function, sexual desire, intercourse satisfaction, and overall satisfaction [25]. Our results show that bariatric surgery improved erectile function with no relevant effects on the other domains of sexual functionality. The effects of bariatric surgery on erectile function have been much less studied that the effects on hormonal concentrations, but our data are consistent with the few previous studies published that confirm a positive effect of bariatric surgery on IIEF-5 [28]. Despite the improvement in testosterone concentrations and sexual function, we did not observe a parallel improvement in sperm quality at any time point studied. In J. Clin. Med. 2022, 11, 5126 6 of 9 fact, the number of morphologically normal sperm was found to decrease after bariatric surgery, which corresponded with the increase found in the number of sperm with multiple abnormalities. This finding is intriguing, considering the significant improvement in the hormonal milieu of the obesity secondary hypogonadism. Previous studies analyzing the effects of massive weight loss with bariatric surgery are scarce. Initially, small case series pointed towards a deleterious effect of obesity surgery on fertility in men [29–31]. These anecdotic cases have been followed by a few contradictory prospective studies including small numbers of subjects. El Bardisi et al. [32] investigated the effects of sleeve gastrectomy on semen parameters at 12 months after surgery and found that men with previous oligo- and azoospermia increased their sperm concentrations. Samavat et al. [33] also found an improvement in seminal volume and viability at six months after surgery. However, these encouraging results have not been confirmed thereafter. Legro et al. [34] and Reis et al. [35] did not find any change in sperm parameters at 12 and 24 months after surgery, respectively, whereas three recent studies have reported a decrease in sperm concentration and total sperm count [36,37] and sperm volume [38]. Carette et al. [36] also found a decrease in the number of morphological normal sperm 12 months after obesity surgery. A recent meta- analysis summarizes the available literature concerning the effects of bariatric surgery in semen characteristics and concludes that this has no effect on sperm volume, concentration, total count, morphology, motility, or viability [39]. Conversely, information concerning the effect of weight loss through lifestyle modifications on sperm parameters is scarce but seems to show an improvement in some parameters of seminal quality such as sperm concentration, sperm count, or sperm morphology [40–42]. However, this information should be interpreted with caution due to the small number of studies available and the fact that there is a lack of head-to-head comparisons between lifestyle interventions and obesity surgery. In our study, we did not find any effect of bariatric surgery at any time studied on total sperm count or sperm concentrations. However, our findings which show a decrease in the percentage of normal sperm, together with an increase in the number of sperms with multiple abnormalities after obesity surgery, may indicate that obesity surgery can impair male fertility (at least during a period of weight loss). It is important to note, however, that the patients included in the present study (as well as in most previous studies) had normal seminal parameters on average, and that the small sample size of the present study as well as of previous studies limits drawing strong conclusions. This fact may have hindered the finding of potential changes in seminal quality and warrants future studies in males with obesity and seminal impairment at baseline. As a complement of basic sperm analysis, we analyzed DNA fragmentation in our study, finding an increase in DNA fragmentation during follow-up that did not reach statistical significance. Only three previous studies have analyzed DNA fragmentation, finding either no changes [33,37] or a decrease in this index [36]. While the factors that mediate the changes observed in gonadal hormones may involve the reversal of the previously commented mechanisms involved in the pathogenesis of MOSH, the factors leading the observed changes in semen parameters are less clear. Possible explanations for a worsening of semen characteristics after obesity surgery may be the decreased absorption of nutrients, the presence of nutritional deficiencies, and the possible release of toxins from adipose tissue [43,44]. It should be noted that patients submitted to obesity surgery at our institution are prescribed daily multivitamins and are examined for vitamin D, iron, B12 and folate deficiencies at six-month intervals. Other micronutrients such as copper, selenium, etc. are not routinely screened unless there is clinical suspicion of their deficiency. Concerning sexual dysfunction, the underlying mechanisms involved may be multifactorial and may include the hypogonadism itself and the association with the metabolic syndrome, which is known to lead to endothelial and erectile dysfunction [45]. Therefore, the mechanisms that explain the improvement in sexual function are closely related to an improvement in the hormonal and metabolic milieu after weight loss. The limitations of our study include its observational nature, the number of patients included in the analysis, and the lack of more than one semen sample at each time in J. Clin. Med. 2022, 11, 5126 7 of 9 each patient. Recruitment of patients willing to repeatedly provide semen samples is often difficult, especially if serial samples are required during follow-up and if stringent recruitment criteria are applied. Unlike previous studies, sample size calculation was performed in order to assure enough power to detect clinically significant changes in the main semen parameters. However, as two different bariatric procedures were performed, this sample size did not provide sufficient power to detect if each technique may have differential effects. The main strength of this study is the collection of data throughout the phase of acute weight loss and until 18 months after surgery (when weight often stabilizes). This provides important information concerning the possible influence of active or stabilized weight loss on the parameters studied. Furthermore, we carefully selected patients to exclude any confounders that could affect gonadal function. In conclusion, while weight loss through obesity surgery improves testosterone defi- ciency and sexual performance in obese men, its effects on fertility may be limited or even deleterious (at least in the short and midterm). Therefore, the presence of altered fertility in a patient with severe obesity should not be regarded as a trigger for obesity surgery. Further large-scale studies are needed to consolidate the findings provided by the present study and to explore the etiologies of impaired semen parameters in men with obesity. Author Contributions: Conceptualization, I.M., A.P. and L.B.; methodology, E.U., J.L.S.-Q. and I.M.; validation I.M., A.P. and L.B.; formal analysis, I.M. and I.G., investigation H.S., I.G., A.R., S.F.-A. and C.B.; resources I.M., A.R., S.F.-A., C.B., E.U. and J.L.S.-Q.; data curation, H.S., I.G. and I.M.; writing—original draft preparation, H.S., I.G. and I.M.; writing—review and editing, I.M., H.S., L.B. and A.P.; visualization H.S. and I.M.; supervision, I.M., L.B. and A.P.; project administration I.M. and A.P.; funding acquisition, I.M., A.P. and J.L.S.-Q. All authors have read and agreed to the published version of the manuscript. Funding: This research was partially funded by Instituto de Salud Carlos III, grant number FIS PI20-00334. Institutional Review Board Statement: The study was conducted in accordance with the Declaration of Helsinki, and approved by the Ethics Committee of Hospital de la Santa Creu i Sant Pau (protocol code IIBSP-GON-2013-74 June 2013). Informed Consent Statement: Informed consent was obtained from all subjects involved in the study. Data Availability Statement: Raw data were generated at Hospital de la Santa Creu i Sant Pau. Derived data supporting the findings of this study are available from the corresponding author (Antonio Pérez) on request. Conflicts of Interest: The authors declare no conflict of interest. References 1. Chooi, Y.C.; Ding, C.; Magkos, F. The Epidemiology of Obesity. Metabolism 2019, 92, 6–10. [CrossRef] [PubMed] 2. Garvey, W.T.; Mechanick, J.I.; Brett, E.M.; Garber, A.J.; Hurley, D.L.; Jastreboff, A.M.; Nadolsky, K.; Pessah-Pollack, R.; Plodkowski, R. American Association of Clinical Endocrinologists and American College of Endocrinology Comprehensive Clinical Practice Guidelines for Medical Care of Patients with Obesity. Endocr. Pract. 2016, 22, 842–884. [CrossRef] [PubMed] 3. Escobar-Morreale, H.F.; Santacruz, E.; Luque-Ramírez, M.; Botella Carretero, J.I. Prevalence of ‘Obesity-Associated Gonadal Dysfunction’ in Severely Obese Men and Women and Its Resolution after Bariatric Surgery: A Systematic Review and Meta- Analysis. Hum. Reprod. Update 2017, 23, 390–408. [CrossRef] 4. Gianatti, E.J.; Grossmann, M. Testosterone Deficiency in Men with Type 2 Diabetes: Pathophysiology and Treatment. Diabet. Med. 2020, 37, 174–186. [CrossRef] [PubMed] 5. Burschtin, O.; Wang, J. Testosterone Deficiency and Sleep Apnea. Sleep Med. Clin. 2016, 11, 525–529. [CrossRef] [PubMed] 6. Fernández-Miró, M.; Chillarón, J.J.; Pedro-Botet, J. Testosterone Deficiency, Metabolic Syndrome and Diabetes Mellitus|Déficit de Testosterona, Síndrome Metabólico y Diabetes Mellitus. Med. Clin. 2016, 146, 69–73. [CrossRef] 7. Kirby, M.; Hackett, G.; Ramachandran, S. Testosterone and the Heart. Eur. Cardiol. Rev. 2019, 14, 103–110. [CrossRef] 8. Wu, F.C.W.; Tajar, A.; Pye, S.R.; Silman, A.J.; Finn, J.D.; O’Neill, T.W.; Bartfai, G.; Casanueva, F.; Forti, G.; Giwercman, A.; et al. Hypothalamic-Pituitary-Testicular Axis Disruptions in Older Men Are Differentially Linked to Age and Modifiable Risk Factors: The European Male Aging Study. J. Clin. Endocrinol. Metab. 2008, 93, 2737–2745. [CrossRef] 9. Fernandez, C.J.; Chacko, E.C.; Pappachan, J.M. Male Obesity-Related Secondary Hypogonadism—Pathophysiology, Clinical Implications and Management. Eur. Endocrinol. 2019, 15, 83–90. [CrossRef] J. Clin. Med. 2022, 11, 5126 8 of 9 10. Dallal, R.M.; Chernoff, A.; O’Leary, M.P.; Smith, J.A.; Braverman, J.D.; Quebbemann, B.B. Sexual Dysfunction Is Common in the Morbidly Obese Male and Improves after Gastric Bypass Surgery. J. Am. Coll. Surg. 2008, 207, 859–864. [CrossRef] 11. Palmer, N.O.; Bakos, H.W.; Fullston, T.; Lane, M. Impact of Obesity on Male Fertility, Sperm Function and Molecular Composition. Spermatogenesis 2012, 2, 253–263. [CrossRef] [PubMed] 12. Sermondade, N.; Faure, C.; Fezeu, L.; Shayeb, A.G.; Bonde, J.P.; Jensen, T.K.; van Wely, M.; Cao, J.; Martini, A.C.; Eskandar, M.; et al. BMI in Relation to Sperm Count: An Updated Systematic Review and Collaborative Meta-Analysis. Hum. Reprod. Update 2013, 19, 221–231. [CrossRef] [PubMed] 13. Leisegang, K.; Roychoudhury, S.; Slama, P.; Finelli, R. The Mechanisms and Management of Age-Related Oxidative Stress in Male Hypogonadism Associated with Non-Communicable Chronic Disease. Antioxidants 2021, 10, 1834. [CrossRef] [PubMed] 14. Kwok, C.S.; Pradhan, A.; Khan, M.A.; Anderson, S.G.; Keavney, B.D.; Myint, P.K.; Mamas, M.A.; Loke, Y.K. Bariatric Surgery and Its Impact on Cardiovascular Disease and Mortality: A Systematic Review and Meta-Analysis. Int. J. Cardiol. 2014, 173, 20–22. [CrossRef] [PubMed] 15. Müller-Stich, B.P.; Senft, J.D.; Warschkow, R.; Kenngott, H.G.; Billeter, A.T.; Vit, G.; Helfert, S.; Diener, M.K.; Fischer, L.; Büchler, M.W.; et al. Surgical versus Medical Treatment of Type 2 Diabetes Mellitus in Nonseverely Obese Patients: A Systematic Review and Meta-Analysis. Ann. Surg. 2015, 261, 421–429. [CrossRef] 16. Corona, G.; Rastrelli, G.; Monami, M.; Saad, F.; Luconi, M.; Lucchese, M.; Facchiano, E.; Sforza, A.; Forti, G.; Mannucci, E.; et al. Body Weight Loss Reverts Obesity-Associated Hypogonadotropic Hypogonadism: A Systematic Review and Meta-Analysis. Eur. J. Endocrinol. 2013, 168, 820–843. [CrossRef] 17. Corona, G.; Rastrelli, G.; Morelli, A.; Sarchielli, E.; Cipriani, S.; Vignozzi, L.; Maggi, M. Treatment of Functional Hypogonadism besides Pharmacological Substitution. World J. Men’s Health 2019, 37, 256–270. [CrossRef] 18. Angulo, P.; Hui, J.M.; Marchesini, G.; Bugianesi, E.; George, J.; Farrell, G.C.; Enders, F.; Saksena, S.; Burt, A.D.; Bida, J.P.; et al. The NAFLD Fibrosis Score: A Noninvasive System That Identifies Liver Fibrosis in Patients with NAFLD. Hepatology 2007, 45, 846–854. [CrossRef] 19. Corcelles, R.; Boules, M.; Froylich, D.; Hag, A.; Daigle, C.R.; Aminian, A.; Brethauer, S.A.; Burguera, B.; Schauer, P.R. Total Weight Loss as the Outcome Measure of Choice After Roux-En-Y Gastric Bypass. Obes. Surg. 2016, 26, 1794–1798. [CrossRef] 20. Vermeulen, A.; Verdonck, L.; Kaufman, J.M. A Critical Evaluation of Simple Methods for the Estimation of Free Testosterone in Serum. J. Clin. Endocrinol. Metab. 1999, 84, 3666–3672. [CrossRef] 21. Travison, T.G.; Vesper, H.W.; Orwoll, E.; Wu, F.; Kaufman, J.M.; Wang, Y.; Lapauw, B.; Fiers, T.; Matsumoto, A.M.; Bhasin, S. Harmonized Reference Ranges for Circulating Testosterone Levels in Men of Four Cohort Studies in the United States and Europe. J. Clin. Endocrinol. Metab. 2017, 102, 1161–1173. [CrossRef] [PubMed] 22. Lu, J.C.; Huang, Y.F.; Lü, N.Q. WHO Laboratory Manual for the Examination and Processing of Human Semen: Its Applicability to Andrology Laboratories in China. Zhonghua Nan Ke Xue 2010, 16, 867–871. 23. Cooper, T.G.; Noonan, E.; von Eckardstein, S.; Auger, J.; Baker, H.W.G.; Behre, H.M.; Haugen, T.B.; Kruger, T.; Wang, C.; Mbizvo, M.T.; et al. World Health Organization Reference Values for Human Semen Characteristics. Hum. Reprod. Update 2009, 16, 231–245. [CrossRef] [PubMed] 24. Fernández, J.L.; Cajigal, D.; López-Fernández, C.; Gosálvez, J. Assessing Sperm DNA Fragmentation with the Sperm Chromatin Dispersion Test. Methods Mol. Biol. 2011, 682, 291–301. [CrossRef] [PubMed] 25. Rosen, R.C.; Riley, A.; Wagner, G.; Osterloh, I.H.; Kirkpatrick, J.; Mishra, A. The International Index of Erectile Function (IIEF): A Multidimensional Scale for Assessment of Erectile Dysfunction. Urology 1997, 49, 822–830. [CrossRef] 26. Sultan, S.; Patel, A.G.; El-Hassani, S.; Whitelaw, B.; Leca, B.M.; Vincent, R.P.; le Roux, C.W.; Rubino, F.; Aywlin, S.J.B.; Dimitriadis, G.K. Male Obesity Associated Gonadal Dysfunction and the Role of Bariatric Surgery. Front. Endocrinol. 2020, 11, 408. [CrossRef] 27. Lee, Y.; Dang, J.T.; Switzer, N.; Yu, J.; Tian, C.; Birch, D.W.; Karmali, S. Impact of Bariatric Surgery on Male Sex Hormones and Sperm Quality: A Systematic Review and Meta-Analysis. Obes. Surg. 2019, 29, 334–346. [CrossRef] 28. Glina, F.P.A.; de Freitas Barboza, J.W.; Nunes, V.M.; Glina, S.; Bernardo, W.M. What Is the Impact of Bariatric Surgery on Erectile Function? A Systematic Review and Meta-Analysis. Sex. Med. Rev. 2017, 5, 393–402. [CrossRef] 29. di Frega, A.S.; Dale, B.; di Matteo, L.; Wilding, M. Secondary Male Factor Infertility after Roux-En-Y Gastric Bypass for Morbid Obesity: Case Report. Hum. Reprod. 2005, 20, 997–998. [CrossRef] 30. Lazaros, L.; Hatzi, E.; Markoula, S.; Takenaka, A.; Sofikitis, N.; Zikopoulos, K.; Georgiou, I. Dramatic Reduction in Sperm Parameters Following Bariatric Surgery: Report of Two Cases. Andrologia 2012, 44, 428–432. [CrossRef] 31. Sermondade, N.; Massin, N.; Boitrelle, F.; Pfeffer, J.; Eustache, F.; Sifer, C.; Czernichow, S.; Lévy, R. Sperm Parameters and Male Fertility after Bariatric Surgery: Three Case Series. Reprod. Biomed. Online 2012, 24, 206–210. [CrossRef] [PubMed] 32. el Bardisi, H.; Majzoub, A.; Arafa, M.; AlMalki, A.; al Said, S.; Khalafalla, K.; Jabbour, G.; Basha, M.; al Ansari, A.; Sabanegh, E. Effect of Bariatric Surgery on Semen Parameters and Sex Hormone Concentrations: A Prospective Study. Reprod. Biomed. Online 2016, 33, 606–611. [CrossRef] 33. Samavat, J.; Cantini, G.; Lotti, F.; di Franco, A.; Tamburrino, L.; Degl’Innocenti, S.; Maseroli, E.; Filimberti, E.; Facchiano, E.; Lucchese, M.; et al. Massive Weight Loss Obtained by Bariatric Surgery Affects Semen Quality in Morbid Male Obesity: A Preliminary Prospective Double-Armed Study. Obes. Surg. 2018, 28, 69–76. [CrossRef] [PubMed] J. Clin. Med. 2022, 11, 5126 9 of 9 34. Legro, R.S.; Kunselman, A.R.; Meadows, J.W.; Kesner, J.S.; Krieg, E.F.; Rogers, A.M.; Cooney, R.N. Time-Related Increase in Urinary Testosterone Levels and Stable Semen Analysis Parameters after Bariatric Surgery in Men. Reprod. Biomed. Online 2015, 30, 150–156. [CrossRef] [PubMed] 35. Reis, L.O.; Zani, E.L.; Saad, R.D.; Chaim, E.A.; de Oliveira, L.C.; Fregonesi, A. Bariatric Surgery Does Not Interfere with Sperm Quality-a Preliminary Long-Term Study. Reprod. Sci. 2012, 19, 1057–1062. [CrossRef] [PubMed] 36. Carette, C.; Levy, R.; Eustache, F.; Baron, G.; Coupaye, M.; Msika, S.; Barrat, C.; Cohen, R.; Catheline, J.M.; Brugnon, F.; et al. Changes in Total Sperm Count after Gastric Bypass and Sleeve Gastrectomy: The BARIASPERM Prospective Study. Surg. Obes. Relat. Dis. 2019, 15, 1271–1279. [CrossRef] 37. Wood, G.J.A.; Tiseo, B.C.; Paluello, D.V.; de Martin, H.; Santo, M.A.; Nahas, W.; Srougi, M.; Cocuzza, M. Bariatric Surgery Impact on Reproductive Hormones, Semen Analysis, and Sperm DNA Fragmentation in Men with Severe Obesity: Prospective Study. Obes. Surg. 2020, 30, 4840–4851. [CrossRef] 38. Calderón, B.; Huerta, L.; Galindo, J.; González Casbas, J.M.; Escobar-Morreale, H.F.; Martín-Hidalgo, A.; Botella-Carretero, J.I. Lack of Improvement of Sperm Characteristics in Obese Males After Obesity Surgery Despite the Beneficial Changes Observed in Reproductive Hormones. Obes. Surg. 2019, 29, 2045–2050. [CrossRef] 39. Gao, Z.; Liang, Y.; Yang, S.; Zhang, T.; Gong, Z.; Li, M.; Yang, J. Bariatric Surgery Does Not Improve Semen Quality: Evidence from a Meta-Analysis. Obes. Surg. 2022, 32, 1341–1350. [CrossRef] 40. Andersen, E.; Juhl, C.R.; Kjøller, E.T.; Lundgren, J.R.; Janus, C.; Dehestani, Y.; Saupstad, M.; Ingerslev, L.R.; Duun, O.M.; Jensen, S.B.K.; et al. Sperm Count Is Increased by Diet-Induced Weight Loss and Maintained by Exercise or GLP-1 Analogue Treatment: A Randomized Controlled Trial. Hum. Reprod. 2022, 37, 1414–1422. [CrossRef] 41. Håkonsen, L.; Thulstrup, A.; Aggerholm, A.; Olsen, J.; Bonde, J.; Andersen, C.; Bungum, M.; Ernst, E.; Hansen, M.; Ernst, E.; et al. Does Weight Loss Improve Semen Quality and Reproductive Hormones? Results from a Cohort of Severely Obese Men. Reprod. Health 2011, 8, 24. [CrossRef] [PubMed] 42. Mir, J.; Franken, D.; Andrabi, S.W.; Ashraf, M.; Rao, K. Impact of Weight Loss on Sperm DNA Integrity in Obese Men. Andrologia 2018, 50, e12957. [CrossRef] [PubMed] 43. Calderón, B.; Hevia, V.; Vega-Piñero, B.; Martín-Hidalgo, A.; Mendez-del Sol, H.; Escobar-Morreale, H.F.; Botella-Carretero, J.I. Serum Retinol, Folic Acid, and Copper Are Associated With Sperm Abnormalities in Men With Obesity. J. Am. Coll. Nutr. 2018, 37, 194–200. [CrossRef] [PubMed] 44. Abiad, F.; Awwad, J.; Abbas, H.A.; Zebian, D.; Ghazeeri, G. Management of Weight Loss in Obesity-Associated Male Infertility: A Spotlight on Bariatric Surgery. Hum. Fertil. 2017, 20, 227–235. [CrossRef] 45. Reis, L.O.; Favaro, W.J.; Barreiro, G.C.; de Oliveira, L.C.; Chaim, E.A.; Fregonesi, A.; Ferreira, U. Erectile Dysfunction and Hormonal Imbalance in Morbidly Obese Male Is Reversed after Gastric Bypass Surgery: A Prospective Randomized Controlled Trial. Int. J. Androl. 2010, 33, 736–744. [CrossRef]