High-intensity interval training modulates male factor infertility through anti-inflammatory and antioxidative mechanisms in infertile men: A randomized controlled trial

Protective Effect of Low-Volume High-Intensity Interval Training on Aspirin-Induced Reproductive Impairments in Adult Male Wistar Rats

Lifestyle factors such as sedentary behavior and consumption of certain medications can disturb the function of the male reproductive system. In the present study, we investigated the potential co-treatment effects of low-volume high-intensity interval training (HIIT) on markers of reproductive function in adult male Wistar rats under aspirin (ASA) treatment. Eighteen adult male Wistar rats were randomized into three groups: control (C), aspirin treatment (AT), and aspirin treatment + exercise (ATE). Animals in the AT and ATE groups received an oral subchronic dose of aspirin (12.5 mg/kg body mass). The exercise was performed three times per week for 6 weeks (4-6 reps of 10-s sprints). Serum testosterone level, sperm parameters (sperm count, viability, maturity, and DNA fragmentation), histomorphometric (Leydig cell, tubule diameter, thickness of tubular epithelium, and indices of spermatogenesis and spermiogenesis), and histochemical parameter (testicular fat density) were assessed. Results revealed that compared to the C group, ASA consumption led to a negative alteration in serum testosterone levels, sperm parameters, and histomorphometric and histochemical parameters (P < 0.05). However, there were no significant differences between the C and ATE groups in terms of serum testosterone level, number of Leydig cells, epididymal fat density, tubule diameter, epithelium height, immature-to-mature sperm ratio, and DNA breakage (P > 0.05). These findings suggest that ASA treatment is associated with deleterious changes in male reproductive parameters. However, low-volume HIIT may prevent ASA-induced male reproductive impairments and could be considered a potential prophylactic measure in subjects under ASA treatment.

Changes in pain perception during pregnancy after one-time maximal physical exertion and an 8-week high-intensity interval training

Background: Pain, a subjective sensation, poses a great challenge to the human body as a stressor. There is empirical evidence that moderate to intense physical activity increases pain tolerance and this may be critical during pregnancy for optimal pregnancy, fetal development, and delivery. To the best of our knowledge, it is the first study examining the changes in pain perception in pregnant women after a maximal progressive exercise test and after 8 weeks of high-intensity interval training (HIIT). Methods: Thirty-five women with uncomplicated singleton pregnancies between 13 and 28 weeks of gestation participated in the study. The HIIT intervention was developed in accordance with the recommendations and available data on HIIT during pregnancy. The maximal progressive cardiopulmonary exercise test was performed on a cycle ergometer with an electronically controlled load. Pressure pain threshold and pressure pain tolerance were measured with an algometer. Results: We found significant effects of the maximal exercise test and high-intensity interval training, such that the pregnant women had higher pain tolerance after the maximal exercise test than before and after the high-intensity interval training than the baseline. Conclusion: Our results suggest that post-exercise analgesia may be important in pregnant women and that high-intensity interval training appears to be beneficial for pregnant women to improve their pain tolerance while being obstetrically safe. Increased pain tolerance before labor could lead to better management of pain during labor and in the postpartum and lactation periods. Increasing pregnant women's awareness of this issue can improve their wellbeing and provide more comfort during labor.

Impact of Physical Activity and Sedentary Behavior on Spontaneous Female and Male Fertility: A Systematic Review

BACKGROUND

Before pregnancy is recognized, ovulation, fertilization, and implantation must all occur. Physical activity and sedentary behavior may impact pregnancy success by altering each or all of these processes. The aim of this review was to review the association between physical activity and sedentary behavior with spontaneous female and male fertility.

METHOD

PubMed/MEDLINE, Web of Science, CINAHL, SPORTDiscus, and Embase were searched from inception to August 9, 2021. Eligible studies included randomized controlled trials or observational studies, published in English, describing an association between physical activity or sedentary behavior (exposures) and spontaneous fertility (outcome) among women or men.

RESULTS

Thirty-four studies from 31 unique populations were included in this review (12 cross-sectional studies, 10 cohort studies, 6 case-control studies, 5 randomized controlled trials, and one case-cohort study). Of the 25 studies among women, the majority identified mixed results (n = 11) or no association (n = 9) between physical activity and female fertility. Seven studies reported on female fertility and sedentary behavior, and 2 found sedentary behavior was associated with decreased female fertility. Of the 11 studies among men, most of the studies (n = 6) found that physical activity was associated with increased male fertility. Two of the studies reported on male fertility and sedentary behavior, and neither identified an association.

CONCLUSIONS

The association between spontaneous fertility and physical activity in both men and women remains unclear, and the association with sedentary behavior remains largely unexplored.

Effectiveness of non-pharmaceutical intervention on sperm quality: a systematic review and network meta-analysis

Infertility affects about 10% of the world's population and has been recognized by the WHO as a global public health problem. The aim of this network meta-analysis was to investigate the efficacy of non-pharmaceutical interventions on sperm quality. All randomized clinical trials (RCTs) from the PubMed, MEDLINE, Embase, China national knowledge infrastructure (CNKI), Wanfang database, and Cochrane Library databases evaluating the effectiveness of non-pharmaceutical interventions on semen parameters using network meta-analyses. Results of the ω-3 fatty acid, lycopene, acupuncture, and vitamin suggested evident advantages in improving sperm concentration (MD, 9.93 (95% CI, 7.21 to 12.65)), (MD, 8.79 (95% CI, 2.67 to 14.91)), (MD, 5.40 (95% CI, 2.32 to 8.49)) and (MD, 3.82 (95% CI, 0.70 to 6.94) respectively). Acupuncture has a significant advantage over placebo in improving sperm total motility (MD, 17.81 (95% CI, 10.32 to 25.29)), and the effect of lycopene was obviously greater than that of placebo (MD, 19.91 (95% CI, 2.99 to 36.83)). Lycopene, Coenzyme Q10 (CoQ10), acupuncture, ω-3 fatty acid, and vitamin suggested significant advantages in improving sperm forward motility (MD, 8.64 (95% CI, 1.15 to 16.13), MD, 5.28 (95% CI, 2.70 to 7.86), MD, 3.95 (95% CI, 3.23 to 4.67), MD, 3.50 (95% CI, 2.21 to 4.79)) and (MD, 2.38 (95% CI, 0.96 to 3.80) respectively). This review establishes that non-pharmaceutical interventions, particularly acupuncture, exercise, lycopene, ω-3 fatty acids, CoQ10, zinc, vitamins, selenium, carnitine, or foods rich in these supplements, profitably improve sperm quality that may be used to treat male infertility.

Lifestyle-, environmental-, and additional health factors associated with an increased sperm DNA fragmentation: a systematic review and meta-analysis

INTRODUCTION

Infertility affects one in every six couples in developed countries, and approximately 50% is of male origin. In 2021, sperm DNA fragmentation (SDF) testing became an evidence-based test for fertility evaluations depicting fertility more clearly than standard semen parameters. Therefore, we aimed to summarize the potential prognostic factors of a higher SDF.

METHODS

We conducted a systematic search in three medical databases and included studies investigating any risk factors for SDF values. We calculated mean differences (MD) in SDF with 95% confidence interval (CI) for exposed and non-exposed individuals.

RESULTS

We included 190 studies in our analysis. In the group of associated health conditions, varicocele (MD = 13.62%, CI: 9.39-17.84) and impaired glucose tolerance (MD = 13.75%, CI: 6.99-20.51) had the most significant increase in SDF. Among malignancies, testicular tumors had the highest impact, with a maximum of MD = 11.3% (CI: 7.84-14.76). Among infections, the overall effects of both Chlamydia and HPV were negligible. Of lifestyle factors, smoking had the most disruptive effect on SDF - an increase of 9.19% (CI: 4.33-14.06). Different periods of sexual abstinence did not show significant variations in SDF values. Age seemed to have a more drastic effect on SDF from age 50 onwards, with a mean difference of 12.58% (CI: 7.31-17.86). Pollution also had a detrimental effect - 9.68% (CI: 6.85-12.52).

CONCLUSION

Of the above risk factors, varicocele, impaired glucose tolerance, testicular tumors, smoking, pollution, and paternal age of over 50 were associated with the highest SDF.

TRIAL REGISTRATION

CRD42021282533.

Male Fertility and Physical Exercise

According to existing studies, sedentary behavior contributes to male infertility. Both preclinical and clinical studies have investigated the association between physical exercise, semen quality, and pregnancy rates with heterogeneous results. The current review sought to examine the relationship between physical activity (PA) and male infertility, semen characteristics, and pregnancy rates. Pre-clinical studies demonstrated mixed benefits from exercise, with diet being an important consideration. Some forms of PA showed an improvement in pregnancy rates, while others did not consistently improve semen quality. Data also suggests that more intense exercise and certain types of exercise may impair male fertility. Given the limited number of randomized trials, future research is required to examine the relationship between specific forms of exercise and semen parameters along with reproductive outcomes.

Infertility in Men: Advances towards a Comprehensive and Integrative Strategy for Precision Theranostics

Male infertility is an increasing and serious medical concern, though the mechanism remains poorly understood. Impaired male reproductive function affects approximately half of infertile couples worldwide. Multiple factors related to the environment, genetics, age, and comorbidities have been associated with impaired sperm function. Present-day clinicians rely primarily on standard semen analysis to diagnose male reproductive potential and develop treatment strategies. To address sperm quality assessment bias and enhance analysis accuracy, the World Health Organization (WHO) has recommended standardized sperm testing; however, conventional diagnostic and therapeutic options for male infertility, including physical examination and semen standard analysis, remain ineffective in relieving the associated social burden. Instead, assisted reproductive techniques are becoming the primary therapeutic approach. In the post-genomic era, multiomics technologies that deeply interrogate the genome, transcriptome, proteome, and/or the epigenome, even at single-cell level, besides the breakthroughs in robotic surgery, stem cell therapy, and big data, offer promises towards solving semen quality deterioration and male factor infertility. This review highlights the complex etiology of male infertility, especially the roles of lifestyle and environmental factors, and discusses advanced technologies/methodologies used in characterizing its pathophysiology. A comprehensive combination of these innovative approaches in a global and multi-centric setting and fulfilling the suitable ethical consent could ensure optimal reproductive and developmental outcomes. These combinatorial approaches should allow for the development of diagnostic markers, molecular stratification classes, and personalized treatment strategies. Since lifestyle choices and environmental factors influence male fertility, their integration in any comprehensive approach is required for safe, proactive, cost-effective, and noninvasive precision male infertility theranostics that are affordable, accessible, and facilitate couples realizing their procreation dream.

Acetylsalicylic acid-induced alterations in male reproductive parameters in Wistar rats and the effect of sprint interval training

The present study investigated the effect of a 5-week ASA treatment on male reproductive parameters in Wistar rats; moreover, the potential benefits of a 4-week sprint interval training (SIT) on these measures following ASA treatment were investigated. A total of 25 male rats were obtained and randomly assigned to the control group (C, n = 10) and the ASA treatment group (EP, n = 15). After 5 weeks, five rats from each group were killed and the effect of ASA treatment on the reproductive parameters was assessed. Then, the ASA treatment terminated and the remaining 10 ASA-treated rats were divided into the non-treatment group (NT, n = 5) and the exercise training group (ET, n = 5), which performed SIT 3 sessions/week for 4 weeks. Five weeks of ASA treatment resulted in a statistically significant decrease in serum testosterone level, Leydig cell number, sperm count, sperm motility, sperm viability, TDI, SI and RI, and it resulted in a significant increase in sperm nucleus maturity and sperm DNA fragmentation (p ˂ 0.05). Furthermore, 4 weeks of SIT reversed all the ASA-induced changes in male reproductive parameters (p < 0.05), but not the number of seminiferous tubules and the sperm motility (p > 0.05). A subchronic dose of ASA could lead to adverse alterations in male reproductive parameters and SIT is beneficial in reversing those alterations.

Outcome reporting across randomized controlled trials evaluating potential treatments for male infertility: a systematic review

STUDY QUESTION

What are the primary outcomes and outcome measures used in randomized controlled trials (RCTs) evaluating potential treatments for male infertility in the last 10 years?

SUMMARY ANSWER

Outcome reporting across male infertility trials is heterogeneous with numerous definitions and measures used to define similar outcomes.

WHAT IS KNOWN ALREADY

No core outcome set for male infertility trials has been developed. Male infertility trials are unique in that they have potentially three participants, a man, a female partner and their offspring and this will likely lead to significant variation in outcome reporting in randomized trials.

STUDY DESIGN SIZE DURATION

A systematic review of RCTs mapping outcomes and outcome measures evaluating potential treatments for men with infertility registered in the Cochrane Register of Controlled Trials (CENTRAL) between January 2010 and July 2021.

PARTICIPANTS/MATERIALS SETTING METHODS

Abstract screening and study selection was undertaken in duplicate using a review protocol that was developed prior to commencing the review. No risk of bias assessment was undertaken as this review aims to report on outcome reporting only.

MAIN RESULTS AND THE ROLE OF CHANCE

One hundred and seventy-five RCTs were identified, and given the large number of studies we limited our review to the 100 largest trials. Seventy-nine different treatments were reported across the 100 largest RCTs including vitamin and dietary supplements (18 trials), surgical treatments (18 trials) and sperm selection techniques (22 trials). When considering the largest 100 trials (range: 80-2772 participants), 36 primary and 89 secondary outcomes were reported. Forty-seven trials reported a primary outcome and 36 trials clearly defined their primary outcome. Pregnancy outcomes were inconsistently reported and included pregnancy rate (51 trials), pregnancy loss including miscarriage, ectopic pregnancy, stillbirth (9 trials) and live birth (13 trials). Trials consistently reporting the same outcome frequently used different definitions. For example, semen quality was reported by 75 trials and was defined in 7 different ways, including; the World Health Organization (WHO) 2010 criteria (32 trials), WHO 1999 criteria (18 trials), WHO 1992 criteria (3 trials), WHO 1999 and 1992 criteria (1 trial) and the Kruger strict morphology criteria (1 trial).

LIMITATIONS REASONS FOR CAUTION

We only evaluated the 100 largest trials published in the last 10 years and did not report outcomes on the remaining 75. An outcome was included as a primary outcome only if clearly stated in the manuscript and we did not contact authors to clarify this. As our review mapped outcomes and outcome measures, we did not undertake an integrity assessment of the trials included in our review.

WIDER IMPLICATIONS OF THE FINDINGS

Most randomized trials evaluating treatments for male infertility report different outcomes. Only half of the RCTs reported pregnancy rate and even fewer reported live birth; furthermore, the definitions of these outcomes varies across trials. Developing, disseminating and implementing a minimum data set, known as a core outcome set, for male infertility research could help to improve outcome selection, collection and reporting.

STUDY FUNDING/COMPETING INTERESTS

A.P.-chairman of external scientific advisory committee of Cryos International Denmark ApS, member of the scientific advisory board for Cytoswim LDT and ExSeed Health. Guest lecture at the 'Insights for Fertility Conference', funded by MERK SERONO Limited. M.v.W.-holds a ZON-MW research grant. No external funding was obtained for this study.

Effectiveness of Exercise Training on Male Factor Infertility: A Systematic Review and Network Meta-analysis

CONTEXT

Mounting evidence from the literature suggests that different types of training interventions can be successful at improving several aspects of male reproductive function in both fertile and infertile populations.

OBJECTIVE

The aim of this study was to evaluate the effectiveness of exercise training on male factor infertility and seminal markers of inflammation.

DATA SOURCES

We searched PubMed, CISCOM, Springer, Elsevier Science, Cochrane Central Register of Controlled Trials, Scopus, PEDro, Ovid (Medline, EMBASE, PsycINFO), Sport Discus, Orbis, CINAHL, Web of Science, ProQuest, and the ClinicalTrials.gov registry for randomized controlled trials (RCTs) that analyzed the impacts of selected types of exercise interventions on markers of male reproductive function and reproductive performance.

STUDY SELECTION

A total of 336 records were identified, of which we included 7 trials reporting on 2641 fertile and infertile men in the systematic review and network meta-analysis.

LEVEL OF EVIDENCE

Level 1 (because this is a systematic review of RCTs).

DATA EXTRACTION

The data included the study design, participant characteristics, inclusion and exclusion, intervention characteristics, outcome measures, and the main results of the study.

RESULTS

The results of network meta-analysis showed that, compared with a nonintervention control group, the top-ranking interventions for pregnancy rate were for combined aerobic and resistance training (CET) (relative risk [RR] = 27.81), moderate-intensity continuous training (MICT) (RR = 26.67), resistance training (RT) (RR = 12.54), high-intensity continuous training (HICT) (RR = 5.55), and high-intensity interval training (HIIT) (RR = 4.63). While the top-ranking interventions for live birth rate were for MICT (RR = 10.05), RT (RR = 4.92), HIIT (RR = 4.38), CET (RR = 2.20), and HICT (RR = 1.55). Also, with the following order of effectiveness, 5 training strategies were significantly better at improving semen quality parameters (CET > MICT > HICT > RT > HIIT), seminal markers of oxidative stress (CET > MICT > HIIT > HICT > RT), seminal markers of inflammation (CET > MICT > HIIT > RT > HICT), as well as measures of body composition and VO₂max (CET > HICT > MICT > HIIT > RT).

CONCLUSION

The review recommends that the intervention with the highest probability of being the best approach out of all available options for improving the male factor infertility was for CET.

Acute effect of high-intensity interval training exercise on redox status in the ovaries of rats fed a high-fat diet

This study demonstrates the effect of a single high-intensity interval training (HIIT) session on the redox status of rat ovaries with excess adiposity. Forty Wistar female rats (mean (±s.e.m.) weight 94.40 ± 13.40 g) were divided into two groups and fed either a standard diet (SD) or a high-fat diet (HFD) for 62 days. At the end of this period, the rats were subjected to a single HIIT session and were killed 24 h after exercise. Both groups subjected to exercise (SDex and HFDex) generated a significantly higher antioxidant environment by presenting a higher thiol content, which represents a lower oxidation rate of GSH than their respective controls (SD and HFD). The percentage of morphologically normal primary follicles decreased, whereas that of antral follicles increased, in the SDex group. In addition, the HFD group had a higher percentage of degenerated antral follicles than the SD and SDex groups. Cells immunoreactive for α-smooth muscle actin were seen in the cortical stroma and thecal layer enclosing late secondary and tertiary follicles in all groups. Moreover, heme oxygenase and cytochrome P450 family 19 subfamily A member 1 (Cyp19A1) labelling was seen in all antral follicles. Progesterone concentrations were significantly higher in the HFDex than SDex group. In conclusion, this study indicates that a single session of HIIT may result in an improvement in ovary redox status because of metabolic muscle activity by inducing physiological adaptation after exercise in a paracrine manner.

Antioxidant Effects of Aerobic Training and Crocin Consumption on Doxorubicin-Induced Testicular Toxicity in Rats

Objective: Doxorubicin (DOX) treatment has been reported to increase the risk of serious toxicity in testis, therefore the aim of the present study was to investigate the antioxidant effects of training and Crocin on doxorubicin-induced testicular toxicity in rats.

Materials and methods:⊆_max) 5 day/w. Also, groups 2 to 7 administered 2 mg/kg/w DOX intraperitoneal. The testes were removed and glutathione peroxidase (GP_X), total antioxidant capacity (TAC) and protein carbonyl (PC) were analyzed using ELISA methods, one-way analysis of variance along with Bonferroni’s post hoc test were used for analysis in SPSS (P≤0.05).

Results: The results of the present study showed that doxorubicin induced oxidative stress in testicular tissue by decreasing the level of GPX and TAC and increasing PC level (P≤0.05); TAC and GPX improved in all groups except groups 2 and 5, respectively, and their increase in the group 7 was significantly higher compared to other groups (P≤0.05). Increased PC levels were significantly reduced in the groups 5, 6 and 7.

Conclusion: The increase in antioxidant levels in the concurrent Crocin and training group seems to be dose-dependent, but the oxidative stress in both Crocin and training groups of 10 and 50 mg/kg/d is associated with a decrease, but its modulation in the Crocin consumption group alone depends on the dose.

Preconception lifestyle advice for people with infertility

BACKGROUND

Infertility is a prevalent problem that has significant consequences for individuals, families, and the community. Modifiable lifestyle factors may affect the chance of people with infertility having a baby. However, no guideline is available about what preconception advice should be offered. It is important to determine what preconception advice should be given to people with infertility and to evaluate whether this advice helps them make positive behavioural changes to improve their lifestyle and their chances of conceiving.

OBJECTIVES

To assess the safety and effectiveness of preconception lifestyle advice on fertility outcomes and lifestyle behavioural changes for people with infertility.

SEARCH METHODS

We searched the Cochrane Gynaecology and Fertility Group Specialised Register of controlled trials, CENTRAL, MEDLINE, Embase, PsycINFO, AMED, CINAHL, trial registers, Google Scholar, and Epistemonikos in January 2021; we checked references and contacted field experts to identify additional studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs), randomised cross-over studies, and cluster-randomised studies that compared at least one form of preconception lifestyle advice with routine care or attention control for people with infertility.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures recommended by Cochrane. Primary effectiveness outcomes were live birth and ongoing pregnancy. Primary safety outcomes were adverse events and miscarriage. Secondary outcomes included reported behavioural changes in lifestyle, birth weight, gestational age, clinical pregnancy, time to pregnancy, quality of life, and male factor infertility outcomes. We assessed the overall quality of evidence using GRADE criteria.

MAIN RESULTS

We included in the review seven RCTs involving 2130 participants. Only one RCT included male partners. Three studies compared preconception lifestyle advice on a combination of topics with routine care or attention control. Four studies compared preconception lifestyle advice on one topic (weight, alcohol intake, or smoking) with routine care for women with infertility and specific lifestyle characteristics. The evidence was of low to very low-quality. The main limitations of the included studies were serious risk of bias due to lack of blinding, serious imprecision, and poor reporting of outcome measures. Preconception lifestyle advice on a combination of topics versus routine care or attention control Preconception lifestyle advice on a combination of topics may result in little to no difference in the number of live births (risk ratio (RR) 0.93, 95% confidence interval (CI) 0.79 to 1.10; 1 RCT, 626 participants), but the quality of evidence was low. No studies reported on adverse events or miscarriage. Due to very low-quality evidence, we are uncertain whether preconception lifestyle advice on a combination of topics affects lifestyle behavioural changes: body mass index (BMI) (mean difference (MD) -1.06 kg/m², 95% CI -2.33 to 0.21; 1 RCT, 180 participants), vegetable intake (MD 12.50 grams/d, 95% CI -8.43 to 33.43; 1 RCT, 264 participants), alcohol abstinence in men (RR 1.08, 95% CI 0.74 to 1.58; 1 RCT, 210 participants), or smoking cessation in men (RR 1.01, 95% CI 0.91 to 1.12; 1 RCT, 212 participants). Preconception lifestyle advice on a combination of topics may result in little to no difference in the number of women with adequate folic acid supplement use (RR 0.98, 95% CI 0.95 to 1.01; 2 RCTs, 850 participants; I² = 4%), alcohol abstinence (RR 1.07, 95% CI 0.99 to 1.17; 1 RCT, 607 participants), and smoking cessation (RR 1.01, 95% CI 0.98 to 1.04; 1 RCT, 606 participants), on low quality evidence. No studies reported on other behavioural changes. Preconception lifestyle advice on weight versus routine care Studies on preconception lifestyle advice on weight were identified only in women with infertility and obesity. Compared to routine care, we are uncertain whether preconception lifestyle advice on weight affects the number of live births (RR 0.94, 95% CI 0.62 to 1.43; 2 RCTs, 707 participants; I² = 68%; very low-quality evidence), adverse events including gestational diabetes (RR 0.78, 95% CI 0.48 to 1.26; 1 RCT, 317 participants; very low-quality evidence), hypertension (RR 1.07, 95% CI 0.66 to 1.75; 1 RCT, 317 participants; very low-quality evidence), or miscarriage (RR 1.50, 95% CI 0.95 to 2.37; 1 RCT, 577 participants; very low-quality evidence). Regarding lifestyle behavioural changes for women with infertility and obesity, preconception lifestyle advice on weight may slightly reduce BMI (MD -1.30 kg/m², 95% CI -1.58 to -1.02; 1 RCT, 574 participants; low-quality evidence). Due to very low-quality evidence, we are uncertain whether preconception lifestyle advice affects the percentage of weight loss, vegetable and fruit intake, alcohol abstinence, or physical activity. No studies reported on other behavioural changes. Preconception lifestyle advice on alcohol intake versus routine care Studies on preconception lifestyle advice on alcohol intake were identified only in at-risk drinking women with infertility. We are uncertain whether preconception lifestyle advice on alcohol intake affects the number of live births (RR 1.15, 95% CI 0.53 to 2.50; 1 RCT, 37 participants; very low-quality evidence) or miscarriages (RR 1.31, 95% CI 0.21 to 8.34; 1 RCT, 37 participants; very low-quality evidence). One study reported on behavioural changes for alcohol consumption but not as defined in the review methods. No studies reported on adverse events or other behavioural changes. Preconception lifestyle advice on smoking versus routine care Studies on preconception lifestyle advice on smoking were identified only in smoking women with infertility. No studies reported on live birth, ongoing pregnancy, adverse events, or miscarriage. One study reported on behavioural changes for smoking but not as defined in the review methods.

AUTHORS' CONCLUSIONS

Low-quality evidence suggests that preconception lifestyle advice on a combination of topics may result in little to no difference in the number of live births. Evidence was insufficient to allow conclusions on the effects of preconception lifestyle advice on adverse events and miscarriage and on safety, as no studies were found that looked at these outcomes, or the studies were of very low quality. This review does not provide clear guidance for clinical practice in this area. However, it does highlight the need for high-quality RCTs to investigate preconception lifestyle advice on a combination of topics and to assess relevant effectiveness and safety outcomes in men and women with infertility.