La ricerca dell'Università di Padova
Troppa sauna rende gli uomini poco fertili
L'aumento della temperatura dei testicoli può ridurre la produzione degli spermatozoi. Ma è un effetto reversibile

MILANO - La sauna troppo frequente non fa bene alla fertilità: nell'arco di tre mesi può aumentare la temperatura dei testicoli e dimezzare la produzione degli spermatozoi. È quanto è stato osservato nella ricerca condotta nell'università di Padova e presentata nel convegno sulla Medicina della sessualità in corso ad Abano Terme (Padova).

LA RICERCA - In condizioni normali la temperatura dei testicoli è di 2 gradi inferiore a quella corporea, fattore fondamentale per una normale produzione degli spermatozoi, spiegano i ricercatori, coordinati da Carlo Foresta. È inoltre noto da tempo che il calore ha un effetto negativo sulla fertilità e la conferma ulteriore è arrivata dallo studio di 10 giovani che si sono sottoposti a sedute di sauna di un quarto d'ora ciascuna due volte alla settimana per tre mesi. Si è osservato così un aumento di due gradi della temperatura dei testicoli e che nell'arco di tre mesi la produzione di spermatozoi nel campione preso in esame si era più che dimezzata. La situazione, osservano i ricercatori, è reversibile grazie all'azione di molecole riparatrici, capaci di contrastare gli effetti negativi del calore. (Fonte: Ansa)

26 febbraio 2010

Sarà vero che troppa sauna può far diminuire gli spermatozoi?

Andrologia. 2007 Dec;39(6):203-15.

Influence of genital heat stress on semen quality in humans.
Jung A, Schuppe HC.

Center of Dermatology and Andrology, Justus Liebig University, Giessen, Germany. Andreas.Jung@derma.med.uni-giessen.de

The concept that an elevation of testicular temperature results in impairment of spermatogenesis is widely accepted. Here, current knowledge concerning genital heat stress and its consequences in men is reviewed. Duration of sitting during work positively correlates with daytime scrotal temperatures and daytime scrotal temperature negatively correlates with semen quality. However, the assumed negative correlation between duration of sitting and semen quality could not be shown in the available studies. Fertility parameters of professional drivers with long periods of sitting in vehicles were impaired; however, for predominantly affected drivers of vans, trucks or industrial heavy machinery potential confounders have to be considered. Wearing tight fitting compared with loose-fitting underwear is associated with significantly higher scrotal temperatures. However, available observations suggesting a link between tight-fitting underwear or trousers and impaired semen quality are not convincing. Studies addressing professional exposure to high temperatures delivered conflicting results concerning fertility parameters. The postulated negative impact of sauna visits on semen quality is not sufficiently underlined by the available studies. Oligozoospermic men with a varicocele have significantly higher scrotal temperatures than normozoospermic men, and according to several studies varicocelectomy normalises scrotal temperatures. A further link has been reported between fever and deteriorated semen quality. Contraception via genital heat stress has been demonstrated using hot sitting baths or insulating suspensors. However, down-regulation of spermatogenesis is inconsistent and unsafe. On the other hand, scrotal and consecutively testicular cooling is able to improve semen quality.

PMID: 18076419 [PubMed - indexed for MEDLINE]

Am J Med. 2001 Feb 1;110(2):118-26.

Benefits and risks of sauna bathing.
Hannuksela ML, Ellahham S.

Department of Internal Medicine and Biocenter Oulu (MLH), University of Oulu, Oulu, Finland.

Although sauna bathing causes various acute, transient cardiovascular and hormonal changes, it is well tolerated by most healthy adults and children. Sauna bathing does not influence fertility and is safe during the uncomplicated pregnancies of healthy women. Some studies have suggested that long-term sauna bathing may help lower blood pressure in patients with hypertension and improve the left ventricular ejection fraction in patients with chronic congestive heart failure, but additional data are needed to confirm these findings. The transient improvements in pulmonary function that occur in the sauna may provide some relief to patients with asthma and chronic bronchitis. Sauna bathing may also alleviate pain and improve joint mobility in patients with rheumatic disease. Although sauna bathing does not cause drying of the skin-and may even benefit patients with psoriasis-sweating may increase itching in patients with atopic dermatitis. Contraindications to sauna bathing include unstable angina pectoris, recent myocardial infarction, and severe aortic stenosis. Sauna bathing is safe, however, for most people with coronary heart disease with stable angina pectoris or old myocardial infarction. Very few acute myocardial infarctions and sudden deaths occur in saunas, but alcohol consumption during sauna bathing increases the risk of hypotension, arrhythmia, and sudden death, and should be avoided.

PMID: 11165553 [PubMed - indexed for MEDLINE]