Sexual intercourse is one of the most natural events in life, yet anecdotally it has also been associated with an increased risk of arrhythmia development, myocardial infarction or stroke. It has been suggested that elevations in sympathetic nerve activity (SNA) may mediate this increased cardiovascular risk. Thus an understanding of sympathetic outflow during coitus is liable to be important in recommending the safety of sexual activity in subjects with underlying cardiovascular disease. We have utilised a new telemetry technology to enable recordings of renal SNA, blood pressure and heart rate in male (n=5)and female rabbits (n=5) before, during and after mating. All procedures were approved by the University of Auckland Animal Ethics Committee. Rabbits underwent surgery to implant telemetry devices under isoflurane anaesthesia, at least 7 days prior to the experiment. Renal SNA was normalised to ganglionic blockade and the nasopharyngeal reflex response (0-100 normalised units, n.u.). ANOVA statistical analysis was performed (‡p<0.05). Sexual activity was associated with transient (8-14s) but extreme increases in renal SNA in both male (9±1 n.u. to 189±32 n.u.‡) and female (8±1 n.u. to 134±18 n.u.‡) rabbits. This increase was significantly greater than that observed during physical exertion immediately prior to mating (Male 27±6 n.u., Female 47±18 n.u.‡). Mean arterial pressure and heart rate also increased significantly during physical exertion in male (88±4 mmHg vs. 110±12 mmHg; 236±11 bpm vs. 312±18 bpm‡) and female rabbits (89±5 mmHg vs. 107±8 mHg; 247±9 bpm vs. 307±31 bpm‡), with further increases observed during mating (Male 134±9 mmHg, 422±21 bpm; Female 128±11 mmHg, 366±15 bpm‡). These results show sexual activity in healthy adult rabbits to be associated with profound transient increases in sympathetic drive to the kidneys, as well as significant increases on the workload of the heart as indicated by increases in heart rate and arterial pressure. Our study supports the hypothesis that sexual activity in subjects with underlying cardiovascular disease could carry an elevated degree of risk associated with the extreme increase in SNA.