I am a 50-year-old male, and during intercourse, right before I am ready to ejaculate, I suffer from an excrutiating leg cramp which impairs my ability to finish the sexual act. This happens more and more frequently.
I know it has been a while since you posted, but I was wondering how you are doing. Did you ever get the opportunity to see a doctor? I am not a doctor and can't diagnose you, but I did want to know what kind of pain you are experiencing. Does it feel like a leg cramp you would get elswhere on your leg, or does it feel like it might be related to bloodflow in the pelvis? Either way, I think Paul is right that you should get checked out by your doctor.
Please consider returning to the community to let us know how things are going. I'm sure your experience could be a great help to others!
Best of luck,
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As above it may be worth consulting a doctor. The other thing to consider is do you use a similar sexual position all the time? If so then something as simple as changing position slightly could solve this.
Leg cramp happens when the muscles contract too hard. If the muscles are stretched taunt already then when you are close to ejaculating your body tenses up even more which causes the cramp.
Try change to a position where you don't have any strain on your leg and see if that helps. Also if you regularly get cramp in your leg anyway some gentle calf muscle stretches will help. The link below has information on leg cramps and a good stretching exercise.
Hope that helps.
I wonder if you see your doctor and discuss this with them. Perhaps there are some type of exercises you could do to preclude the cramping, or to make sure there is nothing physically wrong, of which this is a symptom.