Well, this is interesting. It doesn't smell like bread, so yeast infection is out, discharge is worse after your period, so it isn't the hormonal influence, and it only smells after you have sex.
It sounds normal to me! Let me tell you why: the normal bacteria present in your vagina and your secretions, mixing with his secretions. This is very common. It has happened to me many times and I had the same question - and the GYN told me I had no infection.
If you have no chance of having an STD, this is normal.
Would LOVE to know what the GYN says about this. I think you will be fine.
Soap and water during daily baths should take care of this.
Hope this helps!
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