Neda, Hot packs on the belly are recommended extremely widely for self-treatment of period pain. I am not aware of any research which has indicated an adverse effect on a woman's eggs, but there is widely accepted research indicating that excess heat is not good for sperm. I think your hubby might be thinking that's what's good for the goose is good for the gander, but in this case, our reproductive systems have very different needs and very different arrangements (male - external, female - internal.) You couldn't find evidence that it was bad for you because it's not bad for you!

On the other hand, it's really sweet that doesn't like seeing you stress, and that he cares enough to think about it, although in this point he's on the wrong track. Unfounded concerns should not stop you from using heat as a safe and effective form of pain control. I have read some of your other posts - I think it is time to see a FS again about what the next step on your ttc journey should be.

Also, I will pm you a few links to papers which discuss depth of penetration of various heating modalities - they include references to deep heat modalities like diathermy and ultrasound, whhich do not apply to hot packs. You need to be reading the bits referring to 'superficial heat application', 'Thermotherapy - superficial heating agents', etc. In summary, you get tissue temperature changes mostly in the first half centimeter, and after longer applications, it can penetrate futher (eg, up to 1 or 2 cm, depending on what you read), however, the change in temp is very low as you go deeper than 1 cm. And fat is an insulator, so areas with more fat (like the standard, healthy layer of fat all women of healthy weight carry over their lower belly) have much less depth of penetration.

Please stop worrying - you have not roasted your eggies!!