vio,
Recently, i was doing some reading online about infertility. Then hor, they were citing the reasons of infertility in women. One of them being low in hormones. Actually hor ... sometimes, the egg really does get fertilized leh, but just doesn't get implanted to the uterus lining. Well, in TCM terms, they probably refer it to the womb too cold or weak, that's why egg cannot stick. In western medical terms, it's because we have low hormones.
So a lot of us out there, sometimes wonder why we are infertile and think could it be never O or sperm not strong enough. But there could also be a situation where the sperm did meet the egg and got it fertilized, just that it didn't have uterus lining strong enough to get implanted. Very sad hor? Then, there was another symptom I read which was that the uterus or egg (cannot remember which is which) has a bacteria that automatically kills sperms. So hor, even when the sperms are such strong swimmers, also no use, coz' the moment they enter the uterus, they'll get killed by the bacteria. I mean such things how we know right?
Unless do really detailed body checks.