Many women never learn of the
three bedikot requirement. This is more often the case for women from America, where common practice is to rely on the position of Rav Moshe Feinstein, who ruled in accordance with the opinion that these
bedikot are not required unless a problem arises.
Your years of marital relations without incident have halachic weight. When a couple has been married for some time without any bleeding incidents subsequent to marital relations, most halachic decisors waive the requirement. Ten years is more than enough time.
Among Sephardi poskim, Rav Ovadiah Yosef is stringent even with a couple that has been married for a long time, but accepts even an external wiping as a
bedikah. Thus, your experiences with the diaphragm should satisfy even his stringent opinion.
We recommend in the future rinsing off the diaphragm without looking for any discharge, since blood found on a diaphragm is generally treated stringently, without leniencies, unlike
stains found externally.
