How can a woman still receive her period if she have her tubes tied?

doesnt that block offthe disolving egg (aka the period)?
Answers:

Your period is not a dissolving egg; it's the pool liner of your uterus sloughing off. All aspects of your cycle, from ovulation to the buildup of your uterine facing and its eventual sloughing off, are controlled by hormones. Blocking the egg's street from the ovary to the uterus does not alter your hormonal pattern, so your cycle still works like peas in a pod. The only difference is that the unfertilized egg is reabsorbed into your body (like any unmoving cell) instead of exiting with your uterine pool liner.

What is a fast mode to work your lower abs and see results?

The egg is still released it just can't acquire to the uterus so the lining that have been built up is still shed respectively month.

Can you keep the Nuvaring in..?

Each month the uterus is prepared for possible pregnancy - the pool liner thickens and blood is pumped into the tissue to create a cushioned place for the toddler.
Then an egg is released from the ovaries.
If the egg is not fertilised the lining of the uterus and teh unfertised egg are shed as the spell.

When your tubes are tied, the uterus still prepares itself, so you have a buildup of tissue and blood. The egg doesn't acquire to the uterus and dissolves in the fallopian tubes. The bin liner of the uterus is still shed as the period. That's what adjectives the blood it, not the egg - the egg is microscopic.