Praise God! The heartbeat is 168, measuring at exactly 8 weeks (which is right where I was thinking I ought to be). The RE said "things can't look more normal than that".
I realize that we still have a long way to go, but this is a huge milestone. Thank you so much for all of your prayers. Please keep them coming in the weeks and months to come.
What an amazing blessing to see the heart just "thump, thump, thumping" away! And what a blessing to see my husband's relief quickly change to excitement. Praise God!