I use and recommend/rave about/swear by a bodyCushion
Best thing for massage I've ever purchased, paid for itself thousands of times over (I've had mine for over 10years, and still going strong) I got mine online from US last century when buying things over $100 online was pretty uncommon. I am so glad I did!
It's also extremely comfortable for any one with a large chest, natural or implants, and when I did some damage to L5-S1 joint, it was the only way I could sleep, so it's not just for pregnant clients.
I've done a few pregnancy massage courses where it was taught side lying, very important getting the training to know where to avoid, but the side lying routines I found uncomfortable for me to do. With them face down, you just do your normal routine avoiding all the places to avoid, and it's much easier on your body than lunging and trying not to twist for side lying.
I've only had 2 clients I didn't think would fit in the bodyCushion (one was almost 8 months with twins, the other was a huge baby), and I've only had 3 people say they didn't like facedown, but the bodyCushion makes side lying much easier too, so it's fast and easy to chnage the cushions to get them comfortable side lying, so that's 5 people out of over 1000 pregnant clients that I've used the bodyCushion with.
The couches with the hole in the middle are totally another matter, they are NOT good, it's not comfortable lying over a hole when you are not pregnant so why anyone thinks lying over a hole becomes more comfortable when you are pregnant I don't understand.
There is a UK lilo with a hole, a holo, that raises the hips up a bit (which is how the bodyCushion works) Until the mother to be gets really big, that could work very well for facedown with the lilo on the couch, and it's a lot cheaper than a bodyCushion, plus retail opportunites for babymoons, the last holiday away before the baby changes life forever. (babymoon is also sometimes used for the bonding time after the baby arrives, which makes it a confusing idea) I use the bodyCushion for treatments and retail the holo.
******* added ******* I am not affiliated with any of the websites I've mentioned. Do NOT try to buy the holo from me, I'm not in UK and it will be much more expensive than buying it from the holo website directly. Both are just good products I use/recommend/suggest.