I don't see a problem with a woman being offered this test, as it does pick up on carbon monoxide leaks in the house as well.
But forcing it?
I struggled to quit smoking entirely while pg, I had the odd one. I knew it was terrible, I'd cut down from being a regular smoking when my unexpected pg happened, but I had a very difficult pg for many reasons and I occasionally struggled and had a cigarette. It is nothing to be proud of and I wish I hadn't done it, but I did.
If I had had this test done at the booking in appt it would have come back as positive, as I found out quite late I was pg and, as it was unexpected, it took a few weeks to cut down and quit. If I had had this test done later it could potentially have come back as positive.
But none of that would have actually achieved anything. I was scared enough and hated myself enough for struggling to completely quit, knowing that I might get 'caught' (yes, as if I was a teenager nicking sweets from a shop) would have made me even more stressed and would have probably damaged my relationship with my mw. As it was I generally had supportive mw's who didn't judge and who helped through each relapse.
Women who are struggling to quit smoking during pg need support, just like anyone struggling to quit any addictive substance. For many women pg is a hormal, emotional, even scary time and feeling bullied by HCP's is not going to help one iota. They need someone who will ask what can be done to help; they don't need judging. I do understand why people judge women who don't manage to quit while pg, but if you honestly think that attitude will actually help anyone, that is extremely blinkered.
There are many other tests, as mentioned above, for problems which are completely unseen during pg. Spend the money on that. Support women in pg, stop telling them what to do.