"Unfortunately Judith Rooks started this whole effort right at the time, unbenownst to all of us, that the company that made the only equipment for this purpose decided to stop making it," Bishop explained. "So we've had a big disconnect between interest and ability to institute it due to lack of equipment."
Starr's group at Vanderbilt had to resort to the secondary market for pre-owned machines.
That limitation may change any called time, according to Evan McAllister, CRT, whose company Nitrogesia in Double Oak, Texas, is awaiting the all clear from the FDA to put their nitrous oxide equipment on the market.
"Medical research-wise, equipment-wise, we're ready to go," he told MedPage Today. "We were ready to go a month ago."
He predicted that it would be available for the waiting list of universities and other centers within a month.
The equipment and gas are relatively cheap, and aren't likely to generate a lot of money for either hospitals or industry, Serat noted.
"It's a labor of love, it really is," agreed McAllister.
Another possible hang up is concern over safety.
No investigation has been looked into the effects of in utero exposure to nitrous oxide, and nitrous oxide exposure to allied health professionals often exceeds federal occupational safety limits, Palmer cautioned.
Those occupational safety levels were set arbitrarily based on weak data from operating rooms in the 1970s and prior suggested a possible effect on time to get pregnant, Serat argued.
The professional exposure concerns can be addressed by use of masks that scavenge the nitrous oxide and periodically having nurses wear badges to monitor exposure, Bishop suggested.
But since even the efficacy data for pain relief with nitrous oxide is uniformly old, Starr said her group plans to study these issues once clinical use gets underway at Vanderbilt.
Dartmouth may wait to make its final decision on instituting nitrous oxide in the labor ward until they see Vanderbilt's data and have more safety reassurance in hand, Serat noted.
But that would be a mistake, Rooks argued, noting it will be years before that data comes in whereas the European experience shows millions of women having used it without any evidence of problems.
"Just because people have been using it doesn't mean we know enough about its safety," Palmer countered.
It took a long time for epidurals to be accepted as safe, too, noted Rooks.
"Like anything it will come slowly," she predicted.
That grassroots growth is being helped along by women like Jaeger, who has been spreading the word among her pregnant friends.
"I think it's crazy that more hospitals don't use nitrous," she said.