Fear mongering that's entirely unfounded in any real science....based on the current climate that encourages entitlement to epidural intervention. Problem is that they can't ethically do a randomized control trial to demonstrate no additional risk.
The Canadian & North American OB/GYN societies see no additional risk to pregnancy and no one had ever been refused (so my OB partner tells me). The Anaesthesiologist does the "informed choice" talk laying out the theoretical risks.
They've been saying this for a long time, but some anesthitists will do it.
"The ink in a tattoo is not in a fluid state, it has simply stained the skin, so it won't be flowing around because of a puncture. Still, you don't want skin being carried down into the spine anyway, so anesthesia equipment is designed to slice through the skin and not carry pieces down with it. "