Okay, this is a little involved, but this is the response I got . If I've not relayed it well, query it and I'll try and explain better.
First, she stresses she's not a medical professional so not qualified to give medical advice.
She doesn't know anything about the mercury side of things, so you'd need to look further into that, if that worries you.
Studies suggest that it is safe in pregnancy.
I'll copy/paste the next bit: "This is the first year that "Fujian" will be in the vaccine for the North hemisphere. Yes, this is considered to be a non-contraversial year by the experts, there is NO sign of anything out of the ordinary, and my info is up to date as of 2 weeks ago. This is as confident as we can be of a good match.
The Fujian component of the vaccine has been used in the southern hemisphere during their winter (our summer) so it has been well and truly tested!
But.. vaccines always have risks, and these need to be balanced against the risk of non-vaccination. If as a pregnant asthmatic she is hit by a full bout of flu, that is potentially problematic.
One additional point.. ask her if she thinks she had flu last year. If she did, then this years vaccine may not add anything. If she didn't, she should think about it seriously as Fujian hadn't circulated before last winter, so she would most likely be susceptible.
I would trust the CDC info:
Who Should Get "
She also said she will be getting vaccinated this year.
Hope this extra info helps.