I'm not sure Juliet is implicated so much as associated. If what we've heard so far is true, she attended the fatal pregnancies, but did not cause the fatalities. She may well have had a hand in some of the conceptions, in which case should could arguably bear some responsibility for the deaths, but I'm not altogether sure that's clear...
If I'm recalling "One of Us" correctly, she came to the island after being told that the women there couldn't get pregnant - and, indeed, her work pre-island was in fertility and conception, not in obstetrics; she's good at getting women pregnant, not getting the pregnancies to come to term. I suspect that women who have been on the island for a long time have trouble getting pregnant, period - Sun got pregnant after only five weeks there, but I got the impression that women who had been there for longer had a hard time getting pregnant at all. I definitely got the impression that she has had a hand in all the conceptions. If that's the case, she bears a great deal of responsibility for every death after Sabine's (when she figured out what was going wrong) - which was after she'd been on the island less than six months. She could've refused to help Ben (who never gave her any reason to believe that he'd helped her sister, just an evidence-free and none too credible promise) - he probably would've harmed or killed her, but eight more deaths is the point at which it's "sucks for her." (She's taken the Hippocratic Oath; the fact that [Ben says] the women consented to get pregnant is irrelevant.)
Anyway, that's just my $0.02 on part of why I got seriously evil vibes from Juliet last episode.
I would hope in that case she would say something about needing to confer w/him as her medical doctor. I'm not saying Jack wasn't rude, cause he was, but I wouldn't disclose anything in front of Juliet.
I blame both Kate and Jack in this scene. Kate shouldn't have told Jack, period (if she wasn't sure she could keep a secret, she shouldn't have promised Sayid), and she compounded it exponentially by telling Juliet as well, given that even she doesn't trust the woman. As for Jack... CompetentDoctor!Jack of S1 or S2 would've handled it better, I think; I am very much of the opinion that he was a good leader for quite a while, but has fallen apart under the strain. Anybody who's ever so much as had a part-time clerical job in a hospital could instantly tell you, "He's accepted the role as island doctor. Someone asks for a confidential conversation, he STFUs and complies, no delays or questions acceptable." Medically warranted consults with other physicians only (and if someone just asks to talk to a particular doctor in private about something unspecified, not have a procedure, it's not warranted). No ifs, ands, buts, or exceptions. I don't expect TV medical practice to mirror the RL perfectly, but we've seen Jack respect confidentiality with Charlie, Sun, and Hurley before. It's been established as part of the character's routine, so I think it's significant that he's deviating from it now. If he can't remember his first-year undergraduate pre-med classes... let's just say I'm kind of shuddering to think what he and Juliet are planning.