I believe it. I work in an environment that many people would consider stress inducing; I engage in amateur combat sports; however, when my six month old loses it, I absolutely get an immediate pulse raising stress reaction.
For me, it wasn't when the kids started crying that was the most stressful, but when they wouldn't stop. You check their diapers, you check if they're hungry, you rock them gently, and even then sometimes they just wouldn't stop crying. After a while the noise would be so bad that I had to hand them off to my wife, and she did the same when she became too frustrated.
Funnily enough, it made me immune to other kids crying. Before I had kids I would get very irritated at noisy kids or crying infants in the subway. Now, I'm just happy it's not my kids and that it's someone else's problem!