Yes, they can. They were given to a female gorilla named Johari at Toledo Zoo both during the pregnancy and rearing of her daughter (with no side effects). Her daughter now lives at the Como Zoo and has a daughter of her own. There’s an interesting article about it here: The Blade | Toledo's breaking news, sports, and entertainment watchdog
I've always been interested in the motivations for hair plucking in gorillas. We know its obviously stress related, though some individuals may copy others too. I've known some gorillas, particularly handraised ones, do it all their lives. Others seem to start and stop (or at least much reduce) depending on changing influences.
Interestingly, at the Calgary Zoo, their females have been some of the worst pluckers I've ever seen. Every single one of their females (numbering 5-6 for the past 10+ years) plucked to some degree, with only one maintaining the majority of her hair, and at least two plucking so bad they were almost entirely naked. Their original silverback passed away in 2016, and between then and late 2019, the troop was without any males. During this time, some of the pluckers did reduce the degree of plucking, but not by any tremendous amount. The big difference started in September of 2019. This was when their new silverback, a very easy going younger male, was introduced. Far forward to 2021, and some of their females are virtually unrecognizable, in the best way! All of the females have noticeably reduced plucking, to the point where only one still has noticeable bald patches (their worst plucker, I wouldn't be surprised if she has some degree of follicle damage and will never fully hair out again. But even she has a noticeable amount of more hair). All the other females are now fully coated, and look like new individuals! So in this situation, the main factor apparently was the male presiding over the troop.
I've seen a rather similar situation in the UK, where a female who had never plucked herself, suddenly started just after the silverback died. It stopped again when they got a new one. The stress of being without a leader seemed the causal factor there. At Paira Daiza in Belgium they had a male (Wazungu) living in a male group with two others only slightly younger than him. He seemed to pluck himself mildly, until he recently moved to another male group in France where he is by far the oldest, with much younger males. His coat is so much better now.
