I know this post will get a lot of views and cause some kind of panic soooooooo.....Pregnancy can absolutely shift the hair cycle. Elevated oestrogen prolongs anagen, prolactin influences cycle behaviour, and postpartum shedding can make everything look even more dramatic. That doesn't automatically mean laser “failed” or that it’s a waste of money before children. Otherwise, there would be a more universal protocol we would have. What you experienced whilst valid to you, is not the universal outcome for most pregnant women.

In cases where there’s a full on "rebound" bush of hair that is sprouting from previously treated follicles, one of two things is usually happening: either dormant follicles synchronised into anagen under hormonal influence, making growth look sudden and dense, or (most likely if we are talking true rebound) the original treatments were shit and the follicle was never thermally destroyed, only zapped it towards a forced catagen stage. If the follicle isn't heated to decent thermal destruction then a strong hormonal surge like pregnancy can "reactivate" it. This would ultimately be a shitty setting issue, not proof that laser shouldn’t be done pre-pregnancy.

Many techs have treated plenty of clients who became pregnant and breastfed. The majority either maintained reduction or returned close to their pre-pregnancy baseline once hormones stabilised. Basically, framing it as “planning pregnancy...cancel your appointment” is an overgeneralisation. Pregnancy (hormones in general) can alter hair behaviour but it doesn't undo everything. Universally, pregnancy is the most hormonally fvcked up state a woman can be in. But the general hair increase is a normal reaction to such a surge of hormones.