Probably referring to the idea of having children becoming more "trendy" amongst young people ... whereas previously having a baby was seen as not "cool," i.e.

Probably referring to the idea of having children becoming more "trendy" amongst young people ... whereas previously having a baby was seen as not "cool," i.e. something boring people settle down and do, some "trendsetters / influencers / celebrities" have been having kids and making it seem desirable. I need a shower after writing this post.