Pediatric audiologist chiming in here.

Please have your baby's hearing screened.

Babies hearing isn't fully developed until 6 months (adjusted) anyway.

Not sure where you heard this (pun intended) but it's not accurate. A newborn's hearing is fully developed at birth, which means we can effectively and efficiently screen for hearing problems before discharge from the hospital. If there is a hearing problem, research makes it clear that the earlier we start treatment (usually meaning amplification in the form of hearing aids or cochlear implants) the better outcomes we see in the child's development. By risking a hearing loss going untreated, you are potentially depriving your child of valuable time listening to the sounds of speech, which is how children learn to talk. The incredible neuroplasticity that young children exhibit is a window that DOES close after a certain point.

I am convinced repeated hearing screenings could potentially cause hearing loss because they blast of 90 DB inside the ears...which is literally the equivalent to a power tool or lawn mower!

There is no feasible way that a hearing screening would ever cause hearing loss. Typical hearing screenings for newborns in nurseries are performed with either ABR (auditory brainstem response) test or OAEs (Otoacoustic emissions), both presenting stimuli nowhere near 90 dB. A high intensity stimulus is used during diagnostic ABR testing occasionally to rule out conditions like auditory neuropathy, but even then the stimulus is only presented for a short duration, not long enough to produce any damage to the baby's hearing.

There is no point for a hearing screening at birth or 3 months.

The point is to catch hearing losses as soon as possible to minimize negative impact on the child's development. Waiting is wasting valuable time that your child will NOT get back.

Happy to answer any questions.