Low morphology next steps

Looking for some hope! We have a 3 year old who was conceived naturally without any problem. Been TTC for a second for 4-5 months (3 or more months having intercourse only x1 during fertile window) and husband was diagnosed with 1% morphology. Our RE said

IUI

would we 10-12% successful,

IVF

with ICSI obviously more successful. Do I right to

IVF

or should I continue to try naturally then

IUI

? Low morphology is our only issue and we have conceived naturally before. Thanks everyone!