Ivf/pgt m

Hey , i need advice . Im 35 years and my hubby is 34 years . He has a rare condition which we have 50 chances of passing to the child. We didn’t know it so we tried having a child natural and at 16 weeks we had missed abortion . Later that year we found out of this condition then we went for ivf .

First cycle of ivf failed Afc 13 , follicles seen during stimulation 10 , egg retrieval 8 , mature 6 then only 1 made it to day 5 blast and went to test . Just got the results that its affected .

Now our option is to try round 2 but what to ask if any one can help what should we do to improve our fertilisation rate and has anyone faced this its so hard and im just so down ! Can genetic in sperm be improved ?? Help . Thank you