Please don't worry or take stress, everything will be fine, trust in God. Lice is just a common thing that can happen to anyone, it won't affect your sweet baby. Just stay positive, do simple wet combing with a little camphor or neem oil, and take good care of yourself.
Actually, I got lice from my niece during my 5th month and was so scared to use chemical treatments. Personally, I just used a lot of coconut oil, wet the hair, and used a fine-toothed nit comb (ju-kanghi) daily to remove them physically. It took a few days but it worked perfectly and I didn't have to use any chemical medicines.
Oh dear, I totally understand how stressful any extra issue can feel right now, especially when we are trying so hard to protect the baby. Lice is just a normal infection from close contact, nothing to do with pregnancy itself. Please don't use any harsh chemical shampoos from the pharmacy without asking your IVF doctor first, stay strong.
I had to deal with this while breastfeeding my little one and it's so annoying! I washed my hair with warm neem water and spent hours doing the wet comb method with a good conditioner. It's safe, chemical-free, and doesn't affect the baby or milk at all, so maybe try that.
Dealing with PCOS made me super cautious about what chemicals I put on my skin and hair, especially during pregnancy. Lice usually just spreads from someone else in the house, it's not internal. I would suggest asking your gynac about safe options first, rather than trying random strong anti-lice shampoos from the market.