4 month baby Vagina health

My baby girl is 4 months old now, up recently I have noticed her labia wrinkling and it has remained so. I am worried if I caused this by not changing diaper at night from 8pm- 6am since she started sleeping through the night. She comes for constant feeding in her sleep but wakes up fully at 6. If I attempt a diaper change in night she immediately wakes up and refuses to go back to sleep. Her diaper is sufficiently full by morning. My concern is if the moisture inside the diaper caused that wrinkles?