Hello. Welcome to ask the doctor.
I have read your query.
I understand your concern.
Absent eyebrows since birth may be due to various reasons like
1) atrichia -where there is absence of hair since birth
2) Syndromes- it may be a part of syndromes like Ectodermal dysplasia where there is other associated symptoms and signs like absent teeth, less or absence of sweating, sparse hair on scalp etc.
3)Autoimmune - it may be due to formation of antibodies against normal structures of our body like hair follicle in such case.
I will advise you to get your thyroid profile done.
Visit your doctor so that he can examine you and order tests for you.
You can share my opinion with him.
I hope it helps.
These Q&A’s are for educational purposes and should not be relied upon as a substitute for medical advice you may receive from your physician. If you have a medical emergency, please call 911. These answers do not constitute or initiate a patient/doctor relationship.