no gender results over the phone?

Is this normal?
I had genetic testing done due to my age And thank God that it came back negative . I was asked during genetic testing if I wanted to find out the sex of the baby and I said yes. 
Well when they called with the results and after I was so thankful , I asked about the gender and the nurse said they don't give results over the phone . 
I thought it was weird but I wanted to know if any of you peeps had an answer to why ? 
I am blessed either way to have the results . 
Thank you for any insight