Thanks for the chance to help. I am an attorney with over 12 years military law
I am sorry to have to bear bad news. The fact that AFI 36-3208 does not break out different rules for different career fields will not help you. In fact, it would tend to not be helpful at all.
To get that bonus you had to agree to not request to be discharged early.
AFI 36-3208 is clear that an airman who is pregnant can request to be separated. So you can make the request.
But AFI 36-3208 also makes clear that the request must be process through your chain of command. If your commander recommends denial of the request, then the request is forwarded to AFPC for adjudication.
The problem you face is that by taking the bonus money, and obligating yourself to the contract length, you give the AF a basis to deny your request to separate based on pregnancy.
They can still separate you...no harm in asking.
Just understand that your case will be evaluated in a different light than an airman who did not take a bonus to remain in.
Again, sorry to have to bear bad news