Thanks for the query.
There is very less possibility of pregnancy
in your case.
In diabetes hormonal
imbalance can be seen that can lead to menstrual irregularity.
So try to keep your sugar levels under control and maintain ideal weight for the height.
Consult gynecologist once get examined and check for thyroid levels once.
With her advice you can take tablets for withdrawal bleeding and for constipation
For more details you can ask me through: http://www.healthcaremagic.com/doctors/dr-sree-gouri-sr/63429