Morning breath has nothing to do with pregnancy. Bad breath and pregnancy are two varying terms. When bad breath is caused by certain actions and inaction of individuals whether consciously or unconsciously, pregnancy is totally different. That a woman has bad breath does not make her pregnant.
Most pregnant woman conceives and give birth without even experiencing bad breath. While others due the nausea may lead to morning breath or bad breath. This is due to individual difference; often what most people experience, there are always a few who may not experience such. That is how the human body was created to be. The human body responds to certain changes and uses symptoms to identify inconveniences. For example, one may feel symptoms such as headache and bitter mouth, one can however, self-diagnose the feeling to be symptoms of malaria. So the body has inbuilt mechanism to detect what is wrong given some symptoms.
Individuals who have cancer usually have bad breath which indicates signs of cancer. This bad breath may be due to the drugs they consume. Some drugs which individuals take tends to dry the saliva, thereby leading to bad breath. People with diabetes also experience bad breath, this is due to the fact that diabetes usually leads to periodontitis. Periodontitis is a disease that affects the gum. It is also called gum disease. Affected tooth Gum may somehow lead to bad breath. Check previous post.
Bad breath is not a sign of pregnancy, but the symptom of pregnancy which is nausea may lead to bad breath.
How to manage bad breath from pregnancy
Managing bad breath from pregnancy is quiet easy.
 Avoid taking drugs that are not recommended by the doctor. Most drugs are not suitable for pregnant woman. Due to the heavy reactions women face during pregnancy, they may be prompted to take in drugs; which may affect their health conditions. Like I explained before, some drugs affect the saliva, shortening and drying it, leaving the mouth with a foul smelling odor.
 Using recommended tooth paste is another way of managing bad breath during pregnancy. Pregnancy is a delicate period; women should be careful what they consume. Some tooth paste may help with the obnoxious feeling during pregnancy.
 Visit the dentist when having issues with the mouth or the teeth.
 When experiencing nausea, use mint and chewing gum to keeping your system normal. Mint contains menthol; a substance that is not harmful to the human systems: and helps keep the breath fresh at all times.