It depends on the type of yoga you have been practicing.

If you have been practicing a more challenging type of yoga where it requires a lot of strength and flexibility, you will gain more muscles, due to the increase of blood flow, small blood vessels ( capillaries ) will increase. You will feel energised and you have lots of energy for the rest of the day.

If you stop practicing, your muscles will shrink and decrease in mass as your cells do not need the increased blood flow anymore.

While you stop the physical activity but eating the same amount of food, your body will store the fat. Probably you will lose weight due to the loss of muscles but you gain more fat - you may be lighter but your body shape is not as toned when you have those muscles. Please note that : as a woman, you will not be as masculine as the man, the muscles we mentioned here does not mean you were macho and less macho. Women do not have the hormone (Testosterone) to build big muscles like men.

If you have been practicing a very gentle type of yoga like yin yoga or beginner yoga, you will not see much difference in your body shape.

However you may notice you don’t feel happy, light or at peace as compared to the time you have your regular practice. Simply because you had that experience before and you started to compare. For example, you used to walk 800m home but someone started to give you a ride home in a very comfortable car with the right temperature. You enjoyed that ride for a period of time, suddenly this person is no longer giving you a ride home and you have to walk again. You start to compare the comfort you had when you had the ride with the fact that you are now walking home. You would definitely feel the difference. Same goes to yoga, during your regular yoga practice, you feel light, happy and peaceful. Once you stop, you are back to the time before you started yoga, things get in the way, stress is piling up - obviously you are not as peaceful as before.

Yoga is also the practice of breathing, when you are practicing deep breathing, your oxygen intake is 10 times more. The more oxygen you have, the more energy you have and it also activates the natural healing to your body, mind and soul. This is part of the reason you feel uneasy/ unsettled when you stop practicing deep breathing as your oxygen intake goes back to the same capacity you had before you started yoga practice.

What if I decided to come back? What will happen?
Your muscles will need time to rebuild, you may feel muscles soreness or the whole body aching due to the weakness of your muscles.

Body ache, is this bad ?
If your body ache is due to the muscles soreness result from the weak muscles. It is alright. Simply means you need time to build your muscles. You will become stronger after that.
It is advisable to take things slow, start with beginner class first.

What happens to the mind?
You will be back to that happy, light and peaceful state if you practice properly. Remember, Yoga is not a competition. If you compare, feeling bad that your fellow students who are better than you and you wanted to compete - this is not yoga anymore.
Instead you will feel even more stress.

Pay attention to every breath, focus on your movement. It is an inward practice, not a workout.