Not at all! Yoga can be adapted to young children, since they are in a phase of learning, discovering and expanding. They usually are very flexible too. Yoga for children is very different from yoga for adults and some teachers are experts in this kind of work.
Yoga for adults is different. It aims to keep the practitioners in good health. The poses usually are less intense, they are accompanied by deep breaths, perhaps with rhythms. It is common to finish the yoga practices with an exercise of breath control.
There is no upper limit in the age to practice yoga. In theory practices for less young people will be more turned to meditation. But that is not always the case. It depends a lot on the students and their objectives.
Some older students enjoy practices that are more physical and that is ok! The point is always to find a good teacher who can suggest interesting exercises without risks. I worked a lot with 70 to 85 year old people and I enjoyed it very much! They taught me a lot!
If you have a health condition, the first thing to do is to ask your doctor if you can practice yoga! It is good to tell your doctor who you think is going to be your teacher and eventually put them in contact, so that your doctor can evaluate the risks of that kind of practice.
There are many yoga teachers and yoga therapists. There are also many different ways of practicing and of teaching yoga.
If you are not in good shape, you have to be careful choosing your teacher. Make sure you tell your teacher all your health issues and listen to what the teacher has to say. You will be better in the hands of a yoga-therapist than of a yoga-teacher. it is also more convenient to choose individual lessons, or try to find a group where everyone has the same kind of restrictions.
Of course! But be sure your teacher knows how to deal with pregnant women. There are many exercises that will be very good for your pregnancy and others that must be avoided. So, choose individual classes, or a group only with pregnant women.
Along pregnancy your ability to perform certain exercises will change and what is desirable in the first three months, the second or third three months is different. Ask your teacher about this and check it with your doctor! The way you are living your pregnancy is very relevant in the choice of the exercises you can do!
However, well directed yoga practices will increase your joy of being pregnant, will deepen your relation with your baby and may ease the moments of delivery!