@bakersh3 Hi, I'm a certified prenatal yoga teacher. I have some thoughts and some suggestions.
Bc yoga is philosophy driven, as well as physiologically motivated, some of the things we do or do not do in prenatal yoga are for philosophical reasons. These have to do with cultivating the right type of energy, according to yogic thought, for a spiritually and physically healthy pregnancy. Physiologically, we're worried about incorrect core engagement in e.g. Plank, over-taxing shoulders in e.g. Chaturanga, and generally about the possibility of students leaning too much into relaxin-induced flexibility and coming out of their pregnancy with a new chronic injury.
If you want to have a more dynamic, "yang" yoga practice, and especially if you want to participate in "regular" yoga classes, you need to really have a very, very good understanding of your own body and of how to safely modify. You need to do more than just make space for your belly!
it is also helpful to learn a little about yogic philosophy so that you can decide which philosophical recommendations do and do not work for you. Especially if your goal is to prepare for birth, a yang practice might not get you where you really need to go. You might do better with a yin-inspired hatha practice that has you holding asanas and engaging your breath mindfully for longer periods of stillness (think relaxing your face while strongly engaging you legs and breathing mindfully - - > like the ideal way to cope with a contraction).
If you want to do a yang practice anyway, you need to have the discipline to stop at e.g. Your pre-pregnancy flexibility, maybe plus 5%. Be conservative. Be very aware of what your body is telling you and back off early. Use a million props. Get a headstand bench and put it at the top of you mat, do plank, chaturanga, downdog (your whole vinyasa or sun salute) with your hands on the headstand bench (the incline will help protect your core and your hamstrings). Be aware that your pelvis has 3 joints that are all loosening up and that you do
not want to stretch them (stretch your pelvic floor,
not your SI joint!!!) . Let your hips
always fold naturally. Be aware that there are a number of common cues in regular yoga classes that are unsafe in pregnancy.
The problem is that there are a lot of little things that you need to be aware of to stay safe , and lots of possibilities for modifications for prenatal yoga. To keep everyone safe, many classes revert to a lowest common denominator. A really good prenatal class will give you 2, 3, or more options and alternatives.
I'd like to explicitly warn you against trying to do hot yoga as some commenters have suggested. This is wildly dangerous for 2 reasons. 1) it increases your core temperature the same as having a fever, getting in a sauna, or taking a too hot bath for 60+ minutes. This is dangerous for unborn babies. 2) the heat increases your flexibility, which on top of relaxin, sets you up to go too deep into poses and hurt yourself, e.g. Stretch your knee ligaments and come out with a lasting knee injury or a hamstring injury. Healing postpartum is hard enough without an extra yoga injury.
For tearing, honestly you should be doing mostly breath work (three part breath, diaphragmic breathing) . Consider trying the Epi-no so you can practice relaxing your pelvic floor when baby starts to crown.
Be careful and have fun!
