In the beginning you sacrifice everything, including your basic needs, like showers and decent meals. If you go into it feeling like you have a spiritual grasp on who you are in the big picture, that will soon fade as your life becomes focused on first chakra, survival issues. You might even have a moment somewhere down the road where you pull your head out of the shitty diapers and barf rags and lament the loss of your spirituality. If you get a moment.
Sure, as the years progress, you get more time to yourself and you can pursue your dreams and desires again, but that tether is so strong, you may find that you cannot be totally present with your own freedom. You may be taking a relaxing bath and find you can't completely relax because you're missing your child or you're wondering how they're doing or maybe you even feel guilty for taking time away from them. Motherhood is wrought with land mines like guilt and shame and ancient threads of unworthiness passed down through your maternal lineage.
On the flip side though, those land mines are powerful opportunities to heal yourself and your lineage, to break the dysfunctional chains of your families. If you can stay afloat for the first several years and avoid sinking in the guilty diapers and snotty shame, you will come to a point where your commitment to your child and your own healing will begin to sprout wings. As you forgive yourself for the dysfunctional patterns you learned from your own mother and rekindle your connection to Spirit, with your child, those wings will grow and, together, you can fly free of the cage that many mothers come to secretly and shamefully resent.