That is just obnoxious! It is YOUR baby and YOUR birth. No one else has any claim to it and it is none of their business under what conditions you give birth.
Birth is about the baby AND the mother. The mother is not just a container for making a baby -- she is also going through a transformative experience. And like previous posters have said, what affects the mother affects the baby. Further, birth is an intimate experience just like conception. Your body will function properly, hormonally speaking, only if *you're* comfortable, just like when you're having sex. And that goes for postpartum too, when the hormones are still making changes in your body.
I am very sensitive to the energy of people around me, and prone to PPD, so we took it slow. NO ONE was invited to witness the birth, and we had very few visitors afterwards -- about 12 hours after the birth my MIL (who I love) stopped by for a few minutes
to bring food and take my other children back to her house, and she knew better than to ask to hold the baby.
My FIL stopped by for a few minutes about five days after the birth, and my mom and dad didn't see the baby until she was two weeks old. Most of our other friends and family didn't see the baby until she was several weeks old. It wasn't personal. We just didn't want anything to interfere with my recovery and with our bonding with the baby, so we only brought others into it slowly.