These three photos are of a baby being born in the caul (in the amniotic sac). Pure luck had me in the right place at the right time with a camera in my hand.
This is close to birth. I have photos from right as the sac began presenting until the birth of the baby. While I've seen several babies born en caul, this was the "heaviest" I've seen to date.
It is hard to see if the amniotic sac was still on the face, but from what I remember, it was. As a midwife, I was trained to pull the sac off, using a sterile gauze so you can get a good hold of it, and pull from chin to brow. One midwife who was teaching me said she watched a baby inhale the sac as the student pulled it down from brow to chin. Even if that is an urban legend, it made sense to me and didn't seem harmful, so that's how I do it and teach it.
Most doctors have never seen a baby born in the caul; the amniotic sac is ruptured routinely in the hospital (Artificial Rupture of Membranes... AROM). I heard about a doctor who wanted to see if babies could be born in the sac and challenged fellow docs to try and accomplish this. He offered a $50 bounty for every baby born with the membranes intact. Suddenly, there were plenty of babies born without AROM! I'd love to see a doctor do the same bribing now.
There are plenty of midwives who also do AROM; I do not. I have ruptured membranes twice in the last 5 years, once because mom insisted and the other for a mama who was heading to the hospital for an induction and she was already about 5-6cm dilated. Again, it was her choice and, once I AROM'd, she delivered easily three hours later.
Some reasons for believing AROM is a good idea include allowing the head to put more pressure on the cervix, helping a baby to fall deeper into the pelvis (a variation on the pressure idea) and because it speeds up labor. There are numerous studies that show that AROM only hastens labor by a mere 30-60 minutes or so. To me, not worth the risk of infection or prolapsed cord (if the baby is high).
When a mom is GBS positive, it can be an even greater reason to not AROM. Once the membranes are ruptured, many start the time clock, wanting the mom to deliver (or be in active labor) by 18 hours post-rupture. The risk of GBS infection in the baby grows when 18+ hours of time have elapsed.
Definitely, informed consent and the risk/benefit ratio must be weighed when deciding to AROM.