Caul

A caul or cowl (Latin: Caput galeatum, literally, "helmeted head") is a piece of membrane that can cover a newborn's head and face. Birth with a caul is rare, occurring in fewer than 1 in 80,000 births. The caul is harmless and is immediately removed by the physician or midwife upon delivery of the child.

The "en-caul" birth, not to be confused with the "caul" birth, occurs when the infant is born inside the entire amniotic sac. The sac balloons out at birth, with the amniotic fluid and child remaining inside the unbroken or partially broken membrane.

A child "born with the caul" has a portion of a birth membrane remaining on the head. There are two types of caul membranes, and there are four ways such cauls can appear.

The most common caul type is a piece of the thin, translucent inner lining of the amnion which breaks away and forms tightly against the head during the birthing process. "Infrequently, in past ages as now, a baby is born with a thin, translucent tissue, a fragment of the amniotic membrane, covering its head. The remnant is known as a caul." Such a caul typically clings to the head and face, but on rarer occasions drapes over the head and partly down the torso. In Germany, this would be called a "helmet" (Galea) for boys; and in Italy a "fillet" (vitta) or "shirt" (camicia). In Poland, it is called a "bonnet" (czepek), for both genders.

A less common type of caul, of unknown tissue type, is adhered to the face and head by attachment points and is looped behind the ears, making the removal process more complex. In extremely rare cases, the thicker caul encases the infant's entire body, resembling a cocoon.

The rarest caul type is a thick, soft membrane of unknown tissue type, which presumably forms against the infant's head during gestation. "Cornelius Gemma, a sixteenth century physician ... described it quaintly as being '... the remnant of another membrane, much softer than the amnion, but nevertheless more solid....'"

The caul is harmless and is immediately removed by the physician or midwife upon delivery of the child. If the membrane is of the amniotic tissue, it is removed by easily slipping it away from the child's skin. The removal of the thicker membrane is more complex. If done correctly, the attending practitioner will place a small incision in the membrane across the nostrils so that the child can breathe. The loops are then carefully un-looped from behind the ears. Then, the remainder of the caul can be either peeled back very carefully from the skin, or gently rubbed with a sheet of paper, which is then peeled away. If removed too quickly, the caul can leave wounds on the infant's flesh at the attachment points, which may leave permanent scars.

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Wikipedia