20. Yellow/green blood. The Shulchan Aruch paskens that if an infant is yellow/green, it is a sign that “not all his blood has entered him” [“לא נפל בו דמו ”], and he does not get a bris until all his blood enters him and his appearance is restored to the appearance of other babies (שו''ע סי' רס''ג ס''א ). Most poskim agree a bris can be performed as soon as his blood is like other babies’ blood (תמים דעים להראב''ד סי' קע''א, חכ''א כלל קמ''ט ד', שו''ת שבט הלוי ח''ג סי' קמ''ב, ברית אבות פ''ט כ''ו ) unless the jaundice is substantial and the bilirubin levels are high, in which case sometimes the infant must wait seven more days, as will be explained below.
21. Medical background. Most babies [60%] display signs of neonatal jaundice in the days following birth. In most cases of babies born at full term with jaundice appearing only after 24 hours post-birth, it is physiological jaundice caused by immaturity of the infant’s liver. This results in elevated bilirubin—a yellow pigment in the blood—and gives a yellow appearance to the infant’s skin. It is not considered a disease; it takes time for every infant’s liver to mature and function normally [it is not a pathological jaundice caused by a virus or bacteria, which is considered illness of the whole body].
22. However, a high level of bilirubin in the blood can be dangerous to the infant. Doctors establish that a bilirubin level of 12 mg/dL is normal for an infant’s first week of life and is not considered an illness at all. If it is between 12 and 15 mg/dL, doctors instruct to monitor the infant with recurring blood tests to ensure it is not rising more, but they do not treat it, as it usually goes down on its own. If it is 15 or 16 mg/dL and up, they treat it with blue light therapy to lower the level of bilirubin until the numbers stay down on their own without the aid of light.
23. Bris. The poskim discuss whether the jaundice found in most infants is the “yellow/green illness of not having all the blood” mentioned in the Gemara and Shulchan Aruch. It is likely that the case of the Gemara and Shulchan Aruch is a rare occurrence, not something found in most infants, in which case only if the infant is exceedingly yellow, in the words of the Rambam, there is concern it is indeed an illness; or perhaps it is actually the illness Chazal discuss, and one must be careful even if the infant is just slightly yellow.
24. In practice. Thus, in practice, rabbanim and mohelim take two things into account: 1) the general appearance of the infant’s degree of yellowness to the mohel’s eye based on his mesora on this issue, and 2) the infant’s bilirubin numbers. With the two factors together, a decision is made as to when to perform the bris.
25. It is accepted by nearly all mohelim today in Eretz Yisroel that a bris can be performed if the infant’s bilirubin is 12 mg/dL or below, as from a medical standpoint, there is no problem at all, and they do not even monitor it. The mesora I got from my rebbeim is that if it is under 14 mg/dL and going downward, a bris can be done, as doctors do not even treat it until it is 15 mg/dL (מו''ר הג''ר מאיר בראנדסדארפער ).
26. Some hold that if the bilirubin level reaches 18 mg/dL, it is considered an illness of the whole body and they must wait seven full days after the level goes under 12 mg/dL. However, my mesora is that even if it reaches 18 mg/dL, there is no need to wait seven days after recovery. Only if additional treatment, e.g., blood transfusion, was needed or the bilirubin reached an abnormally high number, e.g., above 22 mg/dL did my rebbi instruct them to wait seven days after recovery (הג''מ בראנדסדארפער ).
