The main finding from these case reports and the literature research is that meconium is not always black-greenish. The newborn’s colon contents can also be golden yellow. This might happen without feeding and / or longer survival time and look like typical breast milk feces. It is rare, but it does happen [1, 2]!.

Intensive literature research, particularly in the older German forensic literature, showed that the knowledge of the possibility of the yellow color of the meconium was quite widespread in the 19th and 20th century. Nonetheless, this finding was never used to draw any conclusion about the child’s possible survival time or food intake / nutrition. The various sources in the German forensic literature of the last nearly 200 years are summarized in Table 1 [3,4,5,6,7,8,9,10,11,12,13,14,15,16,17]. No comparable description of yellow meconium could be found in the English forensic literature of the 20th and 21st century; reviewed English references are provided as Electronic Supplemental Material (ESM). In many English books the term “meconium” does not even appear in the index, or at most “meconium aspiration”, “meconium staining”, or “meconium aspiration syndrome”.

The rare occurrence of yellow meconium plausibly explains why this finding has fallen into oblivion - it was simply no longer reported due to its low frequency itself and declining number of neonatal autopsies. Compared to today, forensic pathologists in the second half of the 19th and first half of the 20th century encountered a relatively high number of neonatal autopsies. At the end of the 19th resp. the beginning of the 20th century, newborns made up 20% of all forensic autopsies [15].

A reason for the deviating color up to the very impressive golden yellow color of the meconium could not be identified with certainty. In 1931, Georg Strassmann was the first to assume a connection between yellow meconium and putrefaction [16]. He reported a total of 6 cases of exhumed newborns, all of which he examined within one year (1929). In two of these cases he described conspicuously yellowish infant saliva, in one case yellow-green saliva. The corpses were buried without a coffin between 16 days and 4.5 months, leading to a wide range of putrefaction and weakening the correlation between yellow meconium and decay. G. Strassmann also described histological findings of the yellow meconium: It contained normal components of the child’s saliva, but the meconium bodies were conspicuously pale, colorless and with the dye leaking from them in the surrounding area. From this, he concluded the connection with putrefaction. This was not questioned until 1986 - the last source before the current ‘rediscovery’ of this finding - without any further concrete reference or other evidence in favor of this hypothesis [3].

Many of the historical references cited describe that the yellow meconium was mainly observed in the upper parts of the large intestine. This differentiation is only lost in the literature with G. Strassmann, after whom he considered the connection with putrefaction to be possible. Analogous to the historical references, it may also be considered a rule that the fecal matter is often only dark green in the lower sections of the large intestine and yellowish-brown in the upper Sect. [14].

The black-greenish color of the meconium is due to the bile pigments, especially biliverdin as an intermediate product of haem degradation. However, it seems obvious and understandable that the deviating (light) yellow or golden yellow color of the meconium is caused by a reduced proportion of bile pigments, maybe associated with a (temporary? ) reduction in the patency of the newborn’s bile ducts - for whatever reason. A connection with the content of bile pigments also seems plausible. Unfortunately, in the cases described here, the bile ducts were not explicitly described (in the first case due to putrefaction).

Social circumstances and developments can have a considerable influence on forensic autopsy routine. The declining number of autopsies of newborns is undoubtly absolute positive but must not lead to the loss of previously widely available empirical knowledge - and to incorrect assessments.