Presence of Oxytocic Substances in Urine During Labor.

Abstract

Sincer substances of great biological significance are excreted in the urine during pregnancy, it seems possible that other substances of different biological action might be excreted during active labor. Guerin-Valmale, Loriot, and Verdeuil claimed that labor urine produced contractions of the human uterus in vivo. They were able to induce labor in 2 patients 10 days before term by administering labor urine by proctolysis; the patients were delivered about 12 hours after the instillation. Barjaktarovic used the same method in 10 cases during different months of pregnancy and concluded that to induce labor in the second half of pregnancy amounts up to 4,000 gm. of labor urine were necessary. We have, therefore, attempted to extract oxytocic substances from labor urine. Urine was collected from women during active labor and combined until a total volume of 10 or 12 liters was obtained. (Pituitrin was not given to any case.) Thirteen such collections were made, and each was worked up separately. The samples were acidified with acetic acid and concentrated in vacuo at a temperature of 30-40°C. The method then used to obtain the oxytocic substance was that described by Kamm and his co-workers for isolation of the active principles of the posterior lobe of the pituitary gland. The final product was a crude material of a gummy character and colored with urinary pigments, 10 liters of labor urine yielding an average of 0.5 gm. This dried material was taken up in distilled water and dialyzed over night in a refrigerator in a parchment bag. The solution from the bag was then made neutral to litmus with sodium carbonate. The solution was tested, using about 0.4 cc. from a total volume of 25 cc. representing the original 0.5 gm., on human uterine muscle obtained from Caesarian sections at term.