Obstetrics

Abstract

The pre. sent review deals with a few of the significant advances in obstetrical practice and theory occurring in the year ending September 1, 1949. PREGNANCYPregnancy tests.-Based on the knowledge that the anterior pituitary hormone and chorionic gonadatropin in pregnant women's urine (1, 2) both have a spermatozoa liberating effect in the male toad, a number of pregnancy tests have been advocated using both male toads (3) and male frogs (4). Employing the male Batrachia,l Galli·Mainini (5) reports the ac· curacy of the results of this pregnancy test in 1,422 verifiable cases. In 916 instances the patient was not pregnant and negative results were obtained in all cases. In 462 cases of verified pregnancy, 458 positive results were obtained. In 623 specimens from nonpregnant subjects, men, women, and children, negative results were obtained in all instances. The rate of accuracy was thus 99.72 per cent. Forty·eight per cent of all the reactiont were positive in 1 hr. ,an additional 40 per cent within 2 hr. and the final 11 per cent within 24 hr.Using Rana pipiens, which is the common North American male frog, it has been reported by Wiltberger & Miller (4) that tests on 200 animals yielded no false negatives or false positives, provided the urine was obtained during the first trimester of pregnancy. These authors injected 5 cc. of the first morning urine in the dorsal or lateral lymph sac of the frog. Two or more frogs were used in each case, each frog was placed in a separate clean, dry, glass jar with a perforated lid and remained for 2 to 4 hr. at room temper ature. At the end of this time any urine that had been voided was examined microscopically. If spermatozoa were not present the urine was drained from the jar. The frog was then squeezed by hand while still in the jar. This pres sure usually induced another urination which was now examined. Robbins & Parker (6) performed a test in the same manner, except that they took cloacal smears from their animals beginnning 1 hr. after injection. They report the results on 122 urines, 10 of which were obtained from normal nonpregnant girls. In the remaining 112 urines there were 78 from known pregnancies, and 34 from patients with amenorrhea, who were determined t.o be nonpregnant by the Aschheim-Zondek or F � iedman tests. No false positive reactions were encountered, but there was one false negative on the urine of a patient who was only 2 weeks beyond her first missed period.In our own clinic (21) Rana pipiens has been used for preg-nancy tests in 1 Synonym for amphibia-more specific toads, tree toads, and frogs.