PRIZE ESSAY. PRIZE ESSAY. ON THE CORPUS LUTEUM MENSTRUATION AND PREGNANCY. y BY JNO. C. [DALTON, Jr., M. D. Extracted from the Transactions of the American Medical Association. PHILADELPHIA: T. K. AND P. G. COLLINS, PRINTERS. 1851. o r.. X ' ' 851 1 C-L ON THE CORPUS LUTEUM OF MENSTRUATION AND PREGNANCY. INTRODUCTION. There exists among medical writers at the present day a very confused idea with regard to the corpus luteum. Notwithstanding the endless controversies that have been carried on respecting its origin, growth, and structure, there is still a great diversity of opinion on all these points, even among those who have personally devoted their attention to the matter ; and for the general reader it would certainly be impossible, from the various accounts which have been published, to arrive at any satisfactory conclusion. These contradictory opinions prevailed not only in the earlier epochs, when Haller* denied positively that corpora lutea were ever to be found in virgin females, and when Meckelf considered them as glandular structures, destined to secrete a sort of "fluide generateur," or female semen ; but even at the present day, when so much addi- tional light has been thrown on the whole history of generation, a similar diversity exists ; and the corpus luteum is now described by different authors as a development of the outer and of the inner membrane of the Graafian vesicle, as a deposit between the two membranes, and as a growth external to both. Perhaps the most debatable question of all relates to its connection with conception and pregnancy. At an earlier period, this was simply a question whether corpora lutea ever existed in the ovaries, except as a con- sequence of impregnation : some writers, with Haller, denying the * First Lines of Physiology, Am. ed., 1803, p. 430. ■j- Manuel d'Anatomie, vol. jii. p. 730. b PRIZE ESSAY. possibility of such an occurrence, while others asserted that they had frequently observed them in virgin animals and unmarried women. In later times, however, it became a question of the pos- sibility of establishing a distinction between true and/a?sg corpora lutea; i. e., those which resulted from impregnation, and those which owed their origin to some other cause. Notwithstanding these differences, however, it has been always reducible to a single very interesting and important inquiry, viz., whether, from the ex- istence of a " corpus luteum" in the ovary, it can with certainty be inferred that impregnation has taken place. Among those who considered the corpus luteum as necessarily connected with impregnation, many, like Haller and Meckel, had no conception of the spontaneous discharge of ova during the season of heat in the lower animals, and at the period of menstrua- tion in the human female ; a process which has recently been more or less generally recognized as a regular and natural function. Consequently, they regarded the corpus luteum as only resulting from sexual intercourse, or, at least, from some extraordinary ex- citement of the generative system. William Hunter, in his plates of the human gravid uterus, gives drawings of the corpus luteum as an acknowledged and indubitable accompaniment of pregnancy alone. John Haighton,* in a paper on this subject in the Philosophical Transactions, comes to the following conclusion: "I may then say that no corpora lutea exist in virgin animals ; and that, whenever they are found, they furnish incontestable proofs that impregnation either does exist, or has preceded." He does not, therefore, recog- nize any distinction between corpora lutea, nor the possibility of any discharge of ova independent of sexual intercourse. He uncon- sciously, however, himself furnishes evidence that such discharge may take place, in his various experiments in which the oviducts were divided before and after coition ; corpora lutea being found in the ovaries in both instances. "We should expect,'' he says, " in the one case to find the full effects of impregnation, and in the other no traces of it would be seen. Instead of which, the procreative actions (formation of corpora lutea) are no further advanced where there has been an opportunity for the passage of the semen, than in those cases where its passage has been impossible." He attempts to explain this apparent contradiction by supposing that the ovary » Phil. Trans., 1797, p. 114 INTRODUCTION. 7 is excited to the expulsion of the ovum by " consent of parts;" the stimuhis of the seminal fluid in the uterus being sufficient to cause the rupture of a Graafian vesicle, although its passage to the ovary- has been interrupted. It apparently does not occur to him that the assumed connection betvreen the corpus liiteum and a preceding coition is entirely without proof; and that, without this assumption, there would have been no discrepancy in the appearances which he is at so much pains to reconcile. Cruikshank* also relates an instance, in the human subject, in which the rupture of a Graafian vesicle was not improbably quite independent of coitus, without in the least suspecting the true nature of the case. " I also have," he says, "in my possession the uterus and ovaries of a young woman who died with the menses upon her; the external membranes of the ovaria are burst at one place ; whence, I suspect, an ovum escaped, descended through the tubes to the uterus, and was washed ofi" by the menstrual blood." The writer, however, as may be gathered from the context, evidently supposes that the escape of this ovum was in consequence of coitus ; since, throughout his paper, he considers the occurrence of a corpus luteum as direct proof of impregnation. Velpeauf speaks of the corpus luteum as a growth taking place "after coition," without alluding to the possibility of its formation under any other circumstances. Montgomery! takes much the same view of the matter. He speaks of the maturation and discharge of an ovum, and the accom- panying growth of a corpus luteum as taking place "on the occur- rence of conception;" and, though he acknowledges that bodies resembling corpora lutea may be produced in the ovary by other causes, yet the true corpus luteum, resulting from impregnation, may, according to him, be always distinguished from them. "Such," he says (p. 240), "is the result of my own observations on a very large number of bodies, both of women and animals ; and in no one in- stance did I ever find a true corpus luteum, except as the product of conception." He gives some marks by which the true corpora lutea are to be distinguished from the false, but his description, in this respect, must be regarded as somewhat imperfect. The yellow matter of the corpus luteum he considers to be surrounded by the outer membrane of the Graafian vesicle, while its cavity is lined by the inner, it being enclosed between the two. • Phil. Trans., 1797, p. 135. f Treatise on Midwifery, Meigs" ed., Philad., 1831. J W. F. Montgomery, Signs and Symptoms of Pregnancy, London 1837. 8 PRIZE ESSAY. Dr. Gross* recognizes the occasional existence of false corpora lutea, which, he says, may be produced without coitus, in conse- quence of "strong sexual excitement." He concludes, however, principally following in the track of Montgomery, that the true cor- pus luteum is good evidence of pregnancy. Dr. Edward J. Seymour,! though he acknowledges that corpora lutea occasionally exist without impregnation, inclines to the opinion that, as a general rule, they are good evidence of its having taken place. "From these premises, comparisons, and observations," he says (p. 32), "my opinion has been formed that corpora lutea are the result of the change which takes place in the ovarium by the bursting and discharge of the ovum — occurring rarely in virgin ani- mals, because the bursting of an ovum is not a frequent but only a possible occurrence, but always following impregnation, and dimin- ishing as gestation proceeds." Dr. Blundell| expresses himself on this point with great reserve. He thinks that, in some of the lower animals, a corpus luteum, " not to be distinguished from that of impregnation," may be produced without sexual intercourse, and merely by great nervous excitement; and he is not prepared peremptorily to decide the question even with regard to the human female ; but considers, nevertheless, a " fabi- form corpus luteum, with an . asteriskal cavity," &c. &c., as strong presumptive proof of impregnation. J. Miiller§ regards the discharge of ova as a consequence of sex- ual intercourse, and must therefore hold the same opinion with re- gard to corpora lutea. " In mammalia," he says, "the separation of the ovum from the ovary seems to be dependent on the act of im- pregnation. It has, it is true, been stated that cicatrices of the ova- ries, resulting from the escape of ova, have been seen in the bodies of virgins ; but this is certainly no ordinary occurrence." Dr. Carpenterjl adopts principally Montgomery's description of the corpus luteum, and his opinion that it is a good sign of impreg- nation. He has, however, no original observations on the subject. He also regards as " not improbable," the theory that ova are ma- tured and discharged, at each menstrual period, independently of fecundation ; though he thinks, with Dr. Barry, that it is more likely * S. D. Gross, Elements of Pathological Anatomy, Philad. 1845. ■j" Illustrations of some of the Diseases of the Ovaria, London 1830. J On Diseases of Woman, Philad. ed. 1840. § Miillers Physiology, Philad. ed. 1843. II Principles of Human Physiology, Philad. ed. 1843. INTRODUCTION". 9 that the matured ova retrograde and become absorbed, without hav- ing been discharged. Dr. Robert Lee* admits a distinction between true and false cor- pora lutea, or those connected with impregnation and those arising from other causes. His ideas, liowever, regarding the precise pro- cess which takes place in menstruation do not seem to be very clear- ly announced; for, although he considers it probable that about the menstrual period there is a rupture of the Graafian vesicle, he nevertheless denies that an ovum is discharged at this time. "That an ovum," he says, " does not pass from the ovarium during men- struation is evident from the fact that an ovum is never found but as a consequence of impregnation, and that conception does not take place during the menstrual period. "f He describes the yellow mat- ter of the corpus luteum as situated externally to both layers of the Graafian vesicle, without anything interposed between it and the ovarian tissue. Dr. Robert Paterson has two papers on this subject in the Edin- hurgh Medical and Surgical Journal, in the first of which (January, 1840) he gives a somewhat extended notice of the distinguishing marks of "true corpora lutea," i.