Ectopic gestation: a consideration of new and controversial issues relating to pathogenesis and management.

In this chapter on ectopic gestation are have attempted to elucidate new and controversial issues in this area. In summary, we identify the following items as "nominative imperatives": I. Meticulous review of the classic etiologic concepts of ectopic gestation indicates that these concepts are no longer tenable although certain of them may be operative in specific instances. Review of certain veterinary work, animal experimentation, and pathologic and clinical observations in primates lends support to the hypothesis that failure of the ovum to implant may be related to delayed (post-midcycle) ovulation followed by shortening of the luteal phase with defective endometrial development and by a bleeding episode that simulates menstruation. II. Review of the literature indicates that the woman who has a tubal pregnancy has about a 50 to 60 percent chance of never becoming pregnant again. Among those who do conceive, at least 10 percent, and possibly more, develop another ectopic gestation. Only one-third of the women who have a tubal pregnancy will ever succeed in delivering a healthy child. Obviously this unhappy prognosis is the basis for many of our recommendations for management. The woman who had had a tubal pregnancy should consider the use of mechanical contraception after the midcycle to prevent recurrent ectopic pregnancy. This is obviously a suggestion based on the etiologic theory that we espouse. The prophylactic use of anti-Rh immunoglobulin is necessary in ectopic gestation in Rh-negative gravidas. III. In terms of the relation of ectopic pregnancy to intrauterine devices, the most authoritative statement than can be found is that of Lehfeldt, who states that the IUD is 99.5 percent effective in preventing intrauterine pregnancy, 95 percent effective in preventing tubal ectopic gestation, and is ineffective against ovarian implantation. Nonetheless, the fact that one in 23 IUD pregnancies is ectopic makes consideration of this diagnosis mandatory. IV. In terms of diagnostic assistance that can be provided by the radiologist, a comprehensive summary of their capabilities is presented. Laparoscopy is considered a valuable aid in establishing the diagnosis of unruptured ectopic pregnancy. A new, highly sensitive radioimmunoassay with specific affinity for the beta subunit of HCG is described that can detect very low levels of HCG when routine pregnancy tests are negative. It appears that this test can be of enormous help in diagnosing the early, unruptured tubal pregnancy. V. In a consideration of the role of conservative operations in the management of tubal pregnancy, we take the position that the modern gynecologist must acknowledge the possibility of conservative operations. It is obvious that success is most likely, when the surgeon is confronted with an early, unruptured ectopic gestation and that the feasibility of a linear salpingostomy must be acknowledged. VI...