[Histological reaction of the endometrium to irritation by a probe in relation to the problem of embryo transfer during in-vitro fertilization].

The purpose of this study was to try to explain morphologically why a high percentage of artificially inseminated embryos fail to implant after intrauterine transfer. To investigate the problem we irritated with a probe the endometria of 31 women of child-bearing age a few days before their scheduled hysterectomies. Our histological studies of the uteri were directed towards learning whether a localised decidual change had developed at the site of mechanical irritation. In addition, we measured the serum values of FSH, LH, prolactin, progesterone, beta-estradiol, and cortisol of 22 of the patients on the day of mechanical irritation of the endometrium and on the day of hysterectomy. At the time of probe insertion six patients were in the proliferative phase. In three the endometrium responded with a slight crowding of enlarged stromal cells in the region of mechanical irritation. In three it failed to respond. In five patients who had continued to take oral contraceptives until their hysterectomy the endometrium also showed no response. In twelve patients of 17 in the secretory phase we found a focal predecidual to decidual change of the stroma. The hormonal values of these women were within normal limits. In the remaining five patients we found a deficient secretory phase without any evidence of decidual change. The serum values of progesterone for these patients were low. The results allow us to suggest that the mechanical irritation from transfer of an in vitro fertilised embryo in the early secretory phase might induce a premature decidual change, which could inhibit implantation of the embryo.