P. Eckstein

A Study of Uterine Embryos Recovered from Rhesus Monkeys Fitted with Intrauterine Devices

Fifteen mature female rhesus monkeys were mated and operated upon to recover preimplantation uterine embryos. This resulted in the recovery of 25 embryos or unfertilized ava in 43 attempts. The same animals were fitted with plastic intrauterine devices (IUDs) and the recovery procedure was repeated. In this series 61 recovery attempts yielded only 10 embryos, 7 of which were sectioned and analyzed by transmission electron microscopy. This approach revealed the ultrastructural details of embryo degeneration and leukocyte association seen in embryos recovered from IUD-bearing animals. Samples of peripheral venous blood were analyzed for levels of ovarian steroids at the time of embryo recovery. The results are discussed in relation to the mechanism of action of IUDs.

Studies on uterine flushings in the baboon

Abstract A method is outlined for obtaining uterine flushings per vaginam from adult baboons without the need for laparotomy. Evidence for the validity of the flushing technique is given. The effects of intrauterine contraceptive devices (IUDs) on the cellular and protein composition (determined by disc electrophoresis in polyacrylamide) of the flushings obtained by this method are described. Polymorphonuclear leukocytes and, to a lesser extent, mononuclear cells were present more frequently and in increased numbers in animals with IUDs. The disc electrophoretograms of the flushings did not differ markedly either between individual baboons or after insertion of an IUD. A system for coding the protein band patterns found in flushings is described; a maximum of 18 bands was observed. Most, but not all, bands were present in blood plasma. One of the uterine-specific proteins may be identical with the glycoprotein previously demonstrated in tubal fluid of women and monkeys. An extra protein band tended to appear in baboon uterine flushings collected after ovulation. Blastokinin does not seem to occur in the uterine fluid of baboons.

Studies on uterine flushings in the baboon: II. The effect of an intrauterine contraceptive device on certain biochemical parameters

This paper reports on the concentration of total protein, reducing sugar, and various enzymes in uterine flushings obtained from 17 mature, regularly cyclic baboons and stored at -10 degrees C until required. It was found that the levels of total protein and reducing sugar was high at both the early proliferative and late secretory stages of the menstru al cycle and fell to their lowest levels in the early secretory phase. When an IUD was in situ, higher levels of these 2 constituents occurred. Of the enzymes measured in the early secretory phase, only hemoglobinase was significantly elevated in the presence of an IUD. Trypsin, chymotrypsin, lysozyme, amylase, and phosphatase were usually detectable in the flushes, but none was significantly altered by the device. The possible biologic implications of these findings are discussed.

Transcervical uterine catheterization in rhesus monkeys

Abstract A technique for inserting catheters and other materials into the uterine cavity of rhesus monkeys, per vaginam, with minimal trauma, has been described. Some applications of the technique are given.

Immunochemical composition and gel filtration profiles of uterine flushings from rats with and without IUDs

Abstract The composition of uterine fluids collected from pro-oestrous rats with unilateral intrauterine sutures was determined by immunoelectrophoresis and gel filtration. Immunochemical analysis with an anti- (blood plasma) serum showed a markedly altered uterine environment on the IUD side; 7–9 and 16–22 components, respectively, were found in control — and IUD-horn flushings. The gel filtration profile of the uterine flushings revealed three components; one of the low molecular weight components was significantly raised in the IUD horn (p The possible relation of these findings to the mechanism involved in the action of an IUD in the rat is discussed.

Studies on uterine flushings in the baboon: III. Immunochemical composition in animals with and without intrauterine contraceptive devices

Abstract The immunochemical composition of uterine flushings and blood plasma taken from baboons, either with or without intrauterine contraceptive devices (IUDs), in the early secretory phase of the cycle was determined by quantitative electrophoresis. Characteristic, but dissimilar, patterns were obtained from the flushings and plasma; they were unaffected by the presence of an IUD. Nine components were demonstrable in the uterine flushings, and at least as many were found in the plasma. In the IUD-fitted animals, the level of one uterine component, considered to be transferrin (electrophoretic mobility [Mr] = 0.50), was significantly raised, while that of a blood plasma constituent (Mr = 0.17) was significantly lowered. The relation of these findings to comparable studies in women and lower mammals and their possible implications on the mode of action of IUDs are discussed.

Effect of uterine fluid from mice with IUDs and various chemical compounds on mouse eggs in culture.

Abstract Neat uterine fluid from the IUD horn of pro-oestrous mice is slightly more toxic than control horn fluid to mouse morulae and 2-cell eggs in culture. The toxic action is completely eliminated when IUD-horn fluid is diluted with culture medium. The effects of various chemical compounds that may be elevated in the IUD horn were also tested in the egg culture system. Only a few of the compounds were found to be toxic. The significance of these results in relation to the contraceptive effect of the device is discussed.

Peripheral plasma progesterone and oestradiol concentrations associated with successful and unsuccessful recovery of uterine embryos in rhesus monkeys with and without intra-uterine devices

Concentrations of progesterone and oestradiol were measured in peripheral plasma samples collected at the time when the uteri of rhesus monkeys with an intra-uterine device (IUD) and those without an IUD were flushed in attempts to recover uterine embryos. The proportion of successful attempts in IUD-bearing monkeys was much lower than in the non-IUD-bearing animals. Steroid measurements indicated that this reduced success rate was not due to an effect of the IUD on the timing of ovulation within the menstrual cycle or to a steroid-mediated disturbance in the rate of embryo transport to the uterine lumen. Successful embryo recoveries were associated with a higher progesterone concentration, suggesting that one reason for failure was that the attempt had been made too close to ovulation. There was no evidence of any asymmetry between the left or right ovaries in their ovulatory or steroidogenic activity.