Effect of an Intrauterine Device on Menstrual Cyclicity and Luteal Function in the Baboon

Abstract

In the baboon, the presence of an IUD slightly shortens the length of the menstrual cycle and prolongs that of menstruation. Sexual skin changes showed that the part of the cycle shortened was the detumescent (= secretory) phase, the tumescent (= proliferative) phase remaining unaffected. Plasma progesterone levels during the latter half of the cycle were not affected by the IUD, but the onset of menstruation in experimental animals was associated with a higher blood concentration of progesterone than that present in controls. It is concluded that an IUD does not interfere with luteal function in the baboon.

The Effect of Intrauterine Contraceptive Devices on Ovarian and Menstrual Function in the Human

“…It was concluded that the shortened luteal phases of the IUCD cycles were not due to earlier regression or deficiency of the corpus luteum but to a local effect which caused the endometrium to be shed earlier in the ovarian cycle. Almost identical findings have been reported for the baboon (31). The earlier onset of bleeding would advance the timing of the next IUCD cycle calculated from menstrual data relative to that calculated from ovarian data.…”

Uterine histology and prostaglandin concentrations and utero-ovarian venous steroid and prostaglandin concentrations during the luteal phase of the menstrual cycle in baboons (Papio spp.) with or without an IUD

“…The typical variation in the peripheral plasma progesterone concentration measured during the menstrual cycle, shown in Text- fig. 1, is similar to that described by Stevens, Sparks & Powell (1970) and Breed et al (1972).…”

“…The animals used were taken from a group of about 40 adult, mature baboons (Papio anubis, P. cynocephalus, P. papio and P. ursinus) maintained within the department, the management being similar to that described for rhesus monkeys by Eckstein, Kelly . They were observed daily for the appearance of menstrual blood on the perineum, and the size and colour of the sex skin was assessed subjectively (Breed et al, 1972). The typical variation in the 'sex skin score' during a menstrual cycle, shown in Text- fig.…”

“…The typical variation in the 'sex skin score' during a menstrual cycle, shown in Text- fig. 1, is similar to that described by Breed et al (1972). The IUDs, shortened Margulies Spirals (polyethylene about 0-1 cm thick and 2 cm diam¬ eter), were inserted via a puncture wound through the uterine wall during laparotomy under halothane-02 anaesthesia at least 5 weeks before the onset of the menstrual cycle in which the experiment was performed; the presence of the IUD was subsequently checked by radiography.…”

“…Baboons fitted with an intrauterine device (IUD) menstruate when there is a higher (1-51 ng/ml) peripheral plasma progesterone concentration than do baboons without such a device (0-60 ng/ml; Breed, Stephenson, Eckstein, Peplow & Butt, 1972), indicating that the IUD may alter the sensi¬ tivity of the uterine endometrium to circulating progesterone, as it does in rats (Psychoyos, 1966; Chaudhury & Sethi, 1970) and mice (Martin & Finn, 1970). Marston, Kelly & Eckstein (1971) found that the injection of arachis oil into the oviducts traumatized the uterine endometrium, stimulating a deciduomal reaction similar to the epithelial plaque formed during implantation in non-IUD and IUD-bearing rhesus monkeys with and without exogenous progesterone.…”