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Although no ionizing radiation is involved, patients undergoing magnetic resonance imaging (MRI) are exposed to powerful static magnetic fields, magnetic field gradients, and radio-frequency fields that may be potentially damaging. Our study aims to document the effect of MRI imaging sequences on early murine embryo development (two-cell to blastocyst stage) in vitro. Two-cell murine embryos were exposed to various lengths of MRI using pulse sequences employed in present day clinical imaging. Early murine embryo development was documented in vitro, and blastocyst development rates were computed for both the control and exposed groups. There were no significant differences detected in the rate of blastocyst formation between the control groups and the embryos exposed to MRI. J. Magn. Index terms: MRI; murine blastocyst; in-vitro development; safety; embryogenesis ALTHOUGH NO IONIZING RADIATION is involved, patients undergoing MRI are still exposed to powerful static magnetic fields, magnetic field gradients, and radio frequency (RF) fields that may potentially be damaging. While a few authors (1-3) have studied the effects of MRI on pregnant mice in mid-gestation, no work has been done to study the effect of pulse sequences utilized for present-day routine NMR scanning on early embryo development. Our study aims to document the effect of modern MR Imaging sequences on early murine embryo development (two-cell to blastocyst stage) in vitro. MATERIALS AND METHODSNewly arrived three-to four-week-old female CBA/C57 Fl mice were allowed to acclimatize for one week in a windowless room at the University's Animal Holding Unit. The males were kept individually in separate cages. Lighting was controlled by an automated timer that provided 12 hours of light and 12 hours of darkness. The temperature and relative humidity were maintained at 22°C and 70%. Water and food pellets were provided ad libidum.The female mice were superovulated with intraperitoneal injections of 10 IU PMSG (Folligon; Intervet, Boxmeer, Holland), and 48 hours later 10 IU of hCG (Chorulon; Intervet, Boxmeer, Holland). The females were then mated with proven-fertile Swiss Albino. Mating would usually occur around midnight, and the females would be checked the following morning for the presence of vaginal plugs, which indicated successful mating.The successfully mated females were then killed by cervical dislocation 36 -40 hours post hCG injection. The mice were dissected and both the oviducts were recovered and washed in T6 ϩ 4BSA. Under a stereo dissecting microscope, clusters of two-cell embryos were seen in the ampullary region of the oviduct. The oviduct was then teased with a pair of 21G, 1 1 2 -inch hypodermic needles in fresh medium. The embryos obtained were then washed 4 times in 40 -60 L of T6 ϩ 4BSA under paraffin oil. These two-cell embryos were transferred to a fresh dish containing about 100 L of T6 ϩ 4BSA under paraffin oil for culture and incubated at 37°C in a humidified atmosphere of 5% CO 2 in air.Embryos were then transported from th...

Objective To test the hypothesis that women with pelvic venous congestion have a reduction of reactivity of their peripheral circulation. DesignComparison was made between 20 women with chronic pelvic pain due to congestion and a control group of 15 pain-free women matched for age, parity and body weight. A comparison of these results was made with those from six postmenopausal women taking hormone replacement therapy.Methods Study and control groups were investigated during the mid-follicular phase of the menstrual cycle (days 5-9) and the mid-luteal phase (days 19-23). The study group was also investigated during the fifth month of treatment with suppression of ovarian activity with leuprorelin or medroxyprogesterone acetate or six months after hysterectomy and bilateral salpingo-oophorectomy. Head-up tilt sufficient to increase intra-vascular pressure in the toe by a standard 40 mmHg was used as a means of raising venous pressure in the lower limb. Skin capillary red blood cell velocity (flux) was measured using a laser Doppler flow probe placed over the pulp of the big toe. Heart rate and blood pressure were also recorded. The change in skin blood flow following head-up tilt was expressed as a percentage of baseline flow in the supine position.Main outcome measures Percentage change in skin red blood cell flux, heart rate and blood pressure in response to 40" head-up tilt. ResultsIn the control group the median response to head-up tilt in the follicular phase was one of a reduction in flux, whereas in the luteal phase it was more variable ranging from an increase to a decrease in flux. The responses in the pelvic congestion group in both the follicular and luteal phases were similar to those of the control group in the luteal phase. A small but significant increase in heart rate in response to tilt in the pelvic pain group, compared with the control group, was interpreted as being due to a fall in venous return. Treatment of the pelvic congestion group by medical suppression of ovarian activity or total hysterectomy with bilateral salpingo-oophorectomy resulted in a significant change in response to head-up tilt from the variable type of luteal response to one of a more constant reduction in flux, similar to that of the control group in the follicular phase. A reduction in flux was also found consistently in postmenopausal women. ConclusionThe study confirms the hypothesis that women with pelvic pain due to congestion show a change in peripheral vascular reactivity which returns to normal after suppression of ovarian activity. It seems likely that some alteration of normal ovarian function is responsible for the observed changes in peripheral blood flow in response to a rise in venous pressure in women with pelvic congestion.

Sweeping of the membranes during induction of labor had a beneficial effect on labor and delivery, which appeared to be limited to nulliparas with unfavorable cervices who needed cervical priming with PGE(2).

Women with pregnancy-induced hypertension have abnormal cutaneous vascular reactivity that returns to normal after delivery.