Search PubMed⌕ Search

Biomedical subjects

D R Mishell

Publications and source records attributed to D R Mishell.

At least 19 recordsLinked to original sources
PubMed2001

Early pregnancy termination with vaginal misoprostol combined with loperamide and acetaminophen prophylaxis.

The objectives of this prospective non-concurrent cohort study were to confirm the efficacy of vaginal misoprostol for early pregnancy termination and to determine whether the incidence of side effects is lower with prophylactic loperamide and acetaminophen. Two-hundred women with an intrauterine pregnancy < or =56 days gestational age seeking medical pregnancy termination in an ambulatory research clinic were enrolled in the study. One-hundred participants (group 1) ingested 4 mg of loperamide and 500 mg of acetaminophen before the vaginal placement of 800 mirog of misoprostol moistened with 2 mL of saline. If abortion had not occurred, the same regimen was repeated every 24 h (maximum three doses). One-hundred participants (group 2) from the same clinic who previously underwent the same misoprostol regimen without prophylactic medication served as a control group for comparison with respect to abortion success and the incidence of side effects. The rate of successful abortion was not statistically significantly different between the two groups (group 1 93%, group 2 89%). The incidence of opiate analgesic use was significantly less in group 1 (4%) compared with group 2 (16%) (OR 0.22, 95% CI 0.06-0.73, p = 0.01). There was a significantly lower incidence of diarrhea in group 1 (23%) compared with group 2 (44%) (OR 0.38, 95% CI 0.20-0.73, p = 0.003). There was no difference in the incidence of fever/chills or the incidence of emesis between the two groups. Vaginal misoprostol is effective for termination of pregnancy < or = 56 days and the incidence of diarrhea and the use of opiate analgesia is significantly reduced with prophylactic loperamide and acetaminophen.

Abortifacient Agents, Nonsteroidal↗
PubMed2001

Ovarian function during use of vaginal rings delivering three different doses of Nestorone.

Contraceptive vaginal rings delivering various progestins alone or in combination with estrogen have been previously studied, showing adequate steroid vaginal absorption and acceptability by the users. Nestorone progestin (NES) is a potent 19-nor-progesterone derivative, inactive by the oral route, but an excellent option for vaginal delivery. The purpose of this study was to evaluate ovarian function during 6 months of continuous use of progestin-only vaginal rings delivering 3 different doses of NES: 50, 75, and 100 microg per day. Blood samples were taken twice a week for 5 consecutive weeks during a control cycle and on months 1, 3 and 6 of use, for the measurement of estradiol (E2), progesterone (P), and NES. A total of 87 volunteers randomly received each of the 3 doses. After an initial peak, NES serum levels remained fairly constant throughout the duration of the study at about 125, 200 and 250 pmol/L, respectively, decreasing slightly with time. Luteal activity occurred very rarely (1.2-2.6% of sampling periods) with no apparent difference between doses. Low E2 levels (< or =100 pmol/L) in all samples of a run were rare (5%) and only with the high dose ring (100 microg/day). E2 remained within normal levels (101-1500 pmol/L) in most of the segments studied. We conclude that the 50 and 75 microg/day NES rings provide adequate ovulation inhibition without hypoestrogenism, while the 100 microg/day ring may deliver an unnecessarily high dose.

Administration, Intravaginal↗
PubMed2001

Levonorgestrel concentrations during 7 years of continuous use of Jadelle contraceptive implants.

Serum levonorgestrel concentrations were assayed in a multicenter, 7-year study of 199 users of Jadelle rod implants. We examined drug levels, patterns of changes, factors affecting drug levels, and concentrations at which pregnancies occurred. Mean levonorgestrel concentrations declined from 435 pg/mL at 1 month of use to 64% of that value (280 pg/mL) at the end of 3 years. Between the end of the third and fifth years neither mean nor median serum levels varied markedly. At 5 years the mean concentration was again 64% of the first month's mean. Declining levels were observed thereafter through the end of 7 years when the mean, 224 pg/mL, was 52% of the 1-month value. Last measured drug concentrations of women who became pregnant during Jadelle use had mean and median values of 152 and 144 pg/mL, respectively, and a maximum value of 180 pg/mL. Analyses indicated ponderal index, body weight, duration of use, and a single clinical center were the most important variables affecting measured levonorgestrel levels. Approximately one-third of assays in the sixth and seventh years were found to be below 180 pg/mL, suggesting that Jadelle levonorgestrel implants would not maintain sufficiently high levels of effectiveness against pregnancy after 5 years and that heavier women would then be at greater risk of pregnancy.

Adolescent↗
PubMed2001

A prospective randomized trial comparing clomiphene citrate with tamoxifen citrate for ovulation induction.

OBJECTIVE: To compare the rates of ovulation and pregnancy after tamoxifen citrate (TMX) or clomiphene citrate (CC) among anovulatory women with infertility. DESIGN: Prospective randomized trial. SETTING: Infertility clinic in a university teaching hospital. PATIENT(S): Eighty-six anovulatory women under 40 years of age undergoing ovulation induction. INTERVENTION(S): The women were assigned randomly to receive either TMX or CC on cycle days 5-9. MAIN OUTCOME MEASURE(S): Rates of ovulation and pregnancy for the two treatment modalities. RESULTS(S): The overall rate of ovulation in the TMX group was 50 of 113 (44.2%) and in the CC group, 41 of 91 (45.1%). There were 10 pregnancies in the TMX group and 6 pregnancies in the CC group. The cycle fecundity per ovulatory cycle was 20.0% in the TMX group and 14.6% in the CC group. CONCLUSION(S): The overall rate of ovulation and pregnancy were similar with TMX and CC. TMX is a suitable alternative agent to CC in the management of anovulatory infertility.

Adult↗
PubMed2001

Pharmacokinetics of testosterone after percutaneous gel or buccal administration.

OBJECTIVE: To determine the pharmacokinetics of testosterone following its administration using transdermal gel or buccal lozenges. DESIGN: Pilot study. SETTING: University-based hospital. PATIENT(S): Ten bilaterally oophorectomized women. INTERVENTION(S): Daily micronized testosterone gel (1 mg) and testosterone propionate lozenge (1 mg). MAIN OUTCOME MEASURE(S): Total testosterone, androstenedione, dihydrotestosterone, 3alpha-androstanediol glucuronide, and sex hormone-binding globulin were measured in serum by specific radioimmunoassays; free testosterone levels were also calculated. RESULT(S): Before treatment, serum testosterone levels in the groups using the lozenge and gel were 16 +/- 4.0 and 20 +/- 6.0 ng/dL, respectively. Mean maximum testosterone levels obtained with the lozenge occurred 1 hour after administration on days 1 (692 +/- 236 ng/dL) and 14 (836 +/- 309 ng/dL) of treatment and fell precipitously thereafter. In contrast, testosterone levels obtained with the gel showed a prolonged rise reaching maximal levels of 97 +/- 78 and 100 +/- 60 ng/dL after 18 hours. The serum level patterns of free testosterone, dihydrotestosterone, and 3alpha-androstanediol glucuronide were similar to the corresponding total testosterone levels. CONCLUSION(S): Administration of testosterone lozenge by buccal absorption produced a rapid and brief elevation of testosterone levels, with levels reaching upper limits of the male range. In contrast, transdermal testosterone gel absorption resulted in a prolonged elevation of testosterone levels, which were in the hyperandrogenic female range but resembled steady state pharmacokinetics.

Absorption↗
PubMed2001

Contraceptive vaginal rings.

Contraceptive vaginal rings (CVRs) contain sex steroids that diffuse through a plastic polymer ring at a constant rate and are absorbed directly through the vaginal epithelium into the systemic circulation. This delivery system provides many advantages over oral contraceptives (OCs), including avoidance of the first-pass effect through the liver, constant serum steroid levels, longer duration of use, and greater bioavailability of the hormones. CVRs containing progestin only are designed for continuous use for 3 to 6 months. Those containing progesterone alone are indicated for use in women who are breastfeeding. Large clinical trials of progestin-containing CVRs demonstrated good efficacy and safety of the CVR, with continuation rates similar to that of OCs. CVRs containing a combination of estrogen and progestin are designed to be used for 1 to 12 months in a cyclic manner similar to OCs, with withdrawal bleeding in the fourth week of each cycle. In clinical trials these CVRs have typical use efficacies similar to OCs, with an acceptable pattern of bleeding.

Administration, Intravaginal↗
PubMed2000

Vaginal epithelial surface appearances in women using vaginal rings for contraception.

Vaginal inspections using colposcopy before insertion of contraceptive vaginal rings and at 2-month intervals during ring use were conducted on 169 users of four different formulations. The rings studied released Nestorone alone (50, 75, 100 g daily over 6 months); ethinyl estradiol: Nestorone (30:100 and 15:150 g daily over 6 months); ethinylestradiol:norethindrone acetate (20:1000 and 15:1000 g daily over 4 months); and ethinyl estradiol:norethindrone acetate (20:1000 g daily over 12 months). A total of 88 altered or atypical conditions of the vaginal surface appearance were recorded in 507 inspections (17.4% of inspections). Many of these atypical appearances were quite subtle. The incidence was significantly higher (p <0.01) than in the single pretreatment examinations (11 in 158 inspections; 7.0%), but closely matched that of a "control group" of sexually active women who were the subject of an earlier study by the same investigators. In that study, the incidence was 18% (57 atypical conditions in 317 inspections). In all, 83% of atypical conditions identified in the vagina during ring use had disappeared by the next scheduled colposcopy despite continued ring use. Findings of potential significance were conservatively defined as all ulcerations, those abrasions and ecchymoses that were >0.5 cm in any direction, and fields of five or more petechiae. Findings fitting those criteria comprised 30% of atypical conditions in ring users, 33% in the control group, and 27% pretreatment. The corresponding incidence as a percentage of inspections were 5.3%, 6. 0%, and 2.5% in the ring users, control groups, and pretreatment groups, respectively. These differences were not statistically significant. The findings suggest that the vaginal rings included in the studies contributed little, if at all, to clinically significant lesions or to total lesion incidence. Further definition would require a larger and longer-term study with matched controls.

Adolescent↗
PubMed2000

Ovarian function during use of Nestorone(R) subdermal implants.

Nestorone(R) progestin (NES) is a potent 19-nor-progesterone derivative which is biologically inactive when administered orally; however, it is an excellent option for implant contraception. The objective of this study was to evaluate ovarian function during use of either one 4-cm or two 3-cm NES implants for 24 months. A total of 60 volunteers were enrolled in each dose group. Vaginal ultrasound (VUS) and blood sampling for determinations of estradiol (E(2)), progesterone (P) and NES serum levels were carried out twice a week for 6 consecutive weeks, beginning in months 1, 6, 12, 18, and 24 of implant use. Serum levels of NES declined with time, with a more pronounced decrease during the first 18 months of implant use; thereafter, NES levels remained stable until the end of the study at 24 months. Luteal activity was very infrequent during the first year of use (<3%) but increased during the second year, occurring in 27% and 35% of the sampling periods in the 1-implant group, and 2% and 16% of the sampling periods in the 2-implant group, at months 18 and 24 of use, respectively. No luteal activity was observed with NES levels above 80 pmol/L. Serum P levels in periods of luteal activity were significantly lower than those of controls. Persistent anovulatory follicles were the most common VUS finding and this was associated with E(2) levels that remained within the normal range (101-1500 pmol/L) in the majority of the sampling periods studied. Considering that a single implant offers advantage for insertion and removal, a new single NES implant is being developed with a slightly higher release rate, to reduce effectively the incidence of ovulation and provide a greater margin of safety beyond 2 years.

Adolescent↗
PubMed2000

Prolonged effectiveness of Norplant(R) capsule implants: a 7-year study.

Soft tubing Norplant(R) contraceptive implants were studied in 1210 women for 7 years to measure the duration of effectiveness and the magnitude of the pregnancy rates over that time. Mean age at enrollment was 27.4 years. Of the enrollees, 42% were US residents. One-sixth (16.1%) weighed >/=70 kg at the time of implant placement. At the end of 5 years, the cumulative pregnancy rate was 1.1/100; at the end of 7 years, it was 1.9/100. No pregnancies occurred to any of the 400 women who enrolled in the study at age >/=30 years and who weighed <100 kg. Among women aged 18-33 years, the 7-year Norplant pregnancy rates are comparable to the median pregnancy rates of tubal sterilization methods for women of the same age and duration of use. For women aged >/=34 years, without regard to weight at admission, the 7-year effectiveness of soft tubing Norplant equals or surpasses that of tubal sterilization. For continuing implant users, annual pregnancy rates <1.0/100 in years 6 and 7, together with low cumulative pregnancy rates, testify that Norplant capsule implants remain highly effective for 7 years.

Adolescent↗
PubMed2000

Comparison of ovarian follicular activity during treatment with a monthly injectable contraceptive and a low-dose oral contraceptive.

Ovarian follicular development occurs during treatment with combined and progestin-only oral contraceptive (OC) pills and progestin-containing subdermal implants, and can be associated with the development of persistent functional cysts that may require surgical removal. Lunelle is a once-a-month injectable contraceptive containing estradiol cypionate 5 mg and medroxyprogesterone acetate 25 mg. A randomized, comparative study was undertaken to compare the effect on ovarian follicular activity associated with use of Lunelle and a low-dose OC. A total of 30 ovulatory subjects were randomly assigned to receive two cycles of treatment with either an OC containing ethinyl estradiol 20 microg and 0.1 mg levonorgestrel or Lunelle. During the second cycle of treatment, pelvic sonography was performed every 4 days, at which time the maximum follicle diameter was measured. Study end points were the presence of follicles >/=10, 20, and 30 mm. In all, 13 of 15 subjects in the OC group and 14 of 15 in the Lunelle group completed the study. Follicles measuring >/=10 mm were present in 11 of 13 (84.6%) in the OC users and in four of 14 (28.6%) in the Lunelle users (p <0.05). In the OC group, six of 13 subjects (46.1%) developed follicles >/=20 mm, and one of 13 (7.7%) developed follicles >/=30 mm. No subjects in the Lunelle group developed a follicle >/=20 mm in diameter. This study indicates that Lunelle is associated with a significantly lower incidence of ovarian follicular development compared to that of an OC containing 20 microg ethinyl estradiol and 0.1 mg levonorgestrel.

Adult↗
PubMed2000

Mifepristone for preinduction cervical ripening beyond 41 weeks' gestation: a randomized controlled trial.

OBJECTIVE: To compare the effect of mifepristone with placebo on cervical ripening before labor induction in prolonged pregnancies. METHODS: One hundred eighty women with pregnancies beyond 41 weeks and undilated, uneffaced cervices were assigned randomly to receive mifepristone 200 mg or placebo and observed for 24 hours. We then gave intravaginal misoprostol 25 microg every 4 hours or intravenous oxytocin. We expected 60% of placebo-treated and 80% of mifepristone-treated women to deliver vaginally within 48 hours. RESULTS: Among 180 subjects, 97 received mifepristone and 83 received placebo. The mean interval (+/- standard deviation [SD]) from start of induction to delivery was 2209 +/- 698 minutes for mifepristone-treated subjects and 2671 +/- 884 minutes for placebo-treated subjects (P <.001, log-transformed data). Twelve (13. 6%) mifepristone-treated women and seven (10.8%) placebo-treated women delivered vaginally on day 1 (P =.60). After 24 hours, the median Bishop score for both groups was 3 (0-11) (P =.51). One hundred thirty-one subjects required misoprostol, 65 (67.0%) were mifepristone-treated women, and 66 (79.5%) placebo-treated women (P =.06). The median (range) oxytocin dose was 871.5 (0-22,174) mU for mifepristone-treated women and 2021.0 (0-24,750) mU for placebo-treated women (P =.02). Seventy-seven (87.5%) mifepristone-treated women and 46 (70.8%) placebo-treated women delivered vaginally 48 hours after the start of treatment (P =.01). There were nine cesareans in the mifepristone group and 18 in the placebo group (P =.02). More nonreassuring fetal heart rate patterns and uterine contractile abnormalities occurred in mifepristone-treated subjects. There were no statistically significant differences in neonatal outcomes between groups. CONCLUSION: Mifepristone had a modest effect on cervical ripening when given 24 hours before labor induction, appearing to reduce the need for misoprostol and oxytocin compared with placebo.

Adult↗
PubMed1999

Early pregnancy termination with intravaginally administered sodium chloride solution-moistened misoprostol tablets: historical comparison with mifepristone and oral misoprostol.

OBJECTIVE: The purpose of this study was to compare the abortifacient effect of intravaginally administered moistened misoprostol tablets with that of the combination regimen of mifepristone and oral misoprostol. STUDY DESIGN: One hundred women at </=56 days' gestation received 800 microg misoprostol intravaginally in the form of sodium chloride solution-moistened tablets. The dose was repeated 24 hours later if a gestational sac persisted on ultrasonographic examination. These 100 subjects (group 1) were then matched with 100 subjects who had received 600 mg mifepristone followed by 400 microg misoprostol orally as part of a large multicenter American trial (group 2). Subjects were monitored for abortion success, adverse side effects, and bleeding characteristics. Abortion failure was defined as persistence of an intrauterine sac or the need to perform a surgical evacuation of the uterus for hemorrhage, for incomplete abortion, or at the subject's request. RESULTS: In 88 of the 100 women in group 1 and 94 of the 100 women in group 2, abortion occurred and a surgical procedure was not required. Abortion rates were not influenced by gestational age in either group. Prostaglandin-related side effects of fever and chills, vomiting, diarrhea, and uterine pain were all significantly higher in group 1. Excessive uterine bleeding was uncommon in both groups, and no subjects received blood transfusions. CONCLUSION: The abortion rate with intravaginally administered moistened misoprostol tablets is similar to that with the combination of mifepristone and oral misoprostol. However, intravaginal administration of misoprostol is associated with significantly more prostaglandin-related side effects.

Abortifacient Agents, Nonsteroidal↗
PubMed1999

Estradiol-delivering vaginal rings for hormone replacement therapy.

OBJECTIVES: This study was undertaken to determine the relief of climacteric symptoms by vaginal rings delivering estradiol and to monitor estrogen levels. STUDY DESIGN: Rings releasing in vitro either 60 or 140 microg/d estradiol were used by 35 women who had undergone hysterectomy for each dose level. Hot flash and night sweat incidences, vaginal conditions, and complaints were recorded at clinic visits pretreatment and at 1 week, 2 weeks, 1 month, and monthly thereafter through 6 months. Serum samples were assayed for estradiol, estrone, and estrone sulfate. RESULTS: Hot flash incidence was reduced by about 80% with either ring. Vaginal conditions and mood were improved. Fourteen of 70 women discontinued ring use during the trial, 5 because of ring expulsions. Mean (+/-SD) estradiol levels were 123 +/- 48 and 307 +/- 93 pmol/L for the low and high dosage levels, respectively. Mean estrone levels exceeded estradiol levels by 1.7-fold for the higher dosage ring and 2.6-fold for the lower dosage ring. Increases in estrone sulfate concentrations were many times greater than those of estradiol or estrone. CONCLUSIONS: Vaginal rings are an acceptable method of delivery for periods of >/=6 months of doses of estradiol that reduce vasomotor symptoms and improve vaginal conditions. There was little difference in these responses between the 2 dosage levels.

Administration, Intravaginal↗