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Featured researches published by Livia Wan.


Obstetrics & Gynecology | 2006

Progesterone Receptor Modulator for Emergency Contraception A Randomized Controlled Trial

Mitchell D. Creinin; William Schlaff; David F. Archer; Livia Wan; Ron G. Frezieres; Michael A. Thomas; Michael J. Rosenberg; Jim Higgins

OBJECTIVE: Compare the efficacy and adverse effects of CDB-2914, a new progesterone receptor modulator, to levonorgestrel for emergency contraception. METHODS: We performed a randomized, double-blinded noninferiority trial, enrolling healthy women seeking emergency contraception within 72 hours of unprotected intercourse. Participants were randomly assigned to receive a single dose of 50 mg of CDB-2914, plus a placebo 12 hours later or two doses of 0.75 mg of levonorgestrel taken 12 hours apart. Follow-up was scheduled 5 to 7 days after the expected onset of the next menstrual period. Posttreatment pregnancy was established by a positive urine test at follow-up and confirmed by quantitative serum &bgr;-hCG. Daily diaries were used from the time of emergency contraception use until next menses to record adverse effects and sexual activity. RESULTS: Product efficacy was evaluable in 775 of CDB-2914 users and 774 of levonorgestrel users. Pregnancies occurred in 7 (0.9%, 95% confidence interval 0.2–1.6%) and 13 (1.7%, 95% confidence interval 0.8–2.6%) women, respectively. Based on the estimated cycle day of unprotected intercourse, 85% and 69% of anticipated pregnancies, respectively, were averted. Nausea was reported by a somewhat greater percentage of CDB-2914 than levonorgestrel users (29% compared with 24%, P=.03), but the distribution of other adverse effects was similar in both groups. Women in both groups experienced considerable variation in menstrual cycle length as compared with their reported individual normal cycle lengths. CONCLUSION: CDB-2914 is at least as effective as levonorgestrel in preventing pregnancies after unprotected intercourse and has a similar side effect profile. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, www.clinicaltrials.gov, NCT00271583 LEVEL OF EVIDENCE: I


Contraception | 1997

Clinical performance of a new two-rod levonorgestrel contraceptive implant : A three-year randomized study with Norplant® implants as controls

Irving Sivin; Osborn Viegas; Italo Campodonico; Soledad Diaz; Margarita Pavez; Livia Wan; Suporn Koetsawang; Orawan Kiriwat; Manee Piya Anant; Pentti Holma; Kamal el din Abdalla; Janet Stern

In a randomized three-year clinical trial at seven clinics, the performance of levonorgestrel rod (LNG ROD) implants used by 600 women was compared with that of soft tubing NORPLANT implants used by 598 women. No pregnancies occurred in either group of women and, accordingly, body weight did not affect the efficacy of either type of implant. There were neither statistically significant nor important differences in termination rates for any reason over the three years. Complaint and illness rates during use of either of the two implant types were statistically indistinguishable and were attributable to the same set of conditions. Seventy-one per 100 of the women using each implant regimen continued to the three-year point, for an average annual continuation rate of 89 per 100. Removals of LNG ROD implants were accomplished in about half the time required for removal of Norplant capsule implants (p < 0.001).


Obstetrics & Gynecology | 1998

Levonorgestrel capsule implants in the United States: a 5-year study

Irving Sivin; Daniel R. Mishell; Philip D. Darney; Livia Wan; Mercedes F. Christ

Objective To measure effectiveness, adverse event experience, and acceptability of the Food and Drug Administration-approved variant of levonorgestrel capsule implants in the United States through 5 years and to examine determinants of these outcomes. Methods In a prospective, multicenter study, 511 sexually active women selecting contraceptive implants were monitored four times in the 1st year, then semiannually through 5 years. Adverse events were elicited by query and physical examination, and their incidence was measured. Lifetable analyses computed pregnancy and other discontinuation rates. Cox regression models examined effects of age, parity, and preadmission desire for more children on continuation. Removal times were analyzed by analysis of variance. Results Three pregnancies occurred, yielding a 5-year cumulative rate of 1.3 ± 0.8 per 100 users, an average annual rate of three per 1000 women, and an ectopic pregnancy rate of 0.6 per 1000 woman years. No pregnancies occurred to women weighing less than 79 kg. Prolonged or irregular menstrual bleeding, followed distantly by headache, weight gain, and mood changes, was the most frequent medical conditions leading to removal. Weight gain averaged 1 kg per year. Each annual continuation rate was above 80 per 100, for a cumulative 5-year rate of 39 per 100. Continuation was age-dependent, with younger women (younger than 25 years at entry) having lower 5-year continuation rates than older subjects (P < .01). Tissue trauma from deeply placed or poorly aligned implants or severe reactions to local anesthetic affected subjects in 3.1% of removals (nine cases). Conclusion As measured by annual continuation rates of 80 per 100 or higher and annual pregnancy rates below one per 100, implant contraception in the United States was found to be highly acceptable and effective, year after year, regardless of the womans age or family formation status. The cumulative 5-year pregnancy rate, 1.3 per 100, is comparable to that of tubal ligation.


Contraception | 2001

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

Irving Sivin; Livia Wan; Sirpa Ranta; Francisco Alvarez; Vivian Brache; Daniel R. Mishell; Philip D. Darney; Arijit Biswas; Soledad Diaz; Orawan Kiriwat; Manee Piya Anant; Cynthia Klaisle; Margarita Pavez; Janet Schechter

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 months 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.


Acta Cytologica | 1998

Compact cell blocks : Use for body fluids, fine needle aspirations and endometrial brush biopsies

Grace C.H. Yang; Livia Wan; Juliana Papellas; Jerry Waisman

OBJECTIVE To obtain an ideal cell block wherein the maximal number of cells are displayed within the smallest area on the block surface. STUDY DESIGN Cyto-Rich Red (AutoCyte, Inc., Elon College, North Carolina, U.S.A.) is added to fresh cellular sediment in a centrifuge tube at a ratio of 1:1. After two minutes, three to four drops of plasma and topical thrombin (5,000 U/10 mL) is added. The tube is then gently agitated for two minutes, until a gelatinous clot is obtained. The clot is then slid onto a lens tissue on top of paper towels. The lens tissue is folded once over the clot. By gently squeezing the excess fluid from it through the lens tissue into the paper towels, the clot is transformed into a flat, compact, densely cellular aggregate, which is painted with mercurochrome prior to fixation in formaldehyde. RESULTS From each of the 495 cases, including 250 body cavity fluids, 170 fine needle aspirates and 75 endometrial brush biopsies, processed with the above protocol, there was a compact cell block containing packed cells or tissue fragments in a clean background devoid of red blood cells. CONCLUSION The compact cell block is about 10-20% the size of a conventional cell block, yet more cells are on display, thus reducing the need for deeper cuts and screening time while increasing the efficiency of cytodiagnosis. The compact cell block technique is particularly helpful for endometrial brush biopsies.


American Journal of Pathology | 2002

Abnormal Uterine Bleeding during Progestin-Only Contraception May Result from Free Radical-Induced Alterations in Angiopoietin Expression

Graciela Krikun; Hilary O. D. Critchley; Frederick Schatz; Livia Wan; Rebeca Caze; Rebecca N. Baergen; Charles J. Lockwood

Abnormal uterine bleeding is the leading indication for discontinuation of long-term progestin-only contraceptives (LTPOCs). Histological sections of endometria from LTPOC-treated patients display abnormally enlarged blood vessels at bleeding sites. Paradoxically, a trend toward reduced endometrial perfusion in LTPOC users has been reported in these patients. We hypothesized that hypoxia/reperfusion-induced free radical production inhibits the expression of angiopoietin-1 (Ang-1), a vessel stabilizing factor, leaving unopposed the effects of endothelial Ang-2, a vessel-branching and permeability factor. Immunohistochemical studies confirmed selective decreases in stromal cell Ang-1 in LTPOC-exposed endometrium. To indirectly assess whether LTPOC enhances endometrial free radical production, immunostaining was conducted for the phosphorylated form of the stress-activated kinases SAPK/JNK and p38. These kinases were greatly increased in endometria from LTPOC-treated patients. Interestingly, the endothelial cells but not the stromal cells displayed enhanced immunostaining for the phosphorylated mitogen-activated kinase (pMAPK) after LTPOC treatment. To further examine the effects of progestin, hypoxia, and reactive oxygen species (ROS) on the regulation of Ang-1 and Ang-2 as well as the activation of MAPK, SAPK/JNK, and p38 by the relevant cell types, we conducted in vitro studies with cultured human endometrial stromal cells (HESCs) and human endometrial endothelial cells (HEECs). Cultures of HESCs were treated with vehicle control, estradiol (E(2)), or with medroxyprogesterone acetate +/- E(2) under hypoxic and normoxic conditions. Although medroxyprogesterone acetate but not E(2) increased Ang-1 expression, hypoxia greatly decreased Ang-1 protein and mRNA expression. In contrast, HESCs did not appear to express Ang-2 protein or mRNA. Conversely, cultured HEECs did not appear to express Ang-1, but expressed Ang-2, the levels of which were significantly increased by hypoxia. Hypoxia also induced the phosphorylation of SAPK/JNK and p38 in both cultured HESCs and HEECs. Moreover, ROS such as that observed after hypoxia/reperfusion resulted in the activation of SAPK/JNK and p38 in HESCs and HEECs and inhibited Ang-1 in cultured HESCs. These effects could be blocked by oxygen radical scavengers. Consistent with the in vivo studies, MAPK was activated after ROS treatment in HEECs but not in HESCs. Our findings suggest that LTPOC-induced endometrial bleeding occurs as a result of hypoxia/reperfusion-induced free radicals that directly damage vessels and alter the balance of Ang-1 and Ang-2 to produce the characteristic enlarged and permeable vessels that are prone to bleeding.


Contraception | 1997

Levonorgestrel concentrations during use of levonorgestrel rod (LNG ROD) implants

Irving Sivin; Pekka Lähteenmäki; Sirpa Ranta; Philip D. Darney; Cindy Klaisle; Livia Wan; Daniel R. Mishell; Maria Lacarra; Osborn Viegas; Prapas Bilhareus; Suporn Koetsawang; Manee Piya-Anant; Soledad Diaz; Margarita Pavez; Francisco Alvarez; Vivian Brache; Katherine D. LaGuardia; Harold A. Nash; Janet Stern

In a three-year randomized trial that included 398 women, blood samples were collected for the purpose of assaying levonorgestrel concentrations in women using a new two-rod contraceptive implant system or an earlier implant formulation, Norplant-2 implants. Sample collection was at 1, 3, 6, 9, and 12 months after placement and semiannually thereafter through three years. Resulting assays and analyses showed that levonorgestrel concentrations of each implant formulation decreased significantly with time after placement, with increasing body weight, and with ponderal index. In the third year, several measures indicated that concentrations of the contraceptive drug were higher in women using the LNG ROD implants than in users of the original formulation. No pregnancies occurred among women in either group in the three years. This study provides evidence that the minimum levonorgestrel concentration needed to protect against pregnancy is below 200 pg/ml, and possibly is below 175 pg/ml.


Obstetrics & Gynecology | 2007

Contraceptive Efficacy of a Novel Spermicidal Microbicide Used With a Diaphragm : A Randomized Controlled Trial

Kurt T. Barnhart; Michael J. Rosenberg; H. Trent Mackay; Diana L. Blithe; Jim Higgins; Terri Walsh; Livia Wan; Michael A. Thomas; Mitchell D. Creinin; Carolyn Westhoff; William D. Schlaff; David F. Archer; Charletta Ayers; Andrew M. Kaunitz; Sutapa Das; Thomas R. Moench

OBJECTIVE: Women need products that protect against both pregnancy and sexually transmitted infections, including human immunodeficiency virus (HIV). The acid buffering gel is a nondetergent spermicide that may provide this dual protection by reinforcing normal vaginal acidity to inactivate both sperm and acid-sensitive sexually transmitted pathogens. The objective of this study was to assess the gel’s contraceptive effects, safety, and acceptability. METHODS: We conducted a multicenter, randomized, double-masked, noninferiority study at 11 centers, comparing 621women who used an acid buffering gel plus diaphragm with 300 women who used a nonoxynol-9 spermicide plus diaphragm for 6 months. A double-masked study extension followed 234 women for an additional 6 months of use. RESULTS: The 6-month pregnancy rate per hundred women was 10.1% (95% confidence interval [CI] 7.1–13.1%) for acid buffering gel and 12.3 (95% CI 7.7–16.9) for nonoxynol-9 spermicide users. The difference in rates was –2.2% with a 95% CI –7.7 to 3.3%. Consistent and correct use 6-month pregnancy rates were 4.7% for acid buffering gel and 6.1% for nonoxynol-9 spermicide users, calculated from those cycles where diary entries indicated such use. Adverse events and acceptability were similar between the two groups. Pregnancy probabilities were similar between groups participating in the 12-month study extension. CONCLUSION: An acid buffering gel used with a diaphragm is a safe, acceptable contraceptive with efficacy comparable to that of a common commercial spermicide with diaphragm. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, www.ClinicalTrials.gov, NCT00065858 LEVEL OF EVIDENCE: I


Contraception | 2000

Prolonged effectiveness of Norplant® capsule implants: a 7-year study

Irving Sivin; Daniel R. Mishell; Soledad Diaz; Arijit Biswas; Francisco Alvarez; Philip D. Darney; Pentti Holma; Livia Wan; Vivian Brache; Orawan Kiriwat; Kamal el din Abdalla; Italo Campodonico; Samuel A. Pasquale; Margarita Pavez; Janet Schechter

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.


Contraception | 1998

Contraception with two levonorgestrel rod implants : A 5-year study in the United States and Dominican Republic

Irving Sivin; Francisco Alvarez; Daniel R. Mishell; Philip D. Darney; Livia Wan; Vivian Brache; Maria Lacarra; Cynthia Klaisle; Janet Stern

A 5-year trial of a two-rod contraceptive implant, which releases the progestin levonorgestrel (LNG rod), was conducted at four clinics with 594 women. Mean age and weight at admission were 25.5 years and 62.4 kg, respectively. Consent to continue through 5 years was sought and obtained when the 3-year cumulative pregnancy rate proved to be 0.8 per 100. No pregnancies occurred in the fourth or fifth years. The 5-year cumulative pregnancy rate was, therefore, 0.8 per 100 with an annual average pregnancy rate below 2 per 1000 women. Prolonged bleeding/spotting (8.2% of subjects) and irregular bleeding (5.6%) were the most frequently cited medical reasons for removal. Removals for headache (4.7%) and weight change (4.0%) were the next most frequent medical reasons. Between 1% and 2% of subjects during the 5-year trial sought removals for each of the following conditions: mood changes, lower abdominal pain, depression, or pain at the implant site. The mean annual continuation rate during the study was 77 per 100. Use per woman averaged 2.96 years. Mean removal time was 5.9 +/- 0.6 min. These data indicate that, for a 5-year period, the two LNG rod implants are equivalent to the six Norplant capsule implants with respect to safety and efficacy parameters, but permit easier and more rapid implant removal.

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Daniel R. Mishell

University of Southern California

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Francisco Alvarez

State University of Campinas

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Arijit Biswas

National University of Singapore

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