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Anita L Nelson

Publications and source records attributed to Anita L Nelson.

15 recordsLinked to original sources
PubMed2006

Combined hormonal contraceptive trials: variable data collection and bleeding assessment methodologies influence study outcomes and physician perception.

Initially approved for use in the United States nearly 50 years ago, oral hormonal contraceptives containing both estrogen and progestin have undergone steady improvements in safety and convenience. Concurrent with improvements in safety associated with decreasing doses of both steroids, there has been an increased incidence of unscheduled bleeding and spotting. There exist no standards regarding data collection techniques and methods, and reporting and analysis of bleeding and spotting events during combined hormonal contraceptive (CHC) trials. For the regulatory review of hormonal contraceptives, data regarding the incidence of bleeding and spotting events are not included in either of the traditional categories of efficacy and safety. Standardization of methods for collecting and analyzing data about cycle control in all clinical trials of CHCs is long overdue. Until such standards are developed and implemented, clinicians need to familiarize themselves with the techniques used in each study in order to provide correct information to their patients about the frequency of bleeding and spotting associated with different formulations and delivery systems.

Female↗
PubMed2006

Recommendations for standardization of data collection and analysis of bleeding in combined hormone contraceptive trials.

This is the second of a two-article series describing the outcomes of the Hormonal Contraceptives Trial Methodology Consensus Conference held in Philadelphia, PA, on September 23, 2005. The first manuscript, "Hormonal Contraceptive Trials: Variable Data Collection and Bleeding Assessment Methodologies Influence Study Outcome and Physician Perception," provided a description of methodologies applied in the US Food and Drug Administration medical officer's review of clinical trial data as contained in the Summary Basis of Approvals of New Drug Applications, results of the review and general conclusions. This manuscript provides recommendations regarding best practices in trial design, data collection and analysis regarding bleeding data in combined hormone contraception trials.

Contraceptives, Oral, Combined↗
PubMed2006

Recent use of condoms and emergency contraception by women who selected condoms as their contraceptive method.

OBJECTIVE: This study was undertaken to determine how consistently indigent, predominantly Hispanic women who had previously selected male condoms as their contraceptive method had used condoms and emergency contraception (EC) during the 2 weeks before their family planning clinic visit and reasons for any nonuse. STUDY DESIGN: Cross-sectional survey with no personal identifiers collected. RESULTS: Two hundred forty-eight women were surveyed. Overall, 43.8% of sexually active women reported inconsistent condom use during the prior 14 days. Only 39% of women who had not used condoms consistently used EC at least once. The most common reason for nonuse of both condoms (44%) and EC (41%) was that the woman did not perceive that she was at risk. CONCLUSION: Inconsistent use of condoms and low use of EC are very frequent, even in a short-time frame. Patients may be reluctant to volunteer to clinicians their real contraceptive choices. Risk taking occurs at high rates, even among couples provided ready and free access to male condoms and EC.

Adult↗
PubMed2005

Levonorgestrel implants enhanced the suppression of spermatogenesis by testosterone implants: comparison between Chinese and non-Chinese men.

CONTEXT: Previous male contraceptive studies showed that progestins enhance spermatogenesis suppression by androgens in men. OBJECTIVE: We compared the efficacy of spermatogenesis suppression by the combination of levonorgestrel (LNG) with testosterone (T) implants to that by T implants alone in two different ethnic groups. DESIGN: This was a randomized trial performed in two centers with two treatment groups. SETTINGS: The study was performed at the Academic Medical Center in the United States and the Research Institute in China. PARTICIPANTS: Forty non-Chinese and 40 Chinese healthy male volunteers were studied. INTERVENTIONS: Subjects were randomized to receive four LNG implants together with four T implants (inserted on d 1 and wk 15-18) vs. T implants alone for 30 wk. MAIN OUTCOME MEASURES: The primary end point compared the efficiency of suppression to severe oligozoospermia (1 x 10(6)/ml) by LNG plus T implants vs. that by T implants alone. The secondary end point examined differences in spermatogenesis suppression between Chinese and non-Chinese subjects. RESULTS: LNG plus T implants caused more suppression of spermatogenesis to severe oligozoospermia during the treatment period than T implants alone at both sites (P < 0.02). In Chinese men, severe oligozoospermia was achieved in more than 90% of the men in both treatment groups. Suppression to severe oligozoospermia was less in the non-Chinese men (59%) after T alone (P < 0.020); this difference disappeared with combined treatment (89%). T implant extrusion occurred in six men. Acne and increased hemoglobin were the most common adverse events. CONCLUSION: T implants resulted in more pronounced spermatogenesis suppression in Chinese men. Addition of LNG implants to T implants enhanced the suppression of spermatogenesis in the treatment period in both Chinese and non-Chinese men.

Adult↗
PubMed2005

Extended-cycle oral contraception: a new option for routine use.

Extended use of oral contraceptive (OC) pills can successfully suppress endometrial activity and prevent menstruation for several months. Given that missed menses in women not using hormonal contraception may be of medical concern, understanding how hormonal contraceptives eliminate these concerns is important for both patient and healthcare provider acceptance. OC withdrawal bleeding is an artificial, iatrogenic event, which results from the deliberate, periodic interruption of hormonal support of the endometrium. Historically, it was important to provide periodic bleeding to reassure OC efficacy, but today it is recognized that these bleeding episodes are medically unnecessary and cause patient discomfort and out-of-pocket expenses. Decades of experience with prolonged use of OCs have been accumulated for women with specific menstrual-related problems such as endometriosis, dysmenorrhea, and menstrual migraine headaches. Today there is a US FDA-approved product to routinely reduce the number of withdrawal periods. Clinical trials show that there is an initial increase in unscheduled bleeding and spotting days with extended-cycle OC use, but an absolute decrease in total days of bleeding and spotting from the first cycle of use. Over time, unscheduled bleeding and spotting decreases to rates found with the use of conventional-cycle regimens. Every woman who is interested in using OC pills should be offered the opportunity to choose how to use them, to determine if and when she will have withdrawal bleeding.

Adult↗
PubMed2004

Recent developments in hormone delivery systems.

Women who want safe, effective contraception have many more options than they did only a few years ago. Each option must be weighed carefully according to the needs and lifestyle of each particular woman. One method that provides long-term convenience with a side-effect profile that is comparable to that of oral contraceptives is the once-a-month injectable contraceptive containing 25 mg medroxyprogesterone acetate and 5 mg estradiol cypionate. Another option is the levonorgestrel-releasing intrauterine contraceptive system that offers pregnancy prevention for 5 years. Finally, hormonal implants that release low doses of progestins have been used for more than 30 years by a total of 10 million women, and easier-to-use implants will soon be available.

Contraceptive Agents, Female↗
PubMed2004

Effectiveness of the male latex condom: combined results for three popular condom brands used as controls in randomized clinical trials.

BACKGROUND: Although public health programs invest heavily in the male latex condom, its efficacy in preventing pregnancy and sexually transmitted disease has been based primarily on in vitro and retrospective studies. METHODS: We combine the results from two randomized, controlled contraceptive efficacy trials that used commercial latex condoms brands (Ramses Sensitol, LifeStyles, Trojan-Enz) in the control arms. Combining data from the two studies, we obtained longitudinal data covering 3526 menstrual cycles contributed by approximately 800 couples who used latex condoms exclusively for up to six menstrual cycles. Both trials also collected 3715 detailed breakage and slippage reports from the first five study condom uses. The second trial also tested 243 postcoital vaginal samples collected after the first study condom use for the presence of prostate-specific antigen (PSA) and spermatazoa. RESULTS: The combined clinical breakage rate for the first five condom uses was 0.4% for the three latex brands and the combined clinical slippage rate was 1.1%. The combined six-cycle typical-use pregnancy rate for the latex condoms was 7.0% (95% confidence interval 5.0-9.0). The combined six-cycle consistent-use pregnancy rate was 1.0% (95% confidence interval 0.0-2.1). PSA was detected in only 1.2% of postcoital vaginal samples collected after the first use of an intact study condom. There were no differences in performance or efficacy among the three latex brands tested. CONCLUSIONS: The male latex condoms rarely broke or slipped off during intercourse and provided high contraceptive efficacy, especially when used consistently. Risk of semen leakage from intact condoms was very low.

Adolescent↗
PubMed2003

Use of prostate-specific antigen (PSA) to measure semen exposure resulting from male condom failures: implications for contraceptive efficacy and the prevention of sexually transmitted disease.

Accurate measurement of semen exposure resulting from condom failures can refine public health messages and improve predictions of condom efficacy in preventing pregnancy and HIV transmission. Eight hundred and thirty couples enrolled in a condom efficacy study were asked to collect a baseline sample of ejaculate from the inside of the first study condom they used and to collect a postcoital vaginal sample whenever a study condom broke or slipped off during intercourse. All samples were quantitatively tested for prostate-specific antigen (PSA), a substance found only in human semen, using rocket immunoelectrophoresis, and inspected microscopically for presence of sperm. Sixty-eight baseline ejaculate samples collected from the inside of the first study condom by couples who subsequently experienced a condom failure averaged 13.4 microg PSA per swab and 79% of the samples averaged one or more sperm per high power field (hpf). Seventy-nine postcoital vaginal samples obtained after a condom break averaged 5.7 microg PSA per swab and only 38% averaged one or more sperm per hpf. The PSA results indicated a 50% reduction in semen exposure compared to baseline levels (p = 0.0001). Seventeen samples obtained after a condom slip-off averaged 2.5 microg PSA per swab and none of the samples averaged one or more sperm per hpf. The PSA results indicated an 80% reduction in semen exposure compared to baseline levels (p = 0.0001). Our results suggest that even condoms that fail reduce the risk of pregnancy and the transmission of sexually transmitted disease compared to unprotected intercourse. We also used PSA results to adjust a model designed to predict consistent-use pregnancy rates from condom breakage and slippage data.

Coitus↗
PubMed2003

Ambulatory diagnosis and medical management of ectopic pregnancy in a public teaching hospital serving indigent women.

OBJECTIVE: The study was undertaken to evaluate the outcomes of indigent women with possible ectopic pregnancy who were cared for in a public teaching hospital outpatient clinic by multiple residents. STUDY DESIGN: Retrospective review of patients seen in the Obstetric-Gynecologic Urgent Care Center at Harbor-UCLA Medical Center from September 1, 2000, through August 30, 2001, was performed. RESULTS: Of the 243 women being evaluated for possible ectopic pregnancy, 4 required surgical intervention during their diagnostic workup and 58 were lost to follow-up. Of the 31 women given methotrexate therapy, 25 successfully completed therapy, 2 required surgery, and 4 were lost to follow-up. Substantial investment was needed to contact patients who missed appointments. CONCLUSION: It is feasible to manage women with possible ectopic pregnancies on an ambulatory basis in a public teaching hospital, but close oversight is needed and both staff and patients must commit to significant follow-up. Local protocols can be modified to reduce the numbers of visits required.

Adolescent↗
PubMed2002

Impact of early postpartum administration of progestin-only hormonal contraceptives compared with nonhormonal contraceptives on short-term breast-feeding patterns.

OBJECTIVE: The purpose of this study was to identify the impact on breast-feeding patterns of early postpartum initiation of progestin-only birth control methods compared with nonhormonal methods. STUDY DESIGN: A prospective, nonrandomized trial was performed comparing progestin-only contraceptive methods administered before hospital discharge with nonhormonal methods on breast-feeding continuation rates, exclusive breast-feeding, and supplementation at 2, 4, and 6 weeks after delivery. RESULTS: Three hundred nineteen women provided complete data until hospital discharge. The hormonal group had higher risk factors for not breast-feeding, but there was no difference among any of the subgroups in breast-feeding continuation rates except at week 4. Supplementation or perception of insufficient milk production did not differ between groups. By week 6, 23.5% of women discontinued breast-feeding, and 64.5% of those breast-feeding were supplementing. CONCLUSION: This study demonstrates that there is no detectable adverse impact on breast-feeding attributable to progestin-only contraceptive methods initiated within the first 3 days post partum.

Breast Feeding↗
PubMed2002

The importance of patient and healthcare provider perceptions in the evaluation of imiquimod and other prior treatments for anogenital warts.

The experience and satisfaction of healthcare providers and patients were assessed for various treatment options for anogenital warts. Patients were asked about their immediate experience with imiquimod cream 5% and - for patients with recurrent warts - their recall of prior experiences with other treatment options. Surveys were completed pre-study by 744 patients and post-study by 399 patients and 69 healthcare providers; obstetricians/gynaecologists were the predominant (25 of 69; 36%) specialty. Approximately two-thirds (475 of 744; 64%) of patients in the pre-study survey had previously been treated for anogenital warts. Patients with recurrent warts were generally dissatisfied with prior therapies. In post-study surveys, imiquimod received favourable ratings from patients with recurrent warts and from patients treated for the first time. Healthcare providers rated imiquimod favourably for overall acceptance, convenience, and compliance. Perceptions of various treatments for anogenital warts by patients and healthcare providers can vary considerably. Therefore, comparative studies should include assessments of these perceptions to gain a full understanding of the relative merits of the therapies under investigation.

Administration, Topical↗
PubMedDate not supplied

Evaluation of the efficacy of a nonlatex condom: results from a randomized, controlled clinical trial.

CONTEXT: To reduce unintended pregnancy and HIV infection, it is critical to develop reliable male condoms that will attract consumers who reject conventional latex condoms. METHODS: In a prospective clinical trial conducted in 1998-2000, 830 monogamous couples were randomized in equal numbers to use either a nonlatex condom or a commercial natural latex condom for six months as their only method of birth control. Couples completed detailed reports for the first five condom uses and recorded intercourse and condom use in coital diaries. Pregnancy rates associated with typical and consistent condom use were calculated using life-table analysis. Rates of clinical failure (condom breakage or slippage) were determined for the first five condom uses. RESULTS: During the first five uses, the nonlatex condom had a higher frequency of breakage or slippage during intercourse or withdrawal (4.0%) than latex condoms (1.3%); the breakage rate for the nonlatex condom was about eight times that of latex condoms. The six-cycle typical-use pregnancy rate did not differ significantly between users of nonlatex (10.8%) and latex condoms (6.4%). The six-cycle consistent-use pregnancy rate was higher for nonlatex condom users than for latex condom users (4.9% vs. 1.0%). CONCLUSIONS: The data present strong indirect support for public health messages that promote the use of latex condoms and, for individuals who cannot or are unwilling to use latex condoms, the use of nonlatex condoms for prevention of pregnancy and disease.

Adult↗
PubMedDate not supplied

Postmenopausal hormone therapy and breast cancer: where do we stand?

The relationship between clinically apparent breast cancer and postmenopausal hormone therapy has been clarified in the last few years. It is clear that long-term, current users are at increased risk. Most women using HT for short-term treatment of vasomotor symptoms will not face measurable increases in their risk for breast cancer. That risk returns to baseline a few years after discontinuation of hormones. Breast cancer detection may be delayed by HT use; temporary interruption of HT prior to mammography may maintain sensitivity of that screening test. This article explores the literature as it has evolved from observational studies to prospective randomized clinical trials to see if a unified understanding of the epidemiology, biology and clinical significance of the potential risk temporally associated with prolonged HT use can be developed.

Breast Neoplasms↗