Related Experiment Video
Updated: Jul 18, 2026
12:34
Collection, Isolation, and Flow Cytometric Analysis of Human Endocervical Samples
Published on: July 6, 2014
Combined hormonal contraceptive trials: variable data collection and bleeding assessment methodologies influence
Daniel R Mishell1, John Guillebaud, Carolyn Westhoff
1Department of Obstetrics and Gynecology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA. mishell@usc.edu
Contraception
|December 13, 2006
Summary
Combined hormonal contraceptives (CHCs) have improved safety but increased unscheduled bleeding. Standardized data collection for bleeding events in CHC trials is needed for accurate patient counseling.
Area of Science:
- Reproductive Health
- Pharmacology
- Clinical Trials
Background:
- Oral hormonal contraceptives combining estrogen and progestin have evolved over 50 years, enhancing safety and convenience.
- Decreasing steroid doses in combined hormonal contraceptives (CHCs) correlate with increased unscheduled bleeding and spotting.
- Current clinical trials for CHCs lack standardized methods for collecting and analyzing bleeding and spotting data.
Purpose of the Study:
- To highlight the lack of standardized methods for collecting and analyzing bleeding and spotting data in combined hormonal contraceptive (CHC) trials.
- To emphasize the need for standardization to accurately assess cycle control and inform clinical practice.
Main Methods:
- The abstract does not detail specific methods but discusses the absence of standardized data collection techniques and analysis in CHC trials.
- It implies a review of current practices and regulatory approaches to bleeding and spotting events.
Main Results:
- Decreasing steroid doses in CHCs correlate with increased incidence of unscheduled bleeding and spotting.
- Current regulatory review of hormonal contraceptives does not include bleeding and spotting data in efficacy or safety categories.
Conclusions:
- Standardization of data collection and analysis for bleeding and spotting in CHC trials is critically needed.
- Clinicians must understand study-specific methods to accurately counsel patients on bleeding patterns with different CHC formulations.
Related Concept Videos
01:23Types of Biopharmaceutical Studies: Controlled and Non-Controlled Approaches
Biopharmaceutical studies constitute a vital field aiming to enhance drug delivery methods and refine therapeutic approaches, drawing upon diverse interdisciplinary knowledge. In research methodologies, the choice between controlled and non-controlled studies significantly influences the study's reliability and accuracy.
Non-controlled studies, commonly employed for initial exploration, lack a control group, rendering them susceptible to biases and external influences. In contrast, controlled...
Non-controlled studies, commonly employed for initial exploration, lack a control group, rendering them susceptible to biases and external influences. In contrast, controlled...
01:11Blinding
Blinding is a commonly used method of not telling participants which treatment a subject is receiving. Blinding is a critical part of a randomized control trial or RCT. It reduces the bias that affects the results. In an RCT, blinding is used in the form of a placebo. A placebo effect occurs when untreated subjects falsely believe they have received the treatment and report improved symptoms. A placebo or a dummy treatment is administered to subjects to negate the bias caused by such an effect.
02:07Blind Procedures
Ideally, the people who observe and record the children’s behavior are unaware of who was assigned to the experimental or control group, in order to control for experimenter bias. Experimenter bias refers to the possibility that a researcher’s expectations might skew the results of the study. Remember, conducting an experiment requires a lot of planning, and the people involved in the research project have a vested interest in supporting their hypotheses. If the observers knew which child was...
01:15Bioequivalence Experimental Study Designs: Repeated Measures, Cross-Over, Carry-Over, and Latin Square Designs
Bioequivalence experimental study designs play a pivotal role in testing the effectiveness of various treatments. Key among these are the repeated measures, cross-over, carry-over, and Latin square designs. In the repeated measures design, each subject receives all treatments, allowing for temporal comparisons. This type of design is useful in reducing variability but requires careful planning to avoid bias.The cross-over design, an economical method, involves sequential administration of...
01:16Clinical Trials
Clinical trials are prospective experimental studies conducted on humans to determine the safety and efficacy of treatments, drugs, diet methods, and medical devices. Using statistics in clinical trials enables researchers to derive reasonable and accurate conclusions from the collected data, allowing them to make wise decisions in uncertain situations. In medical research, statistical methods are crucial for preventing errors and bias.
There are four phases in a clinical trial. A phase one...
There are four phases in a clinical trial. A phase one...
01:22Hormonal Regulation of the Menstrual Cycle
The ovarian cycle regulates endometrial changes throughout a single menstrual cycle via the coordinated action of gonadotrophin-releasing hormone (GnRH) and gonadotrophins.
At puberty, GnRH begins a pulsatile release pattern, which triggers the anterior pituitary gland to secrete follicle-stimulating hormone (FSH) and luteinizing hormone (LH). The frequency and amplitude of GnRH pulses vary across the menstrual cycle, with faster pulses favoring LH release and slower pulses favoring FSH release.
At puberty, GnRH begins a pulsatile release pattern, which triggers the anterior pituitary gland to secrete follicle-stimulating hormone (FSH) and luteinizing hormone (LH). The frequency and amplitude of GnRH pulses vary across the menstrual cycle, with faster pulses favoring LH release and slower pulses favoring FSH release.