Related Experiment Video
Updated: Feb 22, 2026
04:53
A Clinical Trial Assessing the Safety, Efficacy, and Delivery of Olive-Oil-Based Three-Chamber Bags for Parenteral Nutrition
Published on: September 20, 2019
11.4K
Randomized Trial Comparing Two Algorithms for Levothyroxine Dose Adjustment in Pregnant Women With Primary
Shannon D Sullivan1,2, Erin Downs2, Geanina Popoveniuc2
1Division of Metabolism and Endocrine Products, US Food and Drug Administration, Center for Drug Evaluation and Research, Office of New Drugs, Silver Spring, Maryland 20993.
The Journal of Clinical Endocrinology and Metabolism
|September 16, 2017
Summary
An ongoing approach to adjusting levothyroxine (LT4) dosage is as effective as empiric increases for managing thyroid stimulating hormone (TSH) in pregnant women. This study compared two methods, finding similar outcomes in maintaining optimal TSH levels during pregnancy.
Area of Science:
- Endocrinology
- Reproductive Medicine
- Pharmacology
Background:
- Maternal thyroid hormone regulation is vital for pregnancy success.
- No established guidelines exist for levothyroxine (LT4) dose adjustments during pregnancy.
Purpose of the Study:
- To compare two distinct levothyroxine (LT4) dose-adjustment algorithms in pregnant women with hypothyroidism.
- To evaluate the efficacy of different LT4 management strategies in maintaining target thyroid stimulating hormone (TSH) levels.
Main Methods:
- Thirty-three hypothyroid women (38 pregnancies) were randomized into two groups: Group 1 (G1) with empiric weekly LT4 dose increases and Group 2 (G2) with ongoing, TSH-guided daily LT4 adjustments.
- Thyroid stimulating hormone (TSH) levels were monitored bi-weekly in the first two trimesters and monthly in the third trimester.
Main Results:
- Eighty-one percent of TSH values were within target ranges in the ongoing adjustment group (G2) versus 75% in the empiric group (G1) (P=0.09).
- Both groups required a similar number of LT4 dose adjustments.
- Group 1 (empiric) showed a higher incidence of suppressed TSH (<0.1 mIU/L) in the first trimester.
Conclusions:
- An ongoing, TSH-guided approach to LT4 dose adjustment is as effective as empiric dose increases for managing hypothyroidism in pregnancy.
- These findings support individualized, TSH-monitored LT4 management strategies during gestation.
Related Concept Videos
01:20Bioequivalence Experimental Study Designs: Completely Randomized and Randomized Block Designs
295
Body:Bioequivalence experimental study designs are crucial methodologies used in evaluating and comparing the bioavailability of different drug products. These designs are categorized into various types: completely randomized, randomized block, repeated measures, cross and carry-over, and Latin square designs.Completely randomized designs involve randomly allocating treatments to all subjects participating in the experiment. This allocation is achieved by assigning unique random numbers to...
295
01:28Dosage Regimens: Designs and Approaches
367
Designing a dosage regimen, which refers to the manner of drug administration, is a complex process involving the selection of drug dose, route, and frequency. This process is underpinned by pharmacokinetic parameters derived from tests and population averages. These parameters are then tailored to patient-specific variables such as diagnosis, demographics, and allergy status. Once therapy commences, therapeutic response monitoring is critical and achieved through clinical and physical...
367
01:29Drug Dosing: Infants and Children
371
Pediatric patient dosages diverge from adults due to disparities in body surface area, total body water, and extracellular fluid per kilogram of body weight. The dosing regimen considers the variations in pharmacokinetics and pharmacology across distinct age groups, encompassing preterm newborns, infants, young children, older children, and adolescents. Calculation of pediatric patient doses is predicated on determining body surface area, which exhibits a superior correlation with the child's...
371
01:21Drug Dosing: Obese Patients
303
In the United States, obesity is a prominent concern. It is linked to heightened mortality rates due to increased occurrences of conditions such as hypertension, atherosclerosis, coronary artery disease, and diabetes compared to nonobese individuals. A patient is classified as obese if their actual body weight surpasses the ideal or desirable body weight by 20%, based on Metropolitan Life Insurance Company data. Ideal body weights consider average weights and heights for males and females...
303
01:25Determination of Multiple Dosing Parameters: Loading and Maintenance Doses
284
A loading dose is an essential pharmacological strategy to rapidly achieve the target plasma drug concentration necessary for an immediate therapeutic effect. This approach is especially critical for drugs characterized by slow absorption or extended half-lives, where delaying therapeutic plasma levels could compromise treatment outcomes. By administering a loading dose, clinicians ensure a prompt onset of drug action, even for agents with complex pharmacokinetic profiles.Achieving steady-state...
284
01:13Randomized Experiments
9.1K
The randomization process involves assigning study participants randomly to experimental or control groups based on their probability of being equally assigned. Randomization is meant to eliminate selection bias and balance known and unknown confounding factors so that the control group is similar to the treatment group as much as possible. A computer program and a random number generator can be used to assign participants to groups in a way that minimizes bias.
Simple randomization
Simple...
Simple randomization
Simple...
9.1K