Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Teratogenicity01:07

Teratogenicity

The ability of a drug to produce structural deformations and functional abnormalities in the developing embryo or the fetus is called teratogenicity, and the drug producing this effect is known as a teratogen. Teratogenic effects include stillbirth, miscarriage, intrauterine growth restriction, and neurocognitive delay. A teratogen may affect the embryo at different stages of development, which is important in determining the type and extent of the damage. During blastocyst formation, the early...
Therapeutic Drug Monitoring: Affecting Factors01:29

Therapeutic Drug Monitoring: Affecting Factors

Therapeutic Drug Monitoring (TDM) is the clinical practice of measuring specific drug levels in a patient's blood or body tissues to manage and optimize therapy. TDM is crucial for drugs with narrow therapeutic windows, like warfarin and phenytoin, where incorrect doses can lead to treatment failure or severe side effects. This monitoring ensures the dosage administered is within a safe and effective range. The factors affecting therapeutic drug monitoring include:Patient-Specific Factors:a.
Pharmacogenetics of Phase II Enzymes: N-acetyltransferase, Thiopurine S-methyltransferase, UDP-glucuronosyltransferase01:27

Pharmacogenetics of Phase II Enzymes: N-acetyltransferase, Thiopurine S-methyltransferase, UDP-glucuronosyltransferase

Phase II biotransformation reactions are essential for detoxifying and eliminating xenobiotics, including many pharmaceutical compounds. These reactions typically involve conjugation, the covalent attachment of polar endogenous groups such as glucuronic acid, sulfate, methyl, or acetyl moieties to functional groups introduced during Phase I metabolism. The resulting conjugates are more water-soluble, enabling efficient renal or biliary excretion.The major classes of Phase II enzymes include...
Phase II Reactions: Methylation Reactions01:17

Phase II Reactions: Methylation Reactions

Methylation is a phase II biotransformation process involving the attachment of a methyl group to a substrate. Enzymes known as methyltransferases orchestrate this reaction.
The mechanism of methylation unfolds in two stages. The first stage sees a methyltransferase enzyme facilitating the transfer of a methyl group from S-adenosylmethionine (SAM) to the substrate, forming S-adenosylhomocysteine (SAH). The second stage involves further metabolism of SAH into homocysteine, which can be recycled...
Pharmacogenetics of Drug Targets: β₂-Adrenergic Receptors, Apo E, Thymidylate Synthase01:11

Pharmacogenetics of Drug Targets: β₂-Adrenergic Receptors, Apo E, Thymidylate Synthase

Genetic polymorphisms in drug targets have emerged as critical determinants of interindividual variability in drug response and toxicity. Pharmacogenomic investigations increasingly focus on identifying these variations to personalize and optimize therapeutic interventions. A drug target may be a receptor, enzyme, or signaling protein involved in pharmacologic responses or disease-related pathways. While early pharmacogenetic studies focused primarily on drug metabolism, current research...
Mutagenicity and Carcinogenicity01:25

Mutagenicity and Carcinogenicity

Mutagenicity and carcinogenicity refer to the ability of drugs to cause genetic defects and induce cancer, respectively. The International Agency for Research on Cancer (IARC) classifies agents into four groups based on their carcinogenic potential. Group 1 agents are known human carcinogens; group 2A agents are probably carcinogenic to humans; group 3 agents lack data to support their role in carcinogenesis; and group 4 includes agents for which data support that they are not likely to be...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

The effects of menopausal hormone therapy on cardiovascular disease, cancer, cognition and depression in younger women: A systematic review.

JRSM open·2026
Same author

Teratogen Update: Fever in Pregnancy.

Birth defects research·2026
Same author

Comprehensive review of octocrylene toxicology data and human exposure assessment for personal care products.

Critical reviews in toxicology·2026
Same author

Identification and Prenatal Evaluation of Suspected Congenital Cataracts: Three Very Different Cases.

Journal of clinical ultrasound : JCU·2025
Same author

Comprehensive review of ensulizole toxicology data and human exposure assessment for personal care products.

Critical reviews in toxicology·2025
Same author

Comprehensive review of avobenzone (butyl methoxydibenzoylmethane) toxicology data and human exposure assessment for personal care products.

Critical reviews in toxicology·2025
Same journal

Association between antibiotic use among pregnant women with urinary tract infections in the first trimester and birth defects, National Birth Defects Prevention Study 1997 to 2011.

Birth defects research. Part A, Clinical and molecular teratology·2016
Same journal

Evaluation of the Western Australian Register of Developmental Anomalies: Thirty-five years of surveillance.

Birth defects research. Part A, Clinical and molecular teratology·2016
Same journal

A quality assessment of reporting sources for microcephaly in Utah, 2003 to 2013.

Birth defects research. Part A, Clinical and molecular teratology·2016
Same journal

Editorial brain malformation surveillance in the Zika era.

Birth defects research. Part A, Clinical and molecular teratology·2016
Same journal

Characterizing facial features in individuals with craniofacial microsomia: A systematic approach for clinical research.

Birth defects research. Part A, Clinical and molecular teratology·2016
Same journal

Population-based microcephaly surveillance in the United States, 2009 to 2013: An analysis of potential sources of variation.

Birth defects research. Part A, Clinical and molecular teratology·2016
See all related articles

Related Experiment Video

Updated: May 23, 2026

Comprehensive Evaluation of the Effectiveness and Safety of Placenta-Targeted Drug Delivery Using Three Complementary Methods
09:04

Comprehensive Evaluation of the Effectiveness and Safety of Placenta-Targeted Drug Delivery Using Three Complementary Methods

Published on: September 10, 2018

Teratogen update: methotrexate.

Sara C Hyoun1, Sarah G Običan, Anthony R Scialli

  • 1George Washington University, School of Medicine and Health Sciences, Washington, DC, USA.

Birth Defects Research. Part A, Clinical and Molecular Teratology
|March 22, 2012
PubMed
Summary
This summary is machine-generated.

Methotrexate exposure during pregnancy, especially when an intrauterine pregnancy is misdiagnosed as ectopic, can lead to a distinct methotrexate embryopathy. This syndrome includes growth deficiencies and malformations, with early exposures potentially causing unique abnormalities.

More Related Videos

Developmental Toxicity Assay Based on Real-Time Monitoring of Fibroblast Growth Factor Signal Disruption in Human Induced Pluripotent Stem Cells
05:45

Developmental Toxicity Assay Based on Real-Time Monitoring of Fibroblast Growth Factor Signal Disruption in Human Induced Pluripotent Stem Cells

Published on: October 10, 2025

Related Experiment Videos

Last Updated: May 23, 2026

Comprehensive Evaluation of the Effectiveness and Safety of Placenta-Targeted Drug Delivery Using Three Complementary Methods
09:04

Comprehensive Evaluation of the Effectiveness and Safety of Placenta-Targeted Drug Delivery Using Three Complementary Methods

Published on: September 10, 2018

Developmental Toxicity Assay Based on Real-Time Monitoring of Fibroblast Growth Factor Signal Disruption in Human Induced Pluripotent Stem Cells
05:45

Developmental Toxicity Assay Based on Real-Time Monitoring of Fibroblast Growth Factor Signal Disruption in Human Induced Pluripotent Stem Cells

Published on: October 10, 2025

Area of Science:

  • Teratology and Developmental Toxicology
  • Pharmacology and Drug Safety
  • Obstetrics and Gynecology

Background:

  • Methotrexate (MTX) is a folic acid antagonist used for various conditions, including ectopic pregnancy treatment.
  • Misdiagnosis of intrauterine pregnancy as ectopic can lead to unintended MTX exposure.
  • Animal studies and human case reports link MTX exposure to adverse pregnancy outcomes.

Purpose of the Study:

  • To review and define the spectrum of anomalies associated with methotrexate embryopathy.
  • To investigate potential differences between early and later gestational MTX exposure.
  • To highlight the risks of MTX exposure in pregnancy due to misdiagnosis.

Main Methods:

  • Review of experimental animal studies on MTX teratogenicity.
  • Analysis of human case reports detailing MTX exposure during pregnancy.
  • Disproportionality analysis of MTX and aminopterin case reports.

Main Results:

  • Animal studies show MTX causes embryo death and structural malformations (e.g., in rabbits).
  • Human case reports describe methotrexate embryopathy with features like growth deficiency, microcephaly, and limb abnormalities.
  • Early exposure (before 6 weeks) may be linked to distinct anomalies, including Tetralogy of Fallot.

Conclusions:

  • Methotrexate exposure during pregnancy can cause a range of developmental abnormalities, termed methotrexate embryopathy.
  • Distinct syndromes may arise from early versus later gestational exposure.
  • Further data is needed to fully characterize methotrexate embryopathy and early exposure syndromes.