Embryo Project Encyclopedia Articles

In 1986, Vern L. Katz, Deborah J. Dotters, and William Droegemueller published “Perimortem Cesarean Delivery,” an article in which they developed the Four Minute Rule for perimortem cesarean sections. The Four Minute Rule states that if a pregnant woman’s heart stops beating, physicians should begin an operation to deliver the fetus within four minutes and aim to have the fetus delivered within five minutes of cardiac arrest. Although cardiac arrest during pregnancy is uncommon, it can happen when pregnant women experience trauma, blood clots, infection, or have preexisting heart conditions. In the article, the authors emphasize how the Four Minute Rule increased maternal and fetal survival rates and decreased cases of severe fetal brain damage. The article “Perimortem Cesarean Delivery” was the first article to present the Four Minute Rule, which has influenced international guidelines and become the standard for maternal resuscitation and fetal survival in emergency medicine, operating rooms, and many other aspects of medical practice.

Nuclear magnetic resonance imaging (MRI) is a technique to create a three-dimensional image of a fetus. Doctors often use MRIs to image a fetuses after an ultrasound has detected an, or has been inconclusive about an, abnormality. In 1983 researchers in Scotland first used MRI to visualize a fetus. MRIs showed a greater level of fetal detail than ultrasound images, and researchers recognized the relevance of this technique as a means to gather information about fetal development and growth. Researchers later used the technology to take measurements of the uterus, placenta, amniotic fluid, and fetus during the first trimester of pregnancy. MRI provided doctors with a non-invasive method to diagnose and treat fetal abnormalities and maternal conditions such as pre-eclampsia.