The trial will enroll 1,000 females and study them for 21 months, the announcement said.
The study population will include women who have received the Moderna vaccine during the 28 days prior to their last menstrual period or at any time during their pregnancy.
"The main goal of this study is to evaluate the outcomes of pregnancy in females exposed to the Moderna COVID-19 vaccine (mRNA-1273) during pregnancy," a brief summary said.
The study, which is not yet recruiting, according to the post, is estimated to start on July 22.
It will focus on infant and pregnancy outcomes, pregnancy complications and suspected major and minor congenital malformations.
Fox Business, which reported on the clinical trial, noted Moderna shares rose 3% Monday.
"If you are pregnant, you can receive a COVID-19 vaccine," the Centers for Disease Control and Prevention's website states. "Getting a COVID-19 vaccine during pregnancy can protect you from severe illness from COVID-19. If you have questions about getting vaccinated, a conversation with your healthcare provider might help, but is not required for vaccination."
The CDC and the Federal Drug Administration have collected preliminary data from safety monitoring systems that "did not identify any safety concerns for pregnant people who were vaccinated or for their babies," according to the CDC website.
Pregnant people were not specifically included in clinical trials before the FDA granted Emergency Use Authorization of COVID-19 vaccine, "due to historical restrictions on including those who are pregnant in clinical trials," the University of Chicago Medicine previously noted.
Still, "in certain situations, it may be scientifically and ethically appropriate to include pregnant women in a clinical trial," according to the FDA.
Animal studies involving Moderna, Pfizer-BioNTech, or Johnson & Johnson/Janssen COVID-19 vaccine prior to or during pregnancy "found no safety concerns," the CDC noted.