A new study from Iran found that two rare birth defects - atrioventricular septal defects (AVSD) and cleft palate - occurred more often in infants whose mothers received a COVID-19 vaccine during the first 12 weeks of pregnancy compared with mothers who received the vaccine later or not at all.

Unlike studies conducted in the U.S. and Europe, none of the women in the Iranian study received mRNA vaccines — however, all of the COVID-19 vaccines available in Iran contain 0.25-0.50 milligrams of aluminum adjuvant, Children's Health Defense Senior Research Scientist Karl Jablonowski told The Defender.

Shots containing aluminum are not typically recommended for pregnant women in their first trimester, Jablonowski said.