Researchers have identified a possible cause of some preterm births and a potential way to prevent them. A separate study suggests the way people consume cannabis may affect the amount of anaesthesia needed during medical procedures.
Immune-System Catalyst for Preterm Labour Identified
Researchers have identified antibodies in pregnancy that appear to play a role in triggering preterm labour, according to data from a study of more than 2,000 pregnant women.
In the study published in Nature Immunology, researchers found the antibodies were present in higher levels and appeared earlier in pregnancy in women who went on to give birth before 37 weeks' gestation compared with those who delivered their babies at term.
The antibodies target a protein called IL-1RA that blocks a molecule called IL-1-beta, which drives a type of inflammation known to trigger uterine contractions.
By neutralising IL-1RA, the antibodies allow IL-1-beta and the inflammation it causes to rise unchecked, which could explain why some women go into labour too early, the researchers said.
When they injected IL-1RA antibodies into pregnant mice, IL-1-beta levels rose and placentas showed signs of damage also seen in human preterm deliveries.
A synthetic form of IL-1RA already exists to treat inflammatory conditions such as rheumatoid arthritis. Researchers said Swedish Orphan Biovitrum's drug Kineret might also help prevent preterm births by suppressing IL-1, inflammation and premature uterine contractions.
The researchers cautioned that the antibodies were found in only a fraction of preterm births, suggesting there are many other causes.
Still, the discovery of an immune signal “pointing us toward why some pregnancies go wrong is an exciting result,” senior study author Joe DeRisi of UCSF said in a statement.
Cannabis Impact on Sedation Varies by Product Type
Cannabis use can affect the amount of anaesthesia and sedation needed during medical procedures, but the impact may vary by consumption method, a small study suggests.
Patients who smoke or vape cannabis may need more anaesthesia than those who use edibles or do not use cannabis, researchers reported at the Anesthesiology 2026 meeting of the American Society of Anesthesiologists in San Diego.
They reviewed data from 280 colonoscopies and upper endoscopies involving 264 patients: 217 non-users of cannabis, 38 who reported inhaled use and nine who consumed cannabis gummies or other edibles.
Across all cannabis users, researchers found no significant difference in the initial dose of the anaesthetic propofol.
However, the average initial dose was 138.7mg among non-users, 168.5mg among those who inhaled cannabis and 114.2mg among those who consumed it orally.
The findings suggest that people who smoke or vape cannabis may need more propofol, while those using edibles did not show the same pattern. Researchers cautioned that the edible group was small.
The findings may help explain conflicting results in earlier studies, which often grouped cannabis users together without distinguishing how they consumed it.
The difference was most pronounced during upper endoscopy, when a camera-equipped tube is passed through the mouth, throat and upper airway. No meaningful differences were observed during colonoscopies.
Inhaled and edible cannabis products are processed differently by the body, the researchers noted. Smoking or vaping delivers THC, the main psychoactive component, through the lungs. Regular inhalation may also irritate the upper airway, potentially requiring deeper anaesthesia to help patients tolerate the endoscope.
“The most important message for patients is to be honest with their anesthaesiologist about cannabis, including how they use it — smoking, vaping or edible products — how often they use it and when they last used it,” study leader Dr Basavana Goudra of Sidney Kimmel Medical College in Philadelphia said in a statement.
“For physicians, simply asking, ‘Do you use cannabis?’ may no longer be sufficient.”