Most people who get pregnant develop a condition called morning sickness; some, like Catherine, Princess of Wales, and actress Amy Schumer, have such severe forms that they need to be hospitalized, and some women even die from it.
Scientists have searched for years to understand the cause in the hopes that they may one day find a cure for it.
A study published this week in the journal Nature suggests that some pregnant people are particularly sensitive to a hormone called GDF15. It’s produced at low levels throughout the body, but a pregnant person gets another strong dose from the growing fetus, and that can trigger nausea and vomiting. Studies done with cancer patients have found that when the body produces too much GDF15, it can lead to chronic nausea and weight loss.
A 2018 study found a link between the gene that controls GDF15 and nausea and vomiting in pregnancy in 53,000 women. The new paper builds on that work and establishes this connection between the hormone and the condition by looking at the issue from a variety of perspectives, including genetic information and data from a new test that can determine what hormones are in a pregnant person’s blood and at what level, in addition to studies in mice and in the lab.
The researchers found that levels of GDF15 rise in the first 12 weeks of pregnancy. The higher the levels of the hormone from the fetus and the more sensitive the pregnant person was to the hormone, the sicker she got. When the fetus produces less GDF15, the risk of getting sick seems to be lower. Her exposure to it before pregnancy also can be a factor.
The scientists also looked at research that said people who had a particular inherited blood disorder and who had high levels of the hormone in their body before they became pregnant almost never got sick during pregnancy. They also saw the inverse: Those who have a rare genetic variant that causes them to have low levels of GDF15 are at a much higher risk of hyperemesis gravidarum. The authors also found that when mice were exposed to high levels of GDF15, they lost their appetite, suggesting they were experiencing nausea. When they were treated with a long-acting form of the hormone, they had a regular appetite.
About 70% to 80% of people who get pregnant get what’s commonly called “morning sickness,” although pregnant people can feel nauseated and vomit any time of day.
People with morning sickness are sometimes told to take anti-nausea medications and advised to get lots of rest, drink plenty of fluids and avoid nausea triggers like smells. But knowing what causes any form of morning sickness, severe or mild, could help scientists find a cure — or at least a better way to relieve symptoms.
Doctors can prescribe anti-vomiting medications and vitamin B1 to women with HG, which can be helpful to protect the pregnant person’s heart and brain and to support the baby’s development.
Studies now underway are looking at ways to prevent the hormone-induced stomach upset in cancer patients, but none have involved pregnant people.
SOURCE:CNN