A single hormone is mostly responsible for the nausea and vomiting that characterise the first trimester of pregnancy, according to a study published on Wednesday in the journal Nature. The finding, according to researchers, may result in improved morning sickness therapies, especially those for extremely rare and potentially fatal instances.
The hormone known as GDF15 has been linked to previous research, which the study validates. The researchers discovered that a woman’s prenatal exposure to hormone and the quantity of it in her blood throughout pregnancy determine how severe her symptoms are.
During the first trimester, nausea and vomiting affect more than two thirds of pregnant women. Additionally, morning sickness, a disorder that causes persistent nausea and vomiting throughout the whole pregnancy, accounts for about 2% of hospital admissions among pregnant women. Dehydration, weight loss, and malnutrition are possible outcomes of the illness. Additionally, it raises the chance of blood clots, preterm birth, and preeclampsia, endangering both the mother’s and the foetus’ lives.
Experts noted that morning sickness is the primary cause of hospitalisation during the early stages of pregnancy, but clinicians frequently ignore it, writing off its extreme symptoms as psychological, maybe because nausea and vomiting are so common during pregnancy. Despite the fact that the ailment is still poorly understood, celebrities like Amy Schumer and Kate Middleton have helped to bring attention to it in recent years by sharing their own stories.
Geneticist Marlena Fejzo, a co-author of the new study and geneticist at the University of Southern California Keck School of Medicine, stated, “I’ve been working on this for 20 years, and yet there are still reports of women dying from this and women being mistreated.”
She has direct experience with the agony of the illness. Fejzo was unable to eat or drink anything in 1999 during her second pregnancy without throwing up. She lost weight so quickly that she was unable to walk or stand. Her physician was contemptuous, implying that she was making up her ailments to attract attention. After being admitted to the hospital, she miscarried at 15 weeks.
Fejzo claimed that despite her request, the National Institutes of Health refused to provide funding for a genetic study on morning sickness. Not to be defeated, she convinced the well-known genetic testing business 23andMe to add questions regarding hyperemesis to questionnaires that were sent to tens of thousands of consumers. She released a report in 2018 demonstrating that patients with morning sickness typically carried a mutation in the GDF15 gene.
Chemicals called hormones carry information throughout the body. Many tissues secrete GDF15 in reaction to stressors like infections. Furthermore, the hormone’s signal is very specific: Hormone receptors are concentrated in the area of the brain linked to nausea and vomiting.
Fejzo and associates at the University of Cambridge in England examined the genetic risk factors for morning sickness and evaluated the hormone in the blood of expectant mothers in the latest study.
The GDF15 levels in pregnant women having morning sickness were found to be much higher than in those who did not experience any symptoms, the researchers discovered.
However, the woman’s sensitivity to the hormone and her exposure to it prior to becoming pregnant appear to determine the hormone’s effect. For instance, the researchers discovered that pregnant women in Sri Lanka with a rare blood condition that results in persistently elevated levels of GDF15 hardly ever suffered nausea or vomiting.
“It totally eliminated all of the nausea.” The University of Cambridge endocrinologist who oversaw the research, Dr. Stephen O’Rahilly, stated, “They pretty much have next to zero symptoms in their pregnancies.”
Research in 60 Seconds: extreme morning sickness & GDF15
According to O’Rahilly’s theory, women who are exposed to GDF15 for an extended period of time prior to becoming pregnant may be less susceptible to the abrupt spike in hormones that the growing foetus causes.
The hormone was given in little doses to certain mice in laboratory tests. The mice demonstrated a strong desensitisation effect when they were given a much higher dose three days later. They did not reduce their appetite as much as the animals who had not received the previous dose.
Experts stated that the results provide hope for more effective therapies for morning sickness. If clinical trials prove that the pharmaceuticals are safe to take during pregnancy, patients suffering from morning sickness may eventually be able to take medication to prevent the hormone’s effects in the brain. Trials involving cancer patients experiencing vomiting and appetite loss due to GDF15 are testing these drugs.
In fact, the illness might even be avoidable. Low doses of the hormone may be given to women who are at risk, such as those who had severe nausea and vomiting during a prior pregnancy, before they get pregnant. (Metformin, a medication for diabetes, raises GDF15 levels and is being recommended to some people to help with conception.)
According to Rachel Freathy, a geneticist at the University of Exeter who was not involved in the study, the new discovery is significant since it provides genetic evidence of a causal association between GDF15 and the illness. According to her, that will aid in the condition’s increased recognition.
According to Freathy, “many people kind of assume that women should just be able to cope with this.” “There will be more belief that this is a real thing rather than something in somebody’s head,” she said, citing the biological reason.
Also Read: 5 Tips For A Happy, Healthy Pregnancy
