Category: Obstetrics & Gynaecology

Categories : Cardiovascular Disease Obstetrics & GynaecologyTags :

New Findings on Cardiovascular Risk, Menopause and Migraines Ease Concerns

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Research suggesting a link between migraines and menopause symptoms and cardiovascular disease has gotten a lot of attention. But a pair of new studies in the journal Menopause suggest that most women experiencing these symptoms can rest easier, especially if they don’t have both migraines and long-term hot flashes and night sweats.

Instead, they should focus on tackling the other factors that can raise their cardiovascular risk by getting more sleep, exercise and healthy foods, quitting tobacco, and minding their blood pressure, blood sugar, cholesterol and weight.

For women who have experienced both migraines and hot flashes or night sweats over many years, one of the new studies does suggest an extra level of cardiovascular risk.

That makes heart disease and stroke prevention even more important in this group, says study leader Catherine Kim, MD, MPH, of the University of Michigan.

And for women currently in their 20s and 30s who experience migraines, the new research suggests that they might be heading for a higher risk of long-term menopause-related symptoms when they get older.

Long-term study yields important insights

Kim and her colleagues at Michigan Medicine, U-M’s academic medical centre, published the new pair of studies based on an in-depth analysis of data from a long-term study of more than 1900 women who volunteered to have regular physical exams and blood tests, and to take yearly health surveys, when they were in their late teens to early 30s.

Those women, now in their 50s and 60s, have provided researchers with a priceless view of what factors shape health in the years leading up to menopause and beyond, through their continued participation in the CARDIA study.

“The anxiety and dread that women with migraines and menopausal symptoms feel about cardiovascular risk is real – but these findings suggest that focusing on prevention, and correcting unhealthy habits and risk factors, could help most women,” said Kim, who is an associate professor of internal medicine at U-M and a primary care physician.

“For the subgroup with both migraines and early persistent hot flashes and night sweats, and for those currently experiencing migraines in their early adulthood, these findings point to an added need to control risks, and address symptoms early,” she adds.

Just over 30% of the middle-aged women in the study reported they had persistent hot flashes and night sweats, which together are called vasomotor symptoms or VMS because they relate to changes in the diameter of blood vessels.

Of them, 23% had reported also having migraines. This was the only group for whom Kim and her colleagues found extra risk of stroke, heart attack or other cardiovascular events that couldn’t be explained by other risk factors that have long been known to be linked to cardiovascular problems.

In addition to those with persistent vasomotor symptoms starting in their 40s or before, 43% of the women in the study had minimal levels of such symptoms in their 50s, and 27% experienced an increase in VMS over time into their 50s and early 60s.

The latter two groups had no excess cardiovascular risk once their other risk factors were taken into account, whether or not they had migraines.

Use of hormone-based birth control and estrogen to address medical issues did not affect this risk.

Controlling destiny

In the study of data from the same women in their earlier stages of life, the researchers found that the biggest factors in predicting which ones would go on to have persistent hot flashes and night sweats were having migraines, having depression, and smoking cigarettes, as well as being Black or having less than a high school education.

“These two studies, taken together, underscore that not all women have the same experiences as they grow older, and that many can control the risk factors that might raise their chances of heart disease and stroke later in life,” said Kim.

“In other words, women can do a lot to control their destiny when it comes to both menopause symptoms and cardiovascular diseases.”

She notes that the American Heart Association calls these risk factors the “Essential 8” and offers guides for what women, men and even children and teens can do to address them.

Evolving knowledge and treatment

The long-term study that the two new findings come from was specifically designed to look at cardiovascular risks when it launched in the mid-1980s. CARDIA stands for Coronary Artery Risk Development in Young Adults.

Back in the 80s, knowledge about the biology of blood vessels, down to the cellular and molecular level, was nowhere near where it is today. Both vasomotor symptoms in menopause and migraines have to do with blood vessel contraction and dilation.

But decades of research has shown the microscopic impacts on blood vessels of years of smoking, poor sleep, poor eating habits and lack of activity, as well as a person’s genetic inheritance, life experiences and hormonal history.

Newer injectable migraine medications called calcitonin gene-related peptide (CGRP) antagonists have reached the market in recent years. Using monoclonal antibodies, they target a key receptor on the surface of blood vessel cells to prevent migraines and cluster headaches. But they are expensive and not covered by insurance for all people with migraines.

While the new study is based on data from years before these medications became available, Kim said she recommends them to her patients with persistent migraines, as well as working with them to understand what triggers their migraines and how to use other medications including pain relievers and antiseizure medications to prevent them.

She also notes that the paper on future risk of persistent hot flashes and night sweats echoes the recent trend of using antidepressant medications to try to ease these menopause effects.

Kim also says that evidence has grown about the importance of healthy sleep habits for reducing hot flashes, as well the short-term use of oestradiol-based hormone therapy patches, which have not been shown to have a link to cardiovascular risk. And, she notes that research has not shown any over-the-counter supplement or herbal remedy to be effective, and that these are far less regulated than medications.

Source: Michigan Medicine – University of Michigan

Categories : Neurology Obstetrics & GynaecologyTags :

Polycystic Ovary Syndrome Tied to Cognitive Problems

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Those with polycystic ovary syndrome (PCOS) may be more likely to have memory and thinking problems in middle age, according to a study involving over 900 women, 66 of whom had PCOS. The study, published in Neurology, followed the women for 30 years.

PCOS is a hormonal disorder that is defined by irregular menstruation and elevated levels of androgen. Other symptoms may include excess hair growth, acne, infertility and poor metabolic health.

“Polycystic ovary syndrome is a common reproductive disorder that impacts up to 10% of women,” said study author Heather G. Huddleston, MD, of the University of California, San Francisco.

“While it has been linked to metabolic diseases like obesity and diabetes that can lead to heart problems, less is known about how this condition affects brain health. Our results suggest that people with this condition have lower memory and thinking skills and subtle brain changes at midlife. This could impact a person on many levels, including quality of life, career success and financial security.”

The study involved 907 female participants who were 18 to 30 years old at the start of the study.

They were followed for 30 years, at which time they completed tests to measure memory, verbal abilities, processing speed and attention. At the time of testing, 66 participants had polycystic ovary syndrome.

In a test measuring attention, participants looked at a list of words in different colours and were asked to state the colour of the ink rather than read the actual word. For example, the word “blue” could be displayed in red, so the correct response would be red.

Researchers found for this test, people with PCOS had an average score that was approximately 11% lower compared to people without the condition.

After adjusting for age, race and education, researchers found that people with polycystic ovary syndrome had lower scores on three of the five tests that were given, specifically in areas of memory, attention and verbal abilities, when compared to those without this condition.

At years 25 and 30 of the study, a smaller group of 291 participants had brain scans.

Of those, 25 had PCOS. With the scans, researchers looked at the integrity of the white matter pathways in the brain by looking at movement of water molecules in the brain tissue.

Researchers found that people with PCOS had lower white matter integrity, which may indicate early evidence of brain aging.

“Additional research is needed to confirm these findings and to determine how this change occurs, including looking at changes that people can make to reduce their chances of thinking and memory problems,” Huddleston said.

“Making changes like incorporating more cardiovascular exercise and improving mental health may serve to also improve brain aging for this population.”

A limitation of the study was that PCOS diagnosis was not made by a doctor but was based on androgen levels and self-reported symptoms, so participants may not have remembered all the information accurately.

The study was funded by the University of California, San Francisco.

Source: American Academy of Neurology 

Categories : Obstetrics & GynaecologyTags :

New Study Sheds Light on Placenta Accreta Spectrum Disorder

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A new UCLA-led study published in American Journal of Obstetrics & Gynecology may change the way clinicians and scientists understand, diagnose and treat placenta accreta spectrum disorder, a serious condition in which the placenta fails to separate from the uterus at birth. Researchers previously believed that certain overly invasive placental cells, called trophoblasts, were responsible for keeping the connection intact.

But this new research, which identifies genetic and cellular changes within single cells where the placenta and uterus join, shifts the focus to how the structural support of tissues, and the blood vessels of the uterus, can cause a “loss of normal boundary limits” between the placenta and the uterus.

“We utilized two new techniques in single-cell analysis to create an atlas of cells involved in placenta accreta to better understand this increasingly prevalent disorder that can have devastating implications for maternal and neonatal health,” said Dr Yalda Afshar, a maternal-foetal medicine specialist and researcher at the David Geffen School of Medicine at UCLA, and the first and corresponding author.

“This work revealed a subset of genes differentially expressed in placenta accreta spectrum disorder, which provides the basis for the ‘permissive environment’ for the placenta to attach to the uterine lining,” said Dr Deborah Krakow, a maternal-foetal medicine specialist and researcher, chair of the Department of Obstetrics and Gynecology at the David Geffen School of Medicine at UCLA, and the paper’s senior author.

The research showed that the decidua, the layer of the uterine lining that forms during pregnancy, and blood vessels, are sending different signals to the placenta when a pregnant person has placenta accreta.

In placenta accreta, the placenta is stuck on too tight, which becomes the reason for many of the maternal complications of placenta accreta.

“Our goal was to characterize the intimate relationship between the maternal and fetal tissue at the site of accreta or malfunction,” Afshar said.

“The genes and signaling pathways we identified go beyond providing a better understanding of the mechanism of the disease; they may be used as targets to help us refine diagnostic tests, track disease progression over time, and discover new, more effective therapies.”

The incidence of placenta accreta spectrum (PAS) disorders has increased dramatically in recent decades, the cause of which is not certain, though cesarean deliveries, is one of several risk factors.

Today, incidence is estimated at 1 in 272 births in the U.S., up from 1 in about 30 000 pregnancies in the 1960s, researchers say.

For this study, the research team performed multiple placental biopsies on 12 placentas, six with PAS disorder and six controls, conducting single-cell RNA analysis on 31 406 individual cells.

The researchers also applied spatial transcriptomics to 36 regions of interest: 12 in PAS-adherent, 12 in PAS-nonadherent, and 12 in controls.

Spatial transcriptomics allow researchers to precisely measure and map the gene activity within a single tissue sample.

“At the end of the day, understanding the biology of pregnancy and pregnancy-related diseases, like accreta, is inspired by only one thing – finding ways to improve the care we can provide to pregnant people and their families,” said Afshar, a physician-scientist who manages the care of many patients with placenta accreta spectrum disorders at UCLA Health.

Source: University of California – Los Angeles Health Sciences

Categories : Exercise Obstetrics & GynaecologyTags :

Vegan Diet in Pregnancy may Increase Preeclampsia and Low Birth Weight Risks

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Women who follow vegan diets during pregnancy may face higher risks of developing preeclampsia and of giving birth to newborns with lower birth weight, suggests a recent study published in Acta Obstetricia et Gynecologica Scandinavica.

For the study, 65 872 women identified themselves as omnivorous, 666 as fish/poultry vegetarians, 183 as lacto/ovo vegetarians, and 18 as vegans. Based on a questionnaire completed mid-pregnancy, investigators found that protein intake was lower among lacto/ovo vegetarians (13.3%) and vegans (10.4%) compared with omnivorous participants (15.4%). Micronutrient intake was also much lower among vegans, but when dietary supplements were considered, no major differences were observed.

Compared with omnivorous mothers, vegan mothers had a higher prevalence of preeclampsia (a pregnancy complication characterised by high blood pressure), and their newborns weighed an average of 240 g less.

“Further research is needed regarding possible causality between plant-based diets and pregnancy and birth outcomes, to strengthen the basis for dietary recommendations,” the authors wrote.

Source: Wiley

Categories : Exercise Obstetrics & GynaecologyTags :

Swimming in Cold Water Improves Menopause Symptoms

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Researchers have found that swimming in cold water results in a significant improvement in menopause symptoms for women. The research, published in Post Reproductive Health, surveyed 1114 women, 785 of which were going through the menopause, to examine the effects of cold water swimming on their health and wellbeing.

The findings showed that menopausal women experienced a significant improvement in anxiety (as reported by 46.9% of the women), mood swings (34.5%), low mood (31.1%) and hot flushes (30.3%) as a result of cold water swimming.

In addition, a majority of women (63.3%) swam specifically to relieve their symptoms.

Some of the women quoted in the study said that they found the cold water to be “an immediate stress/ anxiety reliever” and described the activity as “healing.”

One 57-year-old woman stated: “Cold water is phenomenal. It has saved my life. In the water, I can do anything. All symptoms (physical and mental) disappear and I feel like me at my best.”

Senior author, Professor Joyce Harper (UCL EGA Institute for Women’s Health), said: “Cold water has previously been found to improve mood and reduce stress in outdoor swimmers, and ice baths have long been used to aid athletes’ muscle repair and recovery.

“Our study supports these claims, meanwhile the anecdotal evidence also highlights how the activity can be used by women to alleviate physical symptoms, such as hot flushes, aches and pains.

“More research still needs to be done into the frequency, duration, temperature and exposure needed to elicit a reduction in symptoms. However, we hope our findings may provide an alternative solution for women struggling with the menopause and encourage more women to take part in sports.”

Most of the women involved in the study were likely to swim in both summer and winter and wear swimming costumes, rather than wet suits.

Alongside aiding menopausal symptoms, the women said their main motivations for cold water swimming were being outside, improving mental health and exercising.

Professor Harper said: “The majority of women swim to relieve symptoms such as anxiety, mood swings and hot flushes. They felt that their symptoms were helped by the physical and mental effects of the cold water, which was more pronounced when it was colder.

“How often they swam, how long for and what they wore were also important. Those that swam for longer had more pronounced effects. The great thing about cold water swimming is it gets people exercising in nature, and often with friends, which can build a great community.”

The researchers also wanted to investigate whether cold water swimming improved women’s menstrual symptoms.

Of the 711 women who experienced menstrual symptoms, nearly half said that cold water swimming improved their anxiety (46.7%), and over a third said that it helped their mood swings (37.7%) and irritability (37.6%).

Yet despite the benefits of cold water swimming, the researchers were also keen to highlight that the sport comes with certain risks.

Professor Harper explained: “Caution must be taken when cold water swimming, as participants could put themselves at risk of hypothermia, cold water shock, cardiac rhythm disturbances or even drowning.

“Depending on where they are swimming, water quality standards may also vary. Raw sewage pollution is an increasingly common concern in UK rivers and seas. And, sadly, this can increase the likelihood of gastroenteritis and other infections.”

Study limitations

The study may contain some bias due to the survey only being taken by women who already cold water swim. And, as the survey was conducted online, it is likely that women were more likely to complete the survey if they noticed an association between menopause symptoms and cold water swimming.

Source: University College London

Categories : Lab Tests and Imaging Obstetrics & GynaecologyTags :

New Ultrasound Method can Predict Risk of Preterm Delivery

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Researchers have developed a way to use ultrasound to estimate the risk of delivering a baby preterm. The new method measures microstructural changes in a woman’s cervix using quantitative ultrasound. The method works as early as 23 weeks into a pregnancy, according to the research, which is published in the American Journal of Obstetrics & Gynecology Maternal Fetal Medicine.

The current method for assessing a woman’s risk of preterm birth is based solely on whether she has previously given birth prematurely. This means there has been no way to assess risk in a first-time pregnancy.

“Today, clinicians wait for signs and symptoms of a preterm birth,” such as a ruptured membrane, explained lead author Barbara McFarlin, a professor emeritus of nursing at University of Illinois Chicago.

“Our technique would be helpful in making decisions based on the tissue and not just on symptoms.”

The new method is the result of more than 20 years of collaboration between researchers in nursing and engineering at UIC and University of Illinois Urbana-Champaign. In a study of 429 women who gave birth without induction at the University of Illinois Hospital, the new method was effective at predicting the risk of preterm births during first-time pregnancies.

And for women who were having a subsequent pregnancy, combing the data from quantitative ultrasound with the woman’s delivery history was more effective at assessing risk than just using her history.

The new approach differs from a traditional ultrasound where a picture is produced from the data received.

In quantitative ultrasound, a traditional ultrasound is performed but the radio frequency data itself is read and analysed to determine tissue characteristics.

The study is the culmination of a research partnership that began in 2001 when McFarlin was a nursing PhD student at UIC. Having previously worked as a nurse midwife and sonographer, she had noticed that there were differences in the appearance of the cervix in women who went on to deliver preterm.

She was interested in quantifying this and discovered that “no one was looking at it.”

She was put in touch with Bill O’Brien, a UIUC professor of electrical and computer engineering, who was studying ways to use quantitative ultrasound data in health research.

Together, over the past 22 years, they established that quantitative ultrasound could detect changes in the cervix and, as McFarlin had suspected long ago, that those changes help predict the risk of preterm delivery.

The preterm birth rate hovers around 10-15% of pregnancies, O’Brien said.

“That’s a very, very high percentage to not know what is happening,” he said.

If a clinician could know at 23 weeks that there was a risk of preterm birth, they would likely conduct extra appointments to keep an eye on the foetus, the researchers said.

But since there had previously been no routine way to assess preterm birth risk this early, there have been no studies to show what sort of interventions would be helpful in delaying labour.

This study, O’Brien explains, will allow other researchers to “start studying processes by which you might be able to prevent or delay preterm birth.”

Source: University of Illinois Chicago

Categories : Diseases, Syndromes and Conditions Obstetrics & GynaecologyTags :

Clear Link between Autoimmune Disease and Perinatal Depression

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This is a pseudo-colored image of high-resolution gradient-echo MRI scan of a fixed cerebral hemisphere from a person with multiple sclerosis. Credit: Govind Bhagavatheeshwaran, Daniel Reich, National Institute of Neurological Disorders and Stroke, National Institutes of Health

Women with autoimmune disease are more likely to suffer from depression during pregnancy and after childbirth; conversely, women with a history of perinatal depression are at higher risk of developing autoimmune disease, according to a new study from Karolinska Institutet which is published in the journal Molecular Psychiatry.

Some of the most common autoimmune diseases are gluten intolerance (coeliac disease), autoimmune thyroiditis, rheumatoid arthritis, type 1 diabetes, and multiple sclerosis (MS). 

In the present study, researchers used data from the Swedish Medical Birth Register and identified all women who had given birth in Sweden between 2001 and 2013. Out of the resulting group of approximately 815 000 women and 1.3 million pregnancies, just over 55 000 women had been diagnosed with depression during their pregnancy or within a year after delivery. 

The researchers then compared the incidence of 41 autoimmune diseases in women with and without perinatal depression, controlling for familial factors such as genes and childhood environment by also including the affected women’s sisters.

Strongest association for MS

The results reveal a bidirectional association between perinatal depression and autoimmune thyroiditis, psoriasis, MS, ulcerative colitis, and coeliac disease. Overall, women with autoimmune disease were 30 per cent more likely to suffer perinatal depression. Conversely, women with perinatal depression were 30 per cent more likely to develop a subsequent autoimmune disease.

The association was strongest for the neurological disease MS, for which the risk was double in both directions. It was also strongest in women who had not had a previous psychiatric diagnosis.

“Our study suggests that there’s an immunological mechanism behind perinatal depression and that autoimmune diseases should be seen as a risk factor for this kind of depression,” says the study’s first author Emma Bränn, researcher at the Institute of Environmental Medicine at Karolinska Institutet.

Can have serious consequences

The researchers will now continue to examine the long-term effects of depression during pregnancy and in the first year following childbirth.

“Depression during this sensitive period can have serious consequences for both the mother and the baby,” says Dr Bränn. “We hope that our results will help decision-makers to steer funding towards maternal healthcare so that more women can get help and support in time.”

Since this was an observational study, no conclusions on causality can be drawn.

The study was financed by Karolinska Institutet, Forte (the Swedish Research Council for Health, Working Life and Welfare), the Swedish Research Councill and the Icelandic Research Fund. The researchers report no conflicts of interest.

Source: Karolinska Institutet

Categories : Mental Health Obstetrics & GynaecologyTags :

Perinatal Depression Triples the Risk of Suicidal Behaviour

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Maternal suicide is an alarming public health issue and the second most common cause of death during the postnatal period. New research from Karolinka Institutet in Sweden shows that mothers with clinically diagnosed perinatal depression had a three times higher risk of suicidal behaviour compared to mothers without perinatal depression. The findings were published in JAMA Network Open.

Some 13–36% of maternal deaths are attributable to suicide, and the consequences are devastating to the newborn and the family. Maternal suicide is linked to a complex interplay of risk factors, including history of psychiatric disorders, socioeconomic disparities, and inadequate access to healthcare service. It is of paramount importance to identify high-risk populations for preventing maternal suicide and suicidal attempt.

Our findings suggest that women with clinically diagnosed PND are at an increased risk of suicidal behavior, particularly within one year after PND yet throughout 18 years of follow-up. This highlights the pressing need for vigilant clinically monitoring and prompt intervention for this vulnerable population to prevent such devastating outcomes, regardless of pre-pregnancy history of psychiatric disorders.

Hang Yu, PhD student

In this nationwide population-matched cohort study with a maximal follow-up of 18 years, 86 551 women with PND from 2001 to 2017 and 865 510 unaffected women individually matched on age and calendar year at delivery. Sibling comparison was employed to account for familial confounding. It was found that women with a clinical diagnosis of PND have an elevated risk of suicidal behaviour compared to population-matched women or their full sisters without PND. Attenuated yet still substantially elevated risks were observed when comparing with full sisters without PND who share partial genetic and familial environmental factors with affected women. Importantly, such excess risk was apparent among women regardless of their history of psychiatric disorders, suggesting that PND is linked to an added risk of suicidal behaviour beyond that the risk associated with psychiatric disorders occurring before the perinatal period. Moreover, the risk elevations were particularly high shortly after the PND diagnosis, and despite of the rapid decline over time, remained throughout 18 years of follow-up.

Source: Karolinska Institutet

Categories : General Interest Obstetrics & GynaecologyTags :

Gauteng Health Rings in the New Year with 112 Births

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New Year’s Day saw the Gauteng Department of Health welcoming 112 babies into the world, the lion’s share of more than 400 births in total for the country. According to data released by Gauteng Health on X/Twitter, in the province’s public healthcare facilities, there were a total of 59 boys and 53 girls. Thelle Mogoerane Regional Hospital topped the table with 10 babies, followed by Chris Hani Baragwanath Academic Hospital (CHBAH) with 9 babies. But all of this was relatively quiet compared to Christmas Day, which saw more than three times the New Years’ Day number.

MEC Nkomo Nomantu together with MMC for Health Rina Marx joined the postpartum mothers at Dr George Mukhari Academic Hospital on the morning of New Year’s Day in welcoming their new arrivals. Gauteng’s academic hospitals recorded 19 births, while there were 10 births at the tertiary hospitals. Regional and district hospitals had 69 births and community healthcare centres had 14.

Christmas Day saw 387 babies born, 201 of them girls and 186 boys. CHBAH welcomed the most, with 46 births, followed by Tembisa Hospital with 38.

Categories : Obstetrics & GynaecologyTags :

Cause of Pregnancy Sickness – and Potential Treatment

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A Cambridge-led study has shown why many women experience nausea and vomiting during pregnancy – and why some women, including the Duchess of Cambridge, become so sick they need to be admitted to hospital.

The culprit is a hormone produced by the foetus – a protein known as GDF15. But how sick the mother feels depends on a combination of how much of the hormone is produced by the foetus

The discovery, published today in Nature, points to a potential way to prevent pregnancy sickness by exposing mothers to GDF15 ahead of pregnancy to build up their resilience.

As many as seven in ten pregnancies are affected by nausea and vomiting. In some women – thought to be between one and three in 100 pregnancies – it can be severe, even threatening the life of the foetus and the mother and requiring intravenous fluid replacement to prevent dangerous levels of dehydration. So-called hyperemesis gravidarum is the commonest cause of admission to hospital of women in the first three months of pregnancy.

Although some therapies exist to treat pregnancy sickness and are at least partially effective, widespread ignorance of the disorder compounded by fear of using medication in pregnancy mean that many women with this condition are inadequately treated.

Until recently, the cause of pregnancy sickness was entirely unknown. Recently, some evidence, from biochemical and genetic studies has suggested that it might relate to the production by the placenta of the hormone GDF15, which acts on the mother’s brain to cause her to feel nauseous and vomit.

Now, an international study, involving scientists at the University of Cambridge and researchers in Scotland, the USA and Sri Lanka, has made a major advance in understanding the role of GDF15 in pregnancy sickness, including hyperemesis gravidarum.

The team studied data from women recruited to a number of studies, including at the Rosie Maternity Hospital, part of Cambridge University Hospitals NHS Foundation Trust and Peterborough City Hospital, North West Anglia NHS Foundation Trust. They used a combination of approaches including human genetics, new ways of measuring hormones in pregnant women’s blood, and studies in cells and mice.

The researchers showed that the degree of nausea and vomiting that a woman experiences in pregnancy is directly related to both the amount of GDF15 made by the foetal part of placenta and sent into her bloodstream, and how sensitive she is to the nauseating effect of this hormone.

GDF15 is made at low levels in all tissues outside of pregnancy. How sensitive the mother is to the hormone during pregnancy is influenced by how much of it she was exposed to prior to pregnancy – women with normally low levels of GDF15 in blood have a higher risk of developing severe nausea and vomiting in pregnancy..

The team found that a rare genetic variant that puts women at a much greater risk of hyperemesis gravidarum was associated with lower levels of the hormone in the blood and tissues outside of pregnancy. Similarly, women with the inherited blood disorder beta thalassemia, which causes them to have naturally very high levels of GDF15 prior to pregnancy, experience little or no nausea or vomiting.

Professor Sir Stephen O’Rahilly, Co-Director of the Wellcome-Medical Research Council Institute of Metabolic Science at the University of Cambridge, who led the collaboration, said: “Most women who become pregnant will experience nausea and sickness at some point, and while this is not pleasant, for some women it can be much worse – they’ll become so sick they require treatment and even hospitalisation.

“We now know why: the baby growing in the womb is producing a hormone at levels the mother is not used to. The more sensitive she is to this hormone, the sicker she will become. Knowing this gives us a clue as to how we might prevent this from happening. It also makes us more confident that preventing GDF15 from accessing its highly specific receptor in the mother’s brain will ultimately form the basis for an effective and safe way of treating this disorder.”

Mice exposed to acute, high levels of GDF15 showed signs of loss of appetite, suggesting that they were experiencing nausea, but mice treated with a long-acting form of GDF15 did not show similar behaviour when exposed to acute levels of the hormone. The researchers believe that building up woman’s tolerance to the hormone prior to pregnancy could hold the key to preventing sickness.

Co-author Dr Marlena Fejzo from the Department of Population and Public Health Sciences at the University of Southern California whose team had previously identified the genetic association between GDF15 and hyperemesis gravidarum, has first-hand experience with the condition. “When I was pregnant, I became so ill that I could barely move without being sick. When I tried to find out why, I realised how little was known about my condition, despite pregnancy nausea being very common.

“Hopefully, now that we understand the cause of hyperemesis gravidarum, we’re a step closer to developing effective treatments to stop other mothers going through what I and many other women have experienced.”

The work involved collaboration between scientists at the University of Cambridge, University of Southern California, University of Edinburgh, University of Glasgow and Kelaniya University, Colombo, Sri Lanka. The principal UK funders of the study were the Medical Research Council and Wellcome, with support from the National Institute for Health and Care Research Cambridge Biomedical Research Centre.

The original text of this story is licensed under a Creative Commons License. 

Source: University of Cambridge