Category: Obstetrics & Gynaecology

Categories : Addiction Obstetrics & GynaecologyTags :

Falling Pregnant Unconsciously Curbs Smoking

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pregnant woman holding her belly
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Pregnant smokers reduced their smoking by an average of one cigarette per day before becoming aware they were pregnant, according to a new study in in Addiction Biology. In the month after learning of their pregnancy, participants reduced smoking by another four cigarettes per day.

“Our findings suggest that pregnancy could curb smokers’ desire to smoke before they are even aware of having conceived,” said the study’s lead author and principal investigator, Dr Suena Huang Massey, associate professor of psychiatry and behavioural sciences and medical social sciences at Northwestern University Feinberg School of Medicine.

“While recognition of pregnancy is a common motivation to reduce or quit smoking, if biological processes in early pregnancy are also involved as suggested by this study, identifying precisely what these processes are can lead to the development of new smoking-cessation medications.”

The vast majority of research in this field focuses on the impact of a person’s smoking on the pregnancy and the baby. This study examines, instead, the impact of pregnancy on a person’s smoking behaviour.

Though it is well known that smoking is reduced in pregnancy, it was not known when it started and whether the smokers knew they were pregnant.

“Before this paper, it was largely assumed that the only thing causing pregnant smokers to cut down was a desire to protect the baby,” Dr Massey said. “While our study does support the discovery of pregnancy as a salient event, levels of pregnancy smoking began to decline before smokers suspected they were pregnant.”

These findings support a new line of research into what happens biologically during pregnancy that might be interrupting addictive behaviours, Massey said. Her hope is that the answer to this question will lead to the discovery of new and improved ways to treat addiction.

Pregnancy hormones a contributing factor?

Human chorionic gonadotropin (hCG) is a hormone produced by the placenta in early pregnancy that is linked to morning sickness (nausea and vomiting during pregnancy).

“Strikingly, we observed the steepest declines in smoking precisely when hCG levels typically peak – between five and 10 weeks of pregnancy,” Massey said. “What’s more, pregnant smokers who do not quit during the first trimester (when hCG levels are elevated) are unlikely to quit before delivery, even with assistance from medications or financial incentives.”

Study methodology

Scientists estimated changes in cigarettes per day smoked, reported retrospectively, by 416 participants from two independent cohorts (145 from 2000 to 2005 and 271 from 2006 to 2009). Every participant was a smoker prior to becoming pregnant. Women in the study were interviewed about their smoking habits at 16 weeks of pregnancy and provided urine samples, so researchers could verify their reports.

On average, participants smoked about 10 cigarettes per day before conception. Between conception and the date they realised they were pregnant (highly variable and reported by each participant), smoking fell by an average of one cigarette per day. In the month after recognising the pregnancy, smoking dropped from an average of 9 cigarettes per day to five. Importantly, these declines were seen whether pregnancies were planned or unplanned, and whether smokers quit or did not quit.

Source: Northwestern University

Categories : Obstetrics & GynaecologyTags :

Diet Could Contribute to Menstrual Pain in Adolescent Girls

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Despite the fact that dysmenorrhoea is the leading cause of school absences for adolescent girls, few girls seek treatment. A review suggests that diet may be a key contributor, specifically diets high in meat, oil, sugar, salt, and coffee, which have been shown to cause inflammation. Results will be presented during The North American Menopause Society (NAMS) Annual Meeting in Atlanta, October 12-15, 2022.

Roughly 90% of adolescent girls experience menstrual pain. Most use over-the-counter medicine to manage the pain, with limited improvement. Evidence has highlighted that diets high in omega-3 fatty acids and low in processed foods, oil, and sugar reduce inflammation, a key contributor to menstrual pain.

This analysis was designed to study the effect of diet on menstrual pain and identify which foods contribute to it and which can reduce it. Research was conducted through a literature review that found multiple studies that examined dietary patterns that resulted in menstrual pain. In general terms, these studies found that diets high in omega-6 fatty acids promote inflammation and foods high in omega-3 fatty acids reduce it. The muscles in the uterus contract because of prostaglandins, which are active in inflammatory responses. When measuring the Dietary Inflammatory Index, it was found that those on a vegan diet (that excluded animal fat) had the lowest rates of inflammation.

“Researching the effects of diet on menstrual pain started as a search to remedy the pain I personally experienced; I wanted to understand the science behind the association. Learning about different foods that increase and decrease inflammation, which subsequently increase or reduce menstrual pain, revealed that diet is one of the many contributors to health outcomes that is often overlooked. I am hopeful that this research can help those who menstruate reduce the pain they experience and shed light on the importance of holistic treatment options,” said Serah Sannoh, lead author of the poster presentation from Rutgers University.

“Since menstrual pain is a leading cause of school absenteeism for adolescent girls, it’s important to explore options that can minimise the pain. Something like diet modification could be a relatively simple solution that could provide substantial relief for them,” said Dr Stephanie Faubion, NAMS medical director.

Source: EurekAlert!

Categories : Mental Health Obstetrics & GynaecologyTags :

Biological Changes in Mothers Experiencing Postpartum Depression

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Newly discovered biological changes in mothers who suffer postpartum depression may help explain the condition, yield long-sought treatments and let doctors identify those at risk even before their babies are born. The findings were published in Molecular Psychiatry.

Postpartum depression strikes up to 20% of new mothers, and roughly 20% of maternal deaths after childbirth are from suicide. Postpartum depression can cause anxiety and irritability, feelings of self-doubt and difficulty bonding with the baby, cognitive impairment, and interfering with sleeping and eating. For the child, maternal postpartum depression can lead to cognitive, emotional and social development problems.

Risk factors for postpartum depression are thought to include the mother’s age at childbirth, diabetes and prior history of mental health issues. But the new discovery suggests a previously unknown biological contributor: an impairment of the body’s ability to clean up old genetic material and other cellular debris.

“The finding that cells aren’t cleaning out old proteins and cellular debris, called autophagy, occurs before women develop depression symptoms, indicating that it could be part of the disease process,” explained Jennifer L. Payne, MD, director of the Reproductive Psychiatry Research Program at the University of Virginia School of Medicine. “There are several medications that promote autophagy in cells, so this finding might open the door to new treatments and to identification of women at risk of postpartum depression before they become ill.”

Understanding Postpartum Depression

Dr Payne and colleagues wanted to determine if ‘extracellular RNA communication’, a newly discovered form of communication among cells, might contribute to postpartum depression. Extracellular RNA communication is heightened during pregnancy and is critical in embryo implantation and in the body’s inflammatory response afterward.

The researchers analysed blood plasma samples from 14 research participants with and without postpartum depression, collected during and after their pregnancies. The researchers found that extracellular RNA communication in immune cells was altered extensively in women who suffered postpartum depression. Further, they determined that this “large and consistent” change significantly limited the women’s bodies’ ability to perform important cellular cleanup – suggesting a potential biological cause for their depression.

“Deficits in autophagy are thought to cause toxicity that may lead to the changes in the brain and body associated with depression,” Dr Payne said. “We have never fully understood the biological basis for postpartum depression, and this finding gets us closer to an understanding.”

Source: University of Virginia Health System

Categories : Cardiovascular Disease Obstetrics & GynaecologyTags :

Study Demonstrates Safer Preeclampsia Treatment with Nifedipine

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Image by Hush Naidoo from Unsplash
Image by Hush Naidoo from Unsplash

Women with severe preeclampsia may be treated with extended-release nifedipine, a blood pressure-lowering medicine, daily during the labour and delivery process, according to new research published today in Hypertension. Women receiving the drug had a lower risk of dangerously high blood pressure that would require treatment with fast-acting medicines including intravenous (IV) medications.

The study examined whether treatment with nifedipine, an extended-release blood pressure-lowering medication, leading up to labour and delivery may prevent severe blood pressure levels from developing, and, as a result, avoid the need to administer fast-acting IV medications.

According to the American Heart Association, preeclampsia is typically diagnosed after 20 weeks of pregnancy and indicates high blood pressure measures with symptoms such as headaches, vision changes and swelling of the hands, feet, face or eyes. It affects up to 8% of pregnancies. A diagnosis of preeclampsia with severe features typically includes systolic BP of ≥ 160mmHg and/or diastolic BP ≥ 110mmHg, and proteinuria. It increases the risk of stroke, liver or kidney damage and pre-term delivery. Delivery of the baby is the only way to start to cure preeclampsia, and symptoms usually go away within days of delivery. However, some women require BP medication for six weeks after delivery or longer.

“We know that bringing down very high blood pressure to a safer range will help prevent maternal and foetal complications. However, besides rapid-acting, IV medicines for severe hypertension during pregnancy, optimal management for hypertension during the labour and delivery process, has not been studied,” said lead study author Erin M. Cleary, MD.

Sever hypertension also raises the risk for complications such as placental abruption, leading to serious complications for mother and/or the baby.

“Some of these complications may include emergency delivery, blood loss for the mother and may be life threatening for both the mother and baby,” Dr Cleary said. “About 10% of patients treated with a rapid-IV treatment for very high blood pressure may quickly have very low blood pressures. When blood pressure gets too low, too fast, that can lead to other serious complications.”

The study was conducted from June 2020 to April 2022 at The Ohio State University Wexner Medical Center and included 110 women who were at least 22 weeks pregnant, diagnosed with severe preeclampsia and who underwent induction of labour. Half were randomised to take a 30mg oral pill nifedipine extended-release once a day until delivery, the other half took a placebo pill daily until delivery. Participants were followed through hospital discharge, and chart review was performed through six weeks postpartum to monitor for any postpartum readmissions along with reasons for readmission.

The researchers also examined the impact of nifedipine treatment on delivery, if and how long the baby may have needed care in the neonatal intensive care unit (NICU) and other adverse outcomes for the mother and/or baby.

The study found:

  • 34% of women in the nifedipine group needed acute hypertension therapy compared to 55.1% of those in the placebo group.
  • There were fewer Caesarean deliveries among the women treated with nifedipine: 20.8% of women in the nifedipine treatment group had a Caesarean section, compared to 34.7% of women in the placebo group.
  • The rate of NICU admission for the newborns was lower if the mother was treated with nifedipine (29.1%) compared to the placebo group (47.1%).
  • Poor outcomes for the infant – such as lower Apgar score, low blood sugar levels, high bilirubin or needing extra oxygen – did not differ significantly between the two treatment groups.

It’s important to note, however, that the number of participants in this study was too small to determine whether the differences in the NICU and Caesarean rates may hold true or if they may be due to chance or other factors. The researchers plan to conduct larger studies with more participants to better understand if these differences are valid.

Source: American Heart Association

Categories : Obstetrics & GynaecologyTags :

An Easy-to-use Model for Assessing Hysterectomy Complication Risk

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Researchers have developed easy-to-use online prediction tools that provide personalised risk estimates for patients undergoing hysterectomy for benign disease. The models are described in a study published in the Canadian Medical Association Journal.

Hysterectomy is one of the most common surgical procedures, with one-third of women in Canada undergoing this procedure before age 60. Laparoscopic hysterectomies are more common as they are less invasive than abdominal surgery. Current practice entails that surgeons discuss benefits of the type of procedure and risks of complications with patients.

The researchers developed and tested prediction models with the aim of supplementing a surgeon’s expert opinion on patients’ risks of complications from hysterectomy. Hysterectomy complications can include ureteric, gastrointestinal and vascular injury as well as wound complications. The authors used data from the English National Health Service (NHS) on 68 599 women who had laparoscopic hysterectomies and 125 971 women who had abdominal hysterectomies between 2011 and 2018.

“Historically, a surgeon’s gut feeling has been shown to be a good indicator of postoperative outcomes; however, an expert opinion is the lowest value in evidence-based medicine,” said Dr Krupa Madhvani, Queen Mary University of London. “Although a surgeon’s experience and expert opinion carries utility, it cannot be used solely to guide risk management. In Canada and globally, the overall rate of hysterectomy for benign disease is declining, and more patients are undergoing surgery by lower-volume surgeons, who may not have expertise in every procedure,” write the authors.

Using 11 predictors, such as age, body mass index and diabetes, the researchers also included ethnicity as a potential risk factor.

“Ethnicity has been shown to be an independent factor influencing the route and complications of hysterectomy,” the authors wrote.

They found women of Asian background were at higher risk of major complications after abdominal hysterectomy compared with women who were white, although the risk was not associated with laparoscopy. The most significant risk factor for major complications in both procedures were the presence of adhesions, which is consistent with existing evidence.

“These tools will guide shared decision-making and may lead to referral to centres with greater surgical expertise or to exploration of nonsurgical treatment options,” the authors wrote.

Source: EurekAlert!

Categories : Obstetrics & GynaecologyTags :

‘Wear and Tear’ of Stress Impacts Ability to Fall Pregnant

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pregnant woman holding her belly
Source: Anna Hecker on Unsplash

New research suggests that the physiological ‘wear and tear’ of stress may affect a woman’s fecundability, ie her ability to fall pregnant within a menstrual cycle. The study was published in Acta Obstetricia et Gynecologica Scandinavica.

Allostatic load reflects multi-system physiological changes which occur in response to chronic psychosocial stress, reflecting a kind of ‘wear and tear’. The study investigated the link between female pre-pregnancy allostatic and time to pregnancy.

Reduced human fecundability not only results in infertility, it also creates social aging problems. Female fecundability is a complicated topic that can be influenced in many ways, including physical factors and psychological factors. Prior research tended to focus on the impact of chronic diseases, such as hypertension, diabetes and obesity. However, mental factors, including psychological pressure, anxiety and depression, could also potentially exert impact on female fecundability. Evidence supports that infertility may cause stress in many ways, but it is unclear whether stress causes infertility, or how stress and human fecundability interact.

The study assessed AL in 444 women who were trying to become pregnant. Women with higher allostatic load scores – based on nine indicators such as blood pressure, blood sugar, cortisol, noradrenaline, and cholesterol – were less likely to become pregnant within a year. For example, the women with an allostatic load score of 5–6 would have a 59% reduction of fecundability compared with those with scores of 0.

“What we found provides a new idea for preconception counselling. But obviously, how to objectively assess the stress is a complex scientific question, and how to intervene and reduce the impact of chronic stress is a burning problem, which are all things we need to study further,” said senior author Bei Wang, PhD, of Southeast University in Jiangsu, China.

Source: Wiley

Categories : Obstetrics & GynaecologyTags :

Trial Finds Linzagolix Safe and Effective for Uterine Fibroids

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A new, safer drug has been developed that could revolutionise the way clinicians treat some of the most common gynaecologic diseases including fibroids and endometriosis. A clinical trial published in the Lancet found that linzagolix, an oral drug that hinders oestrogen production, is an effective and customisable treatment for fibroids. Not only does linzagolix ease symptoms but also shrinks the fibroids themselves.

Professor Hugh S. Taylor, MD, co-author of the paper, said: “No treatments to date for fibroid growth are something I would ever want my patients to take for a prolonged period of time, as they did not treat the underlying cause of the problem. This is an extremely well tolerated class of drugs that can control fibroid growth. We’ve never had anything like that before.”

The suffering and inconvenience caused by uterine fibroids can have a serious impact on quality of life. “This can be an impediment to getting a good night’s sleep and being socially active, and it can even affect job performance,” said Prof Taylor.

As fibroids grow larger, they may begin putting pressure on other organs, resulting in a range of unpleasant symptoms including diarrhoea or constipation and frequent urination. Fibroids can also lead to difficulty in getting pregnant and increased risk of miscarriage. They are more common and aggressive in black patients.

Most drugs commonly used for uterine fibroids, including birth control pills, do not treat the fibroids themselves and just lighten or stop periods. And more aggressive drugs, although they treat the root of the problem are “overkill” Prof Taylor said. For example, leuprolide is an injectable drug that puts patients into a menopausal state by initially overstimulating hormonal receptors, which eventually shuts them down and completely blocks oestrogen production. Although the treatment addresses the fibroids, it also can initially exacerbate symptoms and cause harsh side effects. In more extreme cases, patients may opt for hysterectomy.

Promising clinical trial results

Linzagolix is an oral medication that works similarly to leuprolide by hindering hormone production. However, unlike its predecessor, it works by directly blocking the receptors instead of overstimulating them. The drug is also titratable, allowing reduction of oestrogen production without initiating menopause.

The new drug may however cause menopause symptoms such as hot flashes, with hormonal add-back therapy an option for mitigating these symptoms. For some patients, however, including patients with obesity, hypertension, or diabetes, this therapy has risks and may not be a suitable option. These conditions also tend to be more prevalent in Black patients. In this group, a lower dose of linzagolix without add-back therapy might be preferable.

To test the effectiveness of the drug, Prof Taylor’s team ran two large prospective, randomised, double-blind, placebo-controlled clinical trials known as PRIMROSE 1 and PRIMROSE 2. The studies enrolled patients suffering from substantial bleeding who were randomised to placebo or one of several different doses of the drug: 100mg alone, 100 mg with add-back therapy, 200mg alone, or 200mg with add-back therapy. Patients were followed for one year. The researchers considered the therapy successful if the patient’s bleeding was reduced by half and also stayed in what is considered the normal range.

Patients in all four treatment groups experienced a significant reduction in menstrual bleeding. The 200 mg with add-back therapy group worked with “amazing efficacy,” said Prof Taylor: the clinical trials showed a 75.5% response rate in PRIMROSE 1 and a 93.9% rate in PRIMROSE 2. Even the lower dose of the drug still showed promising results. There were greater than 60% response rates in both trials for the 100mg group with add-back therapy, and the 100mg group without add-back showed better than 50% response rates.

“What is interesting and unique about our trials, that has not been done with other drugs in this class, is that we used a low dose with or without hormones,” said Prof Taylor. “This is a great option for patients who experience severe menopause symptoms from the high dose or have a medical problem where they can’t tolerate hormonal add-back therapy.”

Changing the treatment of gynaecologic disease

Linzagolix is one of several in this new class of drugs in development for the treatment for common gynaecologic diseases. Prof Taylor was also involved in the 2017 clinical trial for elagolix, a medication designed to suppress endometriosis that has recently become available for patients.

Linzagolix has so far been approved in Europe. Taylor says drugs in this class will radically change how clinicians treat fibroids, and he hopes linzagolix will lead to a reduction in future hysterectomies once it becomes available.

“A good medical therapy is finally here for fibroids, and I predict that what was a very common operation will dramatically decrease within the next few years,” he says. “Reducing the need for hysterectomy is very important for patients who don’t want to undergo a major surgery, especially for younger people who may still want to preserve the potential of having children in the future.”

Source: Yale University

Categories : COVID Obstetrics & GynaecologyTags :

COVID Damages Placenta’s Immune Response

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In a study published in the American Journal of Obstetrics & Gynecology, researchers found that, if a woman is infected by SARS-CoV-2 during her pregnancy, the infection damages the placenta’s immune response to further infections – even if the infection was mild.

“This is the largest study to date of placentas from women who had COVID during their pregnancies,” said Professor Kristina Adams Waldorf, at the University of Washington School of Medicine and senior author of the study. “We were surprised to find that women who had COVID during their pregnancies had placentas with an impaired immune response to new infection.”

This finding, Prof Adams Waldorf added, “was the tip of the iceberg” in how COVID might affect foetal or placental development.

During the early stages of the pandemic, many thought that COVID did not appear to harm the developing foetus because there were so few babies born with COVID infection, she noted.

“But what we’re seeing now is that the placenta is vulnerable to COVID-19, and the infection changes the way the placenta works, and that in turn is likely to impact the development of the foetus,” Prof Adams Waldorf said.

“To date, the studies about how COVID might affect foetal or child development are very limited as the children are still very young,” noted co-author Dr Helen Feltovich, professor at Intermountain Healthcare.

“Our study suggests that babies born to mothers infected with COVID at any point during their pregnancy will need to be monitored as they grow up,” she said.

Studies led by Adams Waldorf have shown that pregnant women who contract COVID have a significantly higher mortality rate than those who do not contract COVID. Other studies have found that pregnant women are more likely to risk hospitalisations or preterm birth, according to the Center for Disease Control and Prevention.

It’s unknown how different COVID variants may affect the mother or foetus, Profs Adams Waldorf and Feltovich agree.

“Studying each of the variants in real time is really challenging because they just keep coming so fast, we can’t keep up,” Prof Adams Waldorf said. “We do know that the COVID Delta variant was worse for pregnant individuals, because there was a spike in stillbirths, maternal deaths and hospitalisations at that time.”

Regardless of the variant, Prof Adams Waldorf stressed taking precautions, such as vaccination and booster shots, limiting social contact a bubble of vaccinated individuals even if it means isolating for the duration of the pregnancy.

“The disease may be mild, or it may be severe, but we’re still seeing these abnormal effects on the placenta,” she said. “It seems that after contracting COVID in pregnancy, the placenta is exhausted by the infection, and can’t recover its immune function.”

In this study, a total of 164 pregnant individuals were studied, consisting of 24 uninfected healthy patients as a control group and 140 individuals who contracted COVID. Both groups delivered at about the same time, 37 to 38 weeks. Preterm birth occurred at nearly three times the rate with the patients with COVID when compared with those without. About 75% of the COVID patients had either asymptomatic COVID or mild symptoms.

Source: University of Washington School of Medicine/UW Medicine

Categories : Metabolic Disorders Obstetrics & GynaecologyTags :

Obesity and Diabetes in Pregnancy may Raise Child’s ADHD Risk

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A recent study has found that children born to women with gestational diabetes and obesity may have twice the risk of developing attention-deficit/hyperactivity disorder (ADHD) compared to those born to mothers without obesity. The findings, published in the Journal of Clinical Endocrinology & Metabolism, also found found that in women with a healthy weight gain during pregnancy, this risk increase was not seen.

ADHD is a growing problem. According to data from 2016-2019, 6 million children aged 3–17 years have received an ADHD. Maternal obesity is a major risk factor for ADHD in children, and roughly 30% of women have obesity at their first doctor’s visit during pregnancy, rising to 47% in women with gestational diabetes. Excessive weight gain during pregnancy in this population is a risk factor for children developing ADHD.

“Our study found pregnant women with obesity and gestational diabetes had children with long-term mental health disorders such as ADHD,” said Verónica Perea, MD, PhD, of the Hospital Universitari Mutua Terrassa in Barcelona. “We did not find this association when these women gained a healthy amount of weight during pregnancy.”

Studying 1036 children born to women with gestational diabetes, the researchers found that 13% of these children were diagnosed with ADHD. When compared to mothers without obesity, the researchers found children of women with gestational diabetes and obesity were twice as likely to have ADHD compared to those born to mothers without obesity.

Notably, this association was only seen in women with gestational diabetes, obesity and excessive weight gain during pregnancy. There was no increased risk of ADHD in children of women with gestational diabetes and obesity if the amount of weight these women gained during pregnancy was within the normal range.

“It’s important for clinicians to counsel their patients on the importance of healthy weight gain during pregnancy,” Perea said.

Source: The Endocrine Society

Categories : Obstetrics & GynaecologyTags :

Targeting Piezo1 Could Treat Preterm Labour

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Source: Pixabay

A serious neonatal health threat, preterm labour has long mystified researchers – and how does the uterus normally stay dormant, letting it stretch and expand during the 40 weeks it takes a foetus to grow? New research published in The Journal of Physiology suggests that a protein called Piezo1 keeps the uterus relaxed throughout gestation.

Preterm birth is a major cause of neonatal mortality and morbidity. The identification of Piezo1 in the uterus, and its role to maintain relaxation of uterus through stretch-activation during pregnancy, paves the way for drugs and therapies to be developed that could one day treat or delay preterm labour.

The muscular outer layer of the uterus is peculiar because it is the only muscle that it is not regulated by nerves and it must remain dormant for the 40 weeks despite significant expansion and stretch as the foetus develops into a baby. The researchers from University of Nevada USA studied tissue samples of the smooth muscle of the uterus to explore the mechanistic pathways to better understand the dynamics controlling the uterus, how pregnancy is maintained and what maintains quiescence until labour.

Stretching the uterus tissue, to mimic what happens during pregnancy, activates Piezo1 channels. This drives the flow of calcium molecules generating a signalling cascade that activates the enzyme nitric oxide synthase to produce the molecule nitric oxide. This Piezo1 cascade promotes and maintains the dormant state of the uterus.

Piezo1 controls the uterus by working in a dose-dependent manner, where channel activity is stimulated by the chemical Yoda1 and inhibited by a chemical called Dooku1 (Star Wars fans will no doubt recognise the inspiration behind these two names). When Piezo1 is upregulated, the uterus remains in a relaxed state. However, in preterm tissue, the expression of Piezo1 is significantly downregulated, ‘switching off’ the dormant signalling to the muscle, so the uterus contracts and initiates labour.

Professor Iain Buxton at the Myometrial Research Group at the University of Nevada said: “Pregnancy is the most impressive example of a human muscle enduring mechanical stress for a prolonged period. Finding Piezo1 in the muscular layer of the uterus means the uterus is controlled locally and is coordinated by a stretch-activated mechanism rather than hormonal influence from the ovaries or the placenta, which has been the assumption.

“It is troubling that there are still no drugs available to stop preterm labour. Thanks to the Nobel Prize winning discovery of Piezo proteins, which are responsible for how the body responds to mechanical force, and our investigation we are now closer to developing a treatment. Piezo1 and its relaxation mechanism provide a target for us which we could potentially activate with drugs. We need to test this with further studies and we hope to carry out clinical trials in the future.”

Contraction and relaxation were assessed in tissue samples compared for the following gestational periods: non-pregnant, term non-labouring, term labouring, preterm non-labouring and preterm labouring. The presence of Piezo1 channels was discovered using molecular tools while pregnant tissues contracting in a muscle bath were stimulated with Piezo1 channel activator and inhibitor to characterize the regulation of quiescence.

More research is needed to understand just how all the molecular signals and steps involved in the Piezo1 channel regulate uterus relaxation, and to identify other chemicals that may be involved.

Source: The Physiological Society