New genetic causes linked to abnormal pregnancies and miscarriages

image credit: healthywomen.org

A team of scientists at the Research Institute of the McGill University Health Centre (RI-MUHC) and McGill University have identified three genes responsible for recurrent molar pregnancies, a rare complication that occurs when a non-viable pregnancy with no embryo implants in the uterus. The results of this study could have important implications, since until now very little is known about the genetic causes of all forms of fetal loss. Their study has recently been published in The American Journal of Human Genetics.

In Quebec, molar pregnancy occurs in about one in every 600 pregnancies, and half of these are characterized by a total absence of maternal chromosomes. Due to an imbalance in the number of chromosomes supplied from the mother and the father, the placental tissue grows abnormally and forms a tumour, leading to a malignant cancer in approximately 15 to 20 per cent of cases. Molar pregnancy is the most common form of all placental diseases (or trophoblastic diseases).

"Our findings add three new genes to the list of mutations leading to fetal loss and will allow for more DNA testing for patients in order to prevent the recurrence of molar pregnancies and provide better genetic counselling and management for couples," says lead study author Dr. Rima Slim, who is a researcher in the Child Health and Human Development (CHHD) Program at the RI-MUHC and an associate professor of Human Genetics and Obstetrics and Gynecology at McGill University.

Can a single missing gene lead to miscarriage?

image credit: medicalnewstoday.com

A single gene of the mother plays such a crucial role in the development of the placenta that its dysfunction leads to miscarriages. Researchers from the Medical Faculty of Ruhr-Universität Bochum (RUB) have observed this in so-called knockout mice that were specifically modified for this purpose. These mice lack the gene for the transcription factor Math6. By conducting further analyses, the research team is now hoping to gain new insights into the role the gene plays in recurrent miscarriage in humans. The researchers headed by Professor Beate Brand-Saberi published their results in the journal Scientific Reports on 9 October 2018.

Embryos die due to placenta problems

Transcription factors regulate the expression of downstream genes. Math6 plays a significant role in a number of organs during prenatal development as well as in the adult organism. The knockout mice generated at RUB lack the gene for the transcription factor Math6. “Considering the consequences caused by the lacking gene, conclusions can be drawn regarding its function,” explains Beate Brand-Saberi, Head of the Department of Anatomy and Embryology.

Study disputes link between uterine fibroids and miscarriage risk

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"A 10-year study, led by Vanderbilt University Medical Center professor of Obstetrics and Gynecology Katherine Hartmann, M.D., Ph.D., disrupts conventional wisdom that uterine fibroids cause miscarriages.

The results of study appear June 7, 2017 in the American Journal of Epidemiology.

"We find women with fibroids are not at increased risk of miscarriage," said Hartmann. "Women with fibroids had identical risk of miscarriage as women without fibroids when taking into account other risks for pregnancy loss. We were stunned."

Fibroids are common benign uterine masses that can distort the external and internal contour of the uterus. Changes in uterine architecture and other local effects of fibroids have been implicated in prior research as a risk factor for miscarriage, said Hartmann.

"This is great news for women. Our results challenge the existing paradigm and have potential to reduce unnecessary surgical intervention," she said.

The study, "Prospective Cohort Study of Uterine Fibroids and Miscarriage Risk," included women from eight urban and suburban communities in three states to achieve a racially diverse cohort of women planning pregnancies or in the early weeks of pregnancy. Each woman in the Right from the Start study had a standardized ultrasound for fibroids to determine presence, number, size and location in the uterus..."

Learn more:

https://www.sciencedaily.com/releases/2017/06/170607163025.htm

'Morning sickness' linked to lower miscarriage risk

via pregnancyandbaby.com

"Morning sickness is linked to a lower risk of miscarriage, according to research out Monday that suggests a woman's nausea and vomiting early in pregnancy may have protective effects for the fetus.

Between 50 and 80 percent of pregnant women report feeling nauseous or throwing up during their first trimester, said the findings in the Journal of the American Medical Association (JAMA) Internal Medicine.

The condition is often called "morning sickness," though it can affect women at all times of the day and night.

In a study of 797 women, nausea and nausea with vomiting were associated with a 50 percent to 75 percent reduction in the risk of pregnancy loss, said the report, led by Enrique Schisterman of the US National Institute of Child Health and Human Development.

The women had all had one or two prior pregnancy losses. They tracked their nausea symptoms in a diary, and their pregnancies were confirmed by urine tests.

Prior research has also suggested that nausea and vomiting are linked to a lower risk for pregnancy loss.

Some experts believe nausea may encourage a healthy pregnancy by leading women to eat less, thereby reducing the risk of exposing the fetus to toxins.

The reduction in food intake also appears to lower levels of circulating insulin and encourage growth of the placenta, research has shown.

The new study did not delve into reasons why nausea and vomiting may lower the risk of miscarriage..."

Learn more:

http://medicalxpress.com/news/2016-09-morning-sickness-linked-miscarriage.html

Scientists identify protein which could improve treatments for recurrent miscarriages

via dujs.dartmouth.edu

"Scientists at the University of Sheffield have identified a protein, involved in the development of the human placenta, may also help embryos implant in the womb - something which could improve treatments for recurrent miscarriages and pre-eclampsia.

The pioneering study shows that a protein called Syncytin-1, which was the result of a viral infection of our primate ancestors 25 million years ago, is first secreted on the surface of a developing embryo even before it implants in the womb.

This means the protein is likely to play a major role in helping embryos stick to the womb as well as the formation of the placenta.

This fundamental understanding of the earliest stages of human embryo development is crucial for improving current treatments for a variety of stressful complications during pregnancy such as recurrent miscarriages, foetal growth restriction syndrome and pre-eclampsia - a life-threatening condition of elevated maternal blood pressure during pregnancy.

Professor Harry Moore, Co-Director for the University's Centre for Stem Cell Biology and lead author of the study, said: "Recurrent miscarriages, foetal growth restriction syndrome and pre-eclampsia are all significant and very stressful complications of pregnancy..."

Read more here:

http://medicalxpress.com/news/2016-05-scientists-protein-treatments-recurrent-miscarriages.html

Lack of stem cells to blame for recurrent miscarriages

via medicalschool.tumbler.com

"Scientists at the University of Warwick have discovered that a lack of stem cells in the womb lining is causing thousands of women to suffer from recurrent miscarriages.

The academics behind the breakthrough are now to start research into a treatment which they believe could bring hope to those who have suffered failed pregnancies.

Professor of Obstetrics & Gynaecology, Jan Brosens led the team who unearthed the link between stem cells and miscarriage. He said: "We have discovered that the lining of the womb in the recurrent miscarriage patients we studied is already defective before pregnancy.

"I can envisage that we will be able to correct these defects before the patient tries to achieve another pregnancy. In fact, this may be the only way to really prevent miscarriages in these cases."

The team found a shortfall of stem cells is the likely cause of accelerated ageing of the lining of the womb which results in the failure of some pregnancies.

Miscarriage is the most common cause of loss; between 15-25% of pregnancies end in miscarriage and one in 100 women trying to conceive suffer recurrent miscarriages, defined as the loss of three or more consecutive pregnancies..."

Learn ore here:
http://medicalxpress.com/news/2016-03-lack-stem-cells-blame-recurrent.html

Making sense of a miscarriage

via todaychristianwoman.com

"..Miscarriages are so common – one in five pregnancies end up in a miscarriage," says Arri Coomarasamy, a professor of gynaecology at the University of Birmingham. Empathy is soothingly evident in his voice as I come to the end of my story.

The one in five figure is often quoted. Sometimes it creeps up to one in four. This is because it's difficult to determine how many miscarriages take place. In the UK, miscarriage means the loss of a pregnancy during the first 23 weeks (any later and it is called stillbirth). But it often occurs before a woman even realises she's pregnant, and most of the time – 85 per cent – it is in the first 12 weeks of pregnancy.

That has given us clear social guidelines. The "12-week rule" warns against telling anyone you're pregnant until the end of the third month. It anticipates the risk of loss, even sets us up to tentatively expect miscarriage during the early stages of pregnancy, but this silence doesn't make it any easier if it does happen.

A recent survey of over 6,000 women who had had a miscarriage, conducted by the charity Tommy's, found that around two-thirds found it hard to talk about. The same number felt that they couldn't discuss their miscarriage with their best friend. A third didn't feel that they could even talk to the father about it..."

Read the whole article here:
http://medicalxpress.com/news/2016-03-miscarriage.html