It is very unlikely that you will ever know the true cause of a single miscarriage, but most of them are due to the following issues:
• ABNORMAL FETUS
The most common cause of miscarriages in the first few months is a single abnormal development of the fetus, often due to chromosome abnormalities. “It’s not like the baby is fine one minute and suddenly dies the next,” says Professor James Walker, a professor of obstetrics and gynecology at the University of Leeds.
“These pregnancies fail from the start and were never destined to succeed.” Most miscarriages like this happen at eight weeks, although bleeding may not start until three or four weeks, which is worth remembering for subsequent pregnancies. “If a scan shows a healthy heartbeat after eight weeks, you have a 95 percent chance of a successful pregnancy,” says Professor Walker.
• HORMONAL FACTORS
A hormonal blip can cause a sporadic miscarriage and never be a problem again. However, a small number of women with long cycles and irregular periods may experience recurrent miscarriages because the lining of the uterus is too thin, making implantation difficult.
Unfortunately, hormone treatment is not very successful.
‘There used to be a trend for treatment with progesterone, but tests show that this really doesn’t work,’ warns Professor Walker. ‘There is some evidence that injections of HCG (human chorionic gonadotropin, a hormone released during early pregnancy) can help, but it is not the solution for everyone.’ Treatment should be started as soon as pregnancy is confirmed, at about four or five weeks.
For women over 40, one in four women who become pregnant will have a miscarriage. [One in four women of all ages miscarry, but these figures include women who don’t know that they are pregnant. Of women who do know that they’re pregnant, the figure is one in six. Once you’re over 40, and know that you’re pregnant, the figure rises to one in four]
• AUTOIMMUNE BLOOD DISORDERS
About 20 percent of recurrent miscarriages suffer from lupus or a similar autoimmune disease that causes blood clots to form in the developing placenta.
A simple blood test, which may need to be repeated several times, can reveal whether or not this is the problem. ‘One negative test doesn’t mean a woman is fine,’ warns Mr Roy Farquharson, gynecologist consultant who leads early pregnancy. ward at Liverpool Women’s Hospital.
Often pregnancy can be a trigger for these conditions, so testing should be done as soon as possible,” he adds. But it can be easily treated with low-dose aspirin or heparin injections, which help thin the blood and prevent blood clots. – a recent trial also showed that women do equally well on both. “We have a 70 percent live birth rate in women treated for these conditions,” says Dr. Farquharson, “which is outstanding.”
• OTHER CAUSES
Although uterine abnormalities, such as uterine fibroids, can cause miscarriage, many women have no problem carrying on with a pregnancy. An incompetent cervix can also cause a miscarriage around 20 weeks.
While this can be treated with a special suture in the cervix, studies suggest it’s not particularly successful, although it may delay labor by a few weeks. a small number of pairs.
A procedure known as preimplantation genetic diagnosis can help. After in vitro fertilization (IVF), a single cell is taken from the developing embryo and tested for the gene defect. Only healthy embryos are then placed back in the uterus.
It’s an expensive and stressful procedure — and pregnancy rates are usually quite low — but for some, it’s preferable to repeated miscarriages or a genetically abnormal baby.