What causes a Miscarriage?

You can be certain your miscarriage was NOT caused by bending, stretching, carrying heavy weights, digging the garden, exercising or having sex, otherwise there would be many more.

Unfortunately most women never find out the cause of their miscarriage. There is nothing that can be done to save a non-viable pregnancy.

The most common reasons are:

• Many miscarriages are due to chromosomal problems or genetic abnormalities (50%)and are by chance. Something goes wrong during or soon after conception and the part of the pregnancy that grows into the baby fails to develop. This is known as 'afoetal pregnancy' or 'blighted ovum'.
• Something may be wrong with the placenta.
• The fertilised egg may implant in the wrong place.
• Endometriosis, this can double the chances of miscarriage.
• Hypothyroidism, this has now been connected to late miscarriage but if known about or tested for it can be dealt with.
• Diabetes. The anti-diabetes drug 'Metformin' appears to reduce the likelihood of early miscarriage.
• 'Anti phospholipid syndrome' is an antibody that causes blood clots to form in the placenta, which causes repeat miscarriages. Treatment with Aspirin, Clexane or Heparin works in many cases. Subsequent pregnancies also require treatment.
• "NK' Cells. These are responsible for protecting us from invasion by bacteria, viruses and foreign bodies, and rejecting organ transplants. The foetus contains foreign genetic material coming from the father, but in normal circumstances it does not get rejected. However, in some women these NK cells may reject the foetus and cause a miscarriage either by being high in numbers or by abnormal hostile activity. This problem, as most autoimmune disorders, can switch on and off, therefore some of the women may have one or more normal pregnancy outcomes as well as recurrent miscarriages. Women with CD16/56 NK cells in excess of 12% or 0.2 absolute number are at risk of miscarrying.
• The mother's immune system or hormone levels may effect the pregnancy. She may be sick, badly injured, under too much stress, have a deformed uterus, a weak cervix or still have an intrauterine contraceptive device (IUCD) inside the uterus, or an infection.
• Environmental pollution may be a cause.
• The consumption of alcohol, cigarettes and recreational drugs is linked to higher rates of miscarriage.
• A hard blow to the stomach.
• Given that women are born with their life supply of eggs, maturing at puberty, by 35 these eggs have become older and less viable.
• Under-nourishment at conception.
• Caffeine is now also being linked to miscarriage. The American FDA recommend no more than 300 mg per day which equates to;
  - 6 cups of tea or 4 cups (3 mugs) of coffee.
  - Soft drinks, energy drinks and chocolate contain caffeine and should be restricted.
• Small fibroids may increase miscarriage risk;
  According to early findings from a pilot study done by researchers at the University of North Carolina at Chapel Hill, America, it appears the presence of fibroids is uniformly associated with and may increase miscarriage. (Fibroids are benign muscle tumours of the uterus.) It's estimated they affect more than one in five women of reproductive age, and early results indicate that women with small fibroids (more so than larger sfibroids) have a 55% increased risk of pregnancy loss.

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