This section covers recurrent miscarriage in the first trimester of pregnancy (first 12 weeks). 1 in 100 couples trying for a baby experience recurrent miscarriage, which is defined as 3 or more miscarriages in a row. This can be a very unhappy, lonely and distressing experience.
Investigations are not usually offered to women after 1 or 2 miscarriages; this is due to statistics showing the chances of a successful pregnancy next time are extremely good, suggesting the miscarriage was due to chance rather than an underlying cause. If a woman has 3 or more miscarriages in a row, it is more likely that there is an underlying cause, so referral to a dedicated Recurrent Miscarriage Clinic is advisable.
There are a few risk factors linked to recurrent miscarriage in the first trimester. They include maternal age, number of previous miscarriages, heavy alcohol consumption, obesity, anti-phospholipid syndrome, immune factors, endocrine factors, infective agents, baby chromosomal abnormalities and parental chromosomal rearrangements.
Throughout pregnancy blood flow between the mother and baby is very important. There are a large group of antibodies that may affect the blood supply in the placenta or cause abnormal implantation of the placenta in the wall of the uterus. 15% of women who experience recurrent miscarriage have high levels of these antibodies.
Some people have blood that clots too easily because of abnormalities inherited from their parents.
A high thyroid imbalance in a woman not diagnosed or poorly controlled are associated with miscarriage. The same with a woman not diagnosed or poorly controlled with diabetes in the first 12 weeks of pregnancy. If properly controlled, both medical conditions would not cause a miscarriage.
In general, infection is not thought to be a cause of first trimester recurrent miscarriage. However, severe infection at the time of miscarriage could be the cause. Treatment is very simple and easy in the form of antibiotics.
Baby chromosomes carry genetic information. Everyone has 23 pairs of chromosomes making 46 in total. When you conceive, the baby receives half its chromosomes from the mother and half from its father. In approximately 50% of miscarriages, it is thought that the baby chromosomes had a problem; it happens soon after conception (when the sperm meets the egg), therefore some recurrent miscarriage clinics will offer chromosomal analysis of the pregnancy tissue after a miscarriage. The older you are the more likely this can happen.
A very small amount of people (1.9%) can have a chromosomal rearrangement called a balanced translocation. This does not cause a problem for the person but can be passed on the baby, which can cause an unbalanced translocation, which means the baby does not have enough or too much genetic information. Routine testing of the woman or man’s chromosomes are not routinely offered.
When you are ready to try for another pregnancy, it is better that your body is ready, therefore it is important to have your health in good order. Having a healthy weight, not smoking and not consuming large amounts of alcohol will have a positive impact on your health. Some clinics will check your vitamin D, calcium and iron levels so that if you are found deficient in these areas they can be treated before you get pregnant. It is also advised you are taking folic acid pre-conceptually.
If there is no explanation for the recurrent miscarriages, the couple have a very good chance of having a child, without any treatment, if offered supportive care alone in a dedicated Recurrent Miscarriage clinic with specialist trained staff.
Not everything is known about why some couples miscarry, therefore carrying out research is very important. Research can help health professionals find reasons and potential treatments for couples experiencing recurrent miscarriage.