It is often impossible to determine the exact cause for a miscarriage, though it is believed that miscarriages that occur during the first trimester are due to a chromosomal abnormality. Most abnormalities are caused by a damaged egg or sperm cell or a problem that occurred when the zygote went through the division process. A miscarriage can also be caused by hormonal problems, infections or health problems experienced by the mother, maternal age, maternal trauma or improper implantation of the egg into the uterine lining. Certainly, smoking, drug use or excessive consumption of caffeine can also lead to miscarriage.
Because female fertility decreases with age, it’s not surprising to learn that the chances of having a miscarriage increase with maternal age. Women under the age of 35 have a 15% chance of a miscarriage while women between the ages of 35 and 45 have a 20 – 35% chance of having a miscarriage.
After experiencing a miscarriage, many women want to know when they can start trying again. The answers vary. Some doctors recommend waiting until the woman has had at least one period before trying again, primarily because it is then easier to calculate dates in the next pregnancy. There is some evidence that conceiving in the first six months after a miscarriage lowers the risk of another one.
According to Dr. Enrique Schisterman of the Eunice Kennedy Shriver National Institute of Child Health and Human Development in the US, “Our data suggest that women who try for a new pregnancy within three months can conceive as quickly, if not quicker, than women who wait for three months or more.” This data comes from a study of nearly 1,000 couples after an early pregnancy miscarriage. Of these couples, 765 couples tried to get pregnant again within three months; 77% eventually gave birth.
The answer to the question “when to try again” seems to vary, but the common thread that runs through each answer is that “when to try again” really depends on the couple themselves and when they feel they are emotionally ready to give it another try.