Why Do Miscarriages Occur?
The reason for miscarriage is varied, and most often the cause cannot be identified. During the first trimester, the most common cause of miscarriage is chromosomal abnormality – meaning that something is not correct with the baby’s chromosomes. Most chromosomal abnormalities are the cause of a damaged egg or sperm cell or are due to a problem at the time that the zygote went through the division process.
Other causes for miscarriage include (but are not limited to):
Hormonal problems, infections or maternal health problems
Lifestyle (i.e. smoking, drug use, malnutrition, excessive caffeine and exposure to radiation or toxic substances)
Implantation of the egg into the uterine lining does not occur properly
Factors that are not proven to cause miscarriage are sex, working outside the home (unless in a harmful environment) or moderate exercise.
What Are The Chances of Having a Miscarriage?
For women in their childbearing years, the chances of having a miscarriage can range from 10-25%, and in most healthy women the average is about a 15-20% chance.
An increase in maternal age affects the chances of miscarriage
Women under the age of 35 yrs old have about a 15% chance of miscarriage
Women who are 35-45 yrs old have a 20-35% chance of miscarriage
Women over the age of 45 can have up to a 50% chance of miscarriage
A woman who has had a previous miscarriage has a 25% chance of having another (only a slightly elevated risk than for someone who has not had a previous miscarriage)
Miscarriage Warning Signs