Each year in the UK, hundreds of thousands of women are affected by miscarriage. A miscarriage is when a pregnancy ends before 24 weeks. In the vast majority of cases, there is no way of preventing a miscarriage.

Having a miscarriage does not mean that you won't be able to get pregnant again, and most women go on to have a successful pregnancy.

Causes of Miscarriage

The most common reasons include the following:

An abnormal fetus causes almost all miscarriages during the first three months of pregnancy (first trimester). Problems in the genes are responsible for an abnormal fetus and are found in more than half of miscarried fetuses. The risk of defective genes increases with the woman's age, especially over if she is older than 35 years.

Researchers have long known that during times of stress, the brain releases several hormones -- including one called corticotropin-releasing hormone (CRH). In past research, women who deliver prematurely or have low-birth-weight babies were often found to have high levels of CRH in their bloodstream, and other studies show a greater risk of miscarriage in women reporting stress. CRH is a hormone the brain secretes in reaction to physical or emotional stress, and it is also produced in the placenta and the uterus of a pregnant woman to trigger uterine contractions during delivery.

Fetal chromosomal abnormalities are the commonest cause of sporadic miscarriage affecting more than half of all early miscarriages. This may be due to abnormalities in the egg, sperm or both. The usual chromosomal pattern is 46 chromosomes which are arranged in 23 pairs, one of these pairs is called sex chromosomes, females will have two X chromosomes and males will have one X chromosome and a Y chromosome. The genes we all have are lined up along the chromosomes.

Trisomy: It is a type of chromosomal abnormality where there will be three chromosomes of one type rather than normal pair. This results in an embryo with 47 chromosomes instead of 46 and will either abort, or develop into a baby with congenital abnormalities. It is more common as reproductive age increases and the abnormalities are not very likely to recur.

Monosomy: In this type, you will notice missing of one chromosome. This condition is called Turner's syndrome where pregnancies will carry on with only one X chromosome.

Premature Rupture of Membranes and Early Labor

Many miscarriages begin with cramping and labor-like symptoms, but true PROM and Early Labor are usually associated with babies that are in the second or third trimester. Early labor can often be treated with drugs that relax the uterus and women are placed on bed rest either at home or in the hospital.

Sometimes, however, the baby comes anyway. This is one of the most traumatic of losses, technically a stillbirth and not a miscarriage after 20 weeks, because you will hold and see your baby and beg him or her to breathe. For some women, the baby will even be born alive, but only live for a few minutes, hours or days. There really is nothing harder in life than this.