Uterine fibroids are noncancerous tumours, usually found in or around the uterus and occasionally the cervix. Fibroids often go completely unnoticed without any obvious symptoms; however depending on the size and the positioning of the fibroids, they can cause heavy menstrual bleeding, infertility or difficulties during pregnancy.
There are three main types of fibroids:
Intramural – Intramural fibroids are the most common type of fibroid. These are found within the muscular layers of the uterine wall.
Submucosal – Often protruding into the uterine cavity, this type of fibroid can obstruct the uterus and lead to heavy menstrual bleeding.
Subserosal – Found on the outer wall of the uterus and can cause pain as they grow by putting pressure on nearby organs.
Subserosal fibroids do not usually cause fertility problems, however submucosal fibroids are more likely to have an effect because of their position within the uterus. In some cases large intramural fibroids can alter the blood flow to the uterine lining and alter the shape of the uterine cavity. This distortion could prevent effective progress of the sperm and implantation.
During pregnancy there is an increase in female hormones, which can cause fibroids to grow more rapidly. In most cases, this doesn’t affect the pregnancy or cause any symptoms. However, in some cases this can cause a higher risk of miscarriage or premature labour. If the fibroids grow in such a way that they obstruct the birth canal, this can cause problems during labour or move the baby into a breech position. Both of these complications could result in a caesarean section delivery.
Treatment for fibroids is based on your individual situation, the severity of your symptoms and whether they are the cause of your infertility. You and your partner should both consider a thorough fertility evaluation and discuss the issue with your GP. Fibroids are not normally treated during pregnancy.