Fibroids are benign tumours of the uterus. These non-cancerous growths of the uterus often appear during childbearing years. Also called leiomyomas or myomas, they develop from the smooth muscular tissue of the uterus (myometrium).
They grow in various locations on and within the uterine wall itself or in the uterine cavity. Each starts as a single cell which divides repeatedly, eventually creating a mass of firm, white, gristly tissue that has a circular appearance.
Fibroids range in size from seedlings, undetectable by the human eye, to the size of a golf ball, to bulky masses that can distort and enlarge the uterus.
Fibroids may grow slowly or rapidly, or they may remain the same size, and some may shrink on their own. Many fibroids that have been present during pregnancy shrink or disappear after pregnancy, as the uterus goes back to a normal size.
As many as three out of four women have uterine fibroids sometime during their lives, and most do not have symptoms from their fibroids. They are usually discovered during a routine pelvic exam or when you go for your first prenatal ultrasound.
Pregnancy and fibroids
During pregnancy, hormone levels are high and pre-existing fibroids can grow rapidly. This means that fibroids not documented previously may suddenly be easy to see. The likelihood of your fibroids complicating your pregnancy and delivery is low.
Complications depend on the number, size and position of the fibroids. One of the main complications of fibroids in pregnancy is known as red degeneration and typically occurs between the 12th and 22nd week of pregnancy.
The mother can experience pain over the site of the fibroid involved and may develop a low fever. It occurs when the fibroids outgrow their blood supply, and so start to break down and degenerate. This cell death can be very painful. Usually symptoms resolve without any risk to the pregnancy.
What about in labour?
Worried that fibroids can interfere with normal labour? Well if the fibroids are well out of the pelvis or high up in the womb, there should be no ill effects.
Fibroids that distort the shape of your uterine cavity may cause your baby to lie in an unusual position that is not suitable for vaginal delivery. Also if the fibroid is low in the uterus and in the pelvic area itself, then it may potentially block the path of the baby and make a vaginal delivery more difficult.
Fibroids have little effect on the actual contractions. If the fibroid is out of the pelvis and the baby is in a normal position, then there is every chance of having a normal delivery.
If there are concerns about your fibroids being an issue during labour, then your doctor may discuss alternative birth options, meaning a caesarean birth.
Read more about: Recovering from a c-section
According to studies, labours are usually the same length and the vaginal birth rates aren’t different. Some feel that current literature tends to underestimate the prevalence of fibroids in pregnancy and overestimate the complications that they could potentially cause.
Haemorrhage after delivery can be an occasional problem as the uterus may contract slightly slower if there are fibroids present, and there may be an increased loss of blood after delivery.
Your doctor will be aware of any potential complications due to fibroids and will discuss necessary precautions with you to ensure that both you and your baby have a safe delivery, free of complications.
Most fibroids do not cause any symptoms, but some women who have fibroids may suffer from:
- Heavy bleeding or painful periods
- Bleeding between periods
- Feeling of fullness in the pelvic area (lower abdomen)
- Urinating often
- Pain during sex
- Lower back pain
Reproductive problems, such as infertility, having more than one miscarriage, or having early onset of labour during pregnancy.
Your doctor may discover you have fibroids at your regular gynae exam. If fibroids are suspected, he will do an ultrasound scan to confirm the diagnosis and document their size and position.