Will fibroids affect my pregnancy?

By Joyce Nyakato

Many women tend to assume that fibroids  automatically cause infertility. Today, let's explore the relationship between fibroids and fertility.
 
After suffering abnormal bleeding during her periods, Sarah Nazziwa did a scan on her doctor’s requests. The results showed she had uterine fibroids. On hearing ‘fibroids’, the first thought that came to Nazziwa’s mind, just like for any other young woman, was infertility.
 
Fortunately, Nazziwa conceived and with the help of a doctor carried her child to full term and delivered via caesarean section.
 
According to Dr. Evelyn Nabunya, an obstetrician at Mulago Hospital, fibroids are a common occurrence among women. They are smooth non-cancerous tumours that grow in the uterus and can be as small as a pea or big enough to make one appear pregnant.
 
The cause of uterine fibroids is not known. However, their growth is linked to the hormone oestrogen, a hormone responsible for the growth of the uterus wall. In fact, fibroids never develop before the onset of menstruation when the female body begins producing oestrogen. Fibroids occur during the reproductive years, but peak during the 40s and 50s.
 
Dr. Busingye, a gynaecologist at Nakasero Hospital, adds that women who have not had children are also at a high risk of getting fibroids.
 
Do fibroids cause infertility?

The relationship between fibroids and infertility is what Dr. Busingye calls an ‘egg and chicken relationship’. Fibroids can be associated with infertility and vice versa.  The effect of a fibroid on a woman’s fertility depends on its size and location, he explains.
 
The uterus has three layers, that is, the inner lining called the endometrium; the wall of the uterus called the myometrium and the outer lining, called the serosa. Fibroids that grow on the outside wall of the uterus do not affect fertility, but can cause discomfort by compressing other organs, especially the bladder.
 
A fibroid which grows where the fallopian tube joins the uterus wall can compress the tubal opening, restricting the passage of sperms or eggs, thus compromising a woman’s fertility.

Studies show that fibroids in the muscle part of the uterus may cause a reduction of blood flow to the uterine lining making it difficult for an embryo to develop. Dr. Busingye, however, maintains that although fibroids may pose a fertility threat; women with fibroids can conceive and have normal deliveries.

Can fibroids co-exist with pregnancy?

Most women with fibroids have mild or no symptoms and do not need treatment. In such cases, gynaecologists encourage the women to have children, but doctors monitor the fibroids.
 
During pregnancy, Dr. Dan Murokora, a gynaecologist explains that women are exposed to high doses of progesterone. Progesterone, a hormone produced during pregnancy opposes the effects of oestrogen, a hormone responsible for the growth of the uterus.
 
When a woman is pregnant, the uterus expands to accommodate the growing baby and the fibroid also enlarges as it feeds off oestrogen.
 
Fibroids that grow under the uterine lining compete for space with the foetus, causing complications. They slightly increase the risk of miscarriages and preterm labour, where the uterus contracts, before it’s time to deliver the baby.
 
Mechanical obstruction of labour is another complication resulting from a fibroid in the cervix blocking the passage of the baby. In such cases, the baby is delivered via caesarean section, says Dr. Murokora.
 
Large fibroids sometimes undergo “red degeneration” during pregnancy, which occurs when a fibroid enlarges due to excess oestrogen and outgrows its blood supply.

The ‘starved’ part dies creating severe pain.  As part of the fibroid dies, the blood supply to the rest of the fibroid keeps it alive. The pain may reduce on its own or pain killers can be prescribed.
 
The uterus is a muscle that can contract and squeeze the bleeding vessels to stop bleeding. Fibroids do not allow the uterus to contract properly, so the blood vessels stay open longer, and a mother loses more blood after birth.
 
Can one get rid of fibroids?

The common method of removing fibroids is through surgery. “The surgery has potential complications, which must be weighed against the risk of not having the surgery at all,” says Dr. Busingye.
 
Such complications include the uterus bleeding from the sites where the fibroids were removed and it may be difficult to stop the bleeding. 
 
Surgery also creates a risk of scar formation around the uterus, predisposing one to deliver by caesarean section. “However, the surgery does not prevent the development of new fibroids,” he explains.
 
 Fibroid surgery has also been linked with a higher risk of uterine rupture in later pregnancy. Dr. Murokora agrees that surgery weakens the uterine wall to the degree that subsequent babies may need to be delivered via caesarean section.
 
Tips for women before surgery

According to Dr. Murokora, some benchmarks that gynaecologists consider before advising women to go for surgery to remove fibroids include:

• Fibroids cause infertility after other possible infertility causes have been ruled out.

• Large fibroids cause considerable discomfort.

• Fibroids cause heavy bleeding leading to anaemia.

• Fibroids are compressing other organs like the bladder.