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Fibroids are non cancerous tumors, myomas or leiomyomas that grow in wall of the uterus (your womb).  There can be one or several of them and they can range in size from as small as pip to the size of a grapefruit.   They are present in approximately 10% of Pregnant Women (1). They are affected by hormones Estrogen & Progesterone and when these hormones are high during Pregnancy it an cause the Fibroids to grow in size.

They can grow:

  • Into the uterus – Submucosal
  • Within the wall of the uterus – Intramural 
  • On the outside of the uterus – Subserosal
  • On stalks like mushrooms out or into the uterus – Pedunculated

What Causes Fibroids?

The clear reason for Fibroids appearing is unknown but believed related to Genes and Hormones.   Factors that increase the likelihood of developing them include:

  • GENES – if your family has them there is a higher risk you may also develop them
  • AGE – they become more common with age up until menopause where they then usually shrink
  • ETHNICITY – study showed prevelence varied by race/ethnicity – 18% Africans, 8% Caucasian, 10% Hispanics (2)
  • DIET – a diet high in red meat and ham have been link with a higher risk and a diet high in vegetables linked with a lower risk of developing them (3)
  • OBESITY – there is a 2 to 3 times higher risk of developing them in an obese woman

What Are Symptoms of Fibroids?

Often there are no symptoms associated with Fibroids but some women can experience (4):

  • Heavy Bleeding – can lead to Anaemia
  • Feeling of fullness or pain in the lower stomach
  • Rounding of the lower abdomen
  • Gastrointestinal issues like diarrhea or constipation
  • Urinary issues like increased frequency, retentia or need to pee at night)
  • Lower back pain
  • Pain during sex

Fibroids & Pregnancy

For some women the fibroids grow during Pregnancy and for some they decrease in size.  Following birth they tend to reduce in size again.  The growth rate has been shown to usually most during the 1st trimester (5).    Most women with fibroids have normal pregnancies but having Fibroids does have an increased risk of developing problems during Pregnancy and Delivery.  It is believed that the increase in Estrogen & Progesterone can affect the Fibroids growth.     Your Obstetrician will be able to monitor your Fibroids during the Pregnancy and advise accordingly if any associated problems are happening which can include:

  • Need for a C-Section
  • Need for Fibroid Removal during birth
  • Baby’s position not being optimal for vaginal delivery
  • Preterm delivery
  • Placenta issues

Treatment Options

How Fibroids are managed will vary on individuals and their number and size of Fibroids.   Treatment options are limited during Pregnancy and it will be more about monitoring the growth of the Fibroids and then making the decision at a later stage on whether they need to be removed during the birth and whether being induced or having a C-section is indicated.

Some Questions to ask your Doctor?

It is good to get some answers from your Doctor so you can be more clear about your Fibroids and treatment options if required.

  1. How many fibroids do I have?
  2. Where are they located?
  3. What size are they?
  4. Is there a chance they will grow?
  5. What symptoms can I expect to have?
  6. How will the size of my fibroids be kept track of – which imaging or tests will be used?
  7. What treatments can I have during Pregnancy?
  8. How will the fibroids affect my birth delivery method?

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