Endometriosis is a condition where tissue similar to the lining of the uterus – called endometrial-like tissue – grows in other parts of the body, like the bowel and bladder. It can also affect reproductive structures like the ovaries and fallopian tubes.
In Australia, around 1 in 10 women suffer from endometriosis. Believe it or not, this means endometriosis is just as common as diabetes. However, because endometriosis commonly goes undiagnosed, this figure may be even higher.
It is important to note that most women who are diagnosed with endometriosis will have no trouble at all becoming pregnant – contrary to the common myth that ‘endometriosis equals infertility’. However, about 1 in 3 women with endometriosis will experience issues with fertility and may struggle to have a successful pregnancy without assistance.
How can endometriosis affect fertility?
There are a number of ways that endometriosis is thought to affect fertility:
Abnormal tissue growth
When endometrial-like tissue grows outside your womb (uterus), it can interfere with the function of other body parts. If this growth occurs within your pelvis, it may affect structures that play an important role in pregnancy – like the ovaries, fallopian tubes and uterus. This can disrupt their normal functions, hindering your ability to conceive.
Inflammation and scarring
One of the ways the body responds to the tissue damage caused by endometriosis is inflammation, leading to irritation and swelling of the affected tissue. While this inflammation represents the body’s attempt to ‘fight off’ the disease, it can also produce scar tissue – known as ‘adhesions’ – which can cause organs to stick to each other. These adhesions can damage the ovaries or fallopian tubes, block the movement of eggs through the fallopian tubes, or prevent sperm from entering the uterus.
Egg quality and quantity
Some experts believe that substances released during inflammation may be toxic to a woman’s eggs, affecting their quality. Hormone imbalances in the ovary (caused by endometriomas – cysts that form in or on the ovary in women with endometriosis) may also affect the development and quality of eggs. Women with endometriomas also typically have fewer eggs (low ‘ovarian reserve’). Scar tissue caused by endometriosis may also starve the ovaries of blood flow and oxygen, resulting in eggs that don’t mature properly. This may affect the ability of your eggs to fertilise, implant and develop in a healthy way.
Medical treatments used to control your symptoms
You can find a summary of common treatments for endometriosis here. Most of these treatments are designed to control symptoms by stopping ovulation, thereby switching off the hormones that stimulate abnormal tissue growth. While these treatments can help control symptoms, they also act to temporarily decrease your fertility. Hence, you will need to pause these kinds of treatments when you are ready to get pregnant.
If I have endometriosis, when should I have my fertility tested?
If you have endometriosis and are now ready to become pregnant, I advise a consultation with your gynaecologist to discuss stopping any medical treatment you may be on (e.g. oral contraceptive) and to identify ways you can optimise your fertility. If you have been seeing your gynaecologist for a long time, he/she will have a good understanding of the severity of your endometriosis (including what pelvic structures are affected from any previous imaging studies/laparoscopes) and will be able to manage your expectations accordingly.
In general, if you have been unable to become pregnant after trying for 6 to 12 months, I recommend a fertility assessment. Women who are ≥ 35 years old should seek help earlier (after 6 months of trying), as age is also a risk factor for fertility issues.
It’s also important to recognise that endometriosis may not be the reason you are having trouble getting pregnant. For example, there are other health conditions, as well as lifestyle factors (such as diet and exercise), that can also affect your ability to conceive. Similarly, it’s prudent that we also assess your partner’s fertility to rule out any male-related fertility issues.
What treatments can aid fertility?
If your assessment does point to endometriosis as the source of your fertility issues, there are a number of treatment options available, depending on what specific problems your endometriosis is causing.
Surgery to remove some of the abnormal tissue and adhesions caused by endometriosis has been shown to improve fertility in women with mild to moderate disease.1 Laparoscopic (keyhole) surgery is the most common method for removing this tissue. After surgery, the best chances of conceiving are during the first few months, so women should strive to become pregnant as soon as possible (before the abnormal tissue or scar tissue has time to recur).
If surgery alone does not lead to a successful pregnancy, IVF may be an option for you. One study found that women with endometriosis who underwent both surgery and IVF were more likely to achieve a pregnancy than women who only had surgery (56.1% vs. 37.4% respectively).2 In severe cases, where egg quality or quantity is an issue, you might need to consider using donor eggs – this is more likely if you are also over 40.
There is an average delay of 7–12 years from when a woman first presents with symptoms of endometriosis to when she receives a diagnosis – probably, in part, because both women and doctors tend to ‘normalise’ the symptoms of endometriosis (like painful periods). However, a delayed diagnosis does mean that the disease is more likely to have progressed and caused damage to reproductive structures.
Hence, the best way to maintain fertility is early detection and treatment to help limit the abnormal tissue growth and subsequent damage it causes. Early detection also provides women with additional options. For example, if you are diagnosed at a younger age, you may decide to freeze some of your eggs ‘just in case’, enabling you to focus on symptom control until you are ready for a pregnancy. Then, should fertility issues arise later in life, you have some eggs safe-guarded if you decide to go down the path of IVF.
Other fertility treatments (including those used by women without endometriosis) may also be helpful. You can read about these options in more detail here. For most women, a combination of medical treatment, surgery and lifestyle change will help maintain and optimise fertility in the setting of endometriosis.
Can pregnancy cure endometriosis?
A common myth is that pregnancy cures endometriosis. Hormonal changes during pregnancy may temporarily reduce abnormal tissue growth and improve your symptoms. However, once hormone levels normalise after pregnancy and breastfeeding, you may find that your symptoms return.
If you have been diagnosed with endometriosis, be reassured that not all women in your position experience fertility issues. However, it is best to seek specialist advice as early as possible, with the aim of preventing fertility from becoming an issue down the track.
- Marcoux S, Maheux R, Bérubé S. Laporoscopic surgery in infertile women with minimal or mild endometriosis. Canadian collaborative group on endometriosis. N Engl J Med.1997 Jul 24;337(4):217-22. (Accessed online 30 January 2019) Available at https://www.ncbi.nlm.nih.gov/pubmed/9227926 ↩
- Coccia, M. Elisabetta et al. Endometriosis and infertility. European Journal of Obstetrics and Gynecology and Reproductive Biology, Volume 138, Issue 1, 54-59. (Accessed online 30 January 2019) Available at https://www.ncbi.nlm.nih.gov/pubmed/18243485 ↩