Pregnancy Bliss | Reproductive Health Answers
Endometriosis, pelvic pain and sub-fertility
By Dr J Kabyemela, MD
Many women will not have heard of the condition endometriosis unless personally affected or, at least a loved one has been diagnosed with the condition. Yet, endometriosis is a fairly common condition affecting millions of women worldwide to varying degrees of severity.
What is endometriosis?
The womb cavity is lined by a tissue called ‘endometrium’. The endometrium is the tissue that, under the influence of hormones estrogen and progesterone grows and breaks down every month manifesting as menstruation. It is also the tissue where, in a successful conception, the fertilised egg implants. Endometriosis is a condition where bits of this tissue are found outside the womb cavity. In a typical case of endometriosis, several ‘islands’ of this tissue would be found inside the pelvic cavity, typically behind the uterus or on the ovaries. In some cases, there is only one or two lesions to be seen. In other cases, the whole pelvic cavity is covered in endometriotic lesions.
Endometriotic cysts (‘chocolate’ cysts)
As mentioned earlier, ovaries are a common site for endometriosis. The endometriosis
could be on the surface of the ovary but often the endometriosis will be within the
ovary leading to format
ion of a cyst inside the ovary. The cyst is descriptively
known as a ‘chocolate cyst’. The name comes from the fact that the cyst will be filled
with old thick dark brown blood similar to chocolate mousse. If there was some doubt
about the nature of an ovarian cyst, the finding of this material virtually confirms
the diagnosis of endometriosis (see image, right).
How common is endometriosis?
It is estimated that up to 10% of women in the child-bearing age are affected by endometriosis (to varying degrees) at any one time. It is impossible to be accurate because a large proportion of women affected by the condition are completely symptom-free. Moreover, the only way endometriosis can be confirmed is by an invasive procedure, at least in the form of a laparoscopy to directly visualise the lesions. A biopsy can sometimes be used as a confirmatory test but this is rarely necessary. There is no blood test or imaging investigation that can be used to diagnose endometriosis.
Endometriosis appears to affect women of all races equally. It affects women in the child-bearing age and is not seen in pre-pubertal girls. Girls as young as 12 or 13 have been diagnosed with endometriosis a mere few months after they start having periods. This is uncommon. It is mostly diagnosed in women in their 20s and 30s. Endometriosis resolves after the menopause.
Why endometriosis develops remains a mystery to date. There are many theories put forward over the last 100 years or so but none seem to fully explain the origins of the condition. However, there are a number of risk factors which make it more likely for some people to be affected by the condition.
Risk factors for endometriosis:
- Family history: First degree relatives (daughter or sister) of a person affected have a 10 times higher risk of developing endometriosis compared to the general population
- Early menarche: If a girl starts having her periods at a significantly earlier age than her peers, she is at higher risk of endometriosis
- Heavy and/or prolonged periods: Menstrual loss is subjective. However, overall, women who report having heavy periods and/or periods which are typically prolonged, lasting more than a week each month, are known to have a higher than average risk of having endometriosis.
- Delayed childbirth: Women who start a family late, typically beyond their 30th birthday, are at higher risk of endometriosis
- Nulliparity: Having no children is a risk factor for endometriosis. In fact, there is an inverse relationship between risk of endometriosis and number of children. The more children the woman has, the lower the risk of endometriosis.
- Anatomic defects of the uterus and fallopian tubes: In a small number of patients, the risk of endometriosis has been associated with abnormalities of the reproductive organs (uterus and tubes)
In many women affected by endometriosis, no apparent risk factor can be identified.
Clinical presentation of endometriosis
The commonest clinical feature of endometriosis is lower abdominal or pelvic pain. Pain due to endometriosis is typically cyclical, usually occurring during menstruation. Many, probably most, endometriosis sufferers are remarkably pain-free during the rest of the month. However, some will report having on-going low-grade pain throughout the month with exacerbations, sometimes dramatic, at the onset of menstruation.
Pain with sexual intercourse is another common presentation with endometriosis. The typical history will be that the pain that a woman may not have had before suddenly starts even though there has been no change of partner. It is typically (but not always) felt on deep penetration and in certain positions only. The pain can be so bad as to lead the affected woman to avoid sex altogether.
Fertility problems: Some women affected by endometriosis may encounter fertility problems. These could range from inability to conceive to increased risk of miscarriage. Severe endometriosis is accompanied by marked distortion of pelvic structures especially the fallopian tubes. The mechanical distortion may be so bad that it results in blockage of the tubes. However, this is not the only issue when it comes to endometriosis-related sub-fertility. It is believed that the inflammatory reaction brought about by endometriosis causes a release of chemicals in the pelvis which creates a hostile environment for normal conception to take place. The latter is believed to be the main factor in endometriosis-related sub-fertility. Up to 4 in 10 women with endometriosis will present with sub-fertility.
The clinical features mentioned above are the commonest but not the only ones associated with endometriosis. Other, less common clinical features of the condition include:
- Lower back pain (especially around the time of menstruation)
- Recurrent painful micturition. Some women may report getting pain when passing water; again, this tends to occur around the time of menstruation with spontaneous resolution afterwards.
- Rectal bleeding: This is a very uncommon symptom but when it occurs as a cyclical feature coinciding with a woman’s period; it is almost confirmatory of the diagnosis. This may be accompanied by painful defecation. The medical term for this symptom is ‘dyschezia’.
- Other non-specific symptoms that could be reported in endometriosis include a feeling of bloatedness, nausea and even vomiting during menstruation.