Adenomyosis, an estrogen fuelled inflammatory condition, is where endometrial tissue exists in the myometrium (muscular layer of the uterus) and grows into the uterine wall.
For more information on adenomyosis, read the post about diagnosis of adenomyosis and treatment of adenomyosis.
Upon diagnosis, you might have more questions than answers about the condition and how it affects your life. I would guess that most people probably haven’t really heard of adenomyosis until they are given the diagnosis. Many will go to Google and do their own research about what this means for them. If having children is something you see in your future, and this can be a really isolating and stressful time. Scarily enough, there is even less known about adenomyosis than endometriosis! Some of the main concerns you may have will be around management of pain, heavy periods and how the condition might affect your chances of conceiving and achieving a healthy pregnancy to term.
Many doctors and researchers still do not know how adenomyosis occurs, and how it might affect fertility. Most researchers can’t even agree on what the actual prevalence of adenomyosis is. That just shows how much further we need to go with diagnosis and treatment! Whilst many women can have both endometriosis and adenomyosis, there is more known about how endometriosis affects fertility. These include structural differences from endometrioma, comorbidity with other uterine conditions (e.g., fibroids and polyps) and development of adhesions.
Today, we explore some of the potential reasons and theories in the research around how adenomyosis may affect your fertility and subsequent pregnancy.
Let’s jump into it!
Impact on Fertility
1. Uterine Junctional Zone Thickness (JZ Thickness)
Implantation
In adenomyosis, the uterus may be less receptive to implantation. The junctional zone of the uterus is the area between the endometrium and inner myometrium (muscle layer). Studies have looked at uterine junctional zone dysfunction in adenomyosis and how this affects fertility outcomes. In one study it was found that implantation failure was higher in those who had a thicker uterine junctional zone (greater than 7mm), leading to a reduced overall implantation rate. There are medical treatments that can change the lining of your uterus, to make it either thinner or thicker.
Miscarriage
In another study, it was found that miscarriage rates were higher in women who had diffuse adenomyosis (versus focal adenomyosis) giving them a more enlarged uterus. Another study looked at the miscarriage rate between groups of women who had adenomyosis alone, versus those with adenomyosis and endometriosis and found that miscarriage was significantly higher in the adenomyosis group.
2. Anatomical and chemical differences
A theory is that adenomyomas may contribute to impacted fertility. An adenomyoma is a nodule or focal region of adenomyosis that results in a mass. This can often be difficult to differentiate from fibroids. Adenomyoma may obstruct the transit of the embryo through the fallopian tube and interfere with movement of sperm.
Research found that estradiol levels were higher in the menstrual blood of women with adenomyosis. This suggesting that there is an increased estrogen production and concentration of estrogen in the uterus of women with adenomyosis, leading to an imbalance of estrogen vs. progesterone. There is overall altered estrogen and progesterone receptor function in those with adenomyosis (lots of confusing science-y lingo!).
High levels of estrogen and low levels of progesterone can be improved with medical management. This includes hormonal treatments like the Mirena, oral contraceptive or administration of GnRH (gonadotropin-releasing hormone agonist / antagonist). It is essential you receive appropriate treatment from your healthcare team prior to trying to conceive, as prior treatment may impact successful pregnancy rates.
Adenomyosis often occurs with other uterine disorders. One hospital stated that more than 80% of their population of women with adenomyosis, also have another condition of the uterus. This includes fibroids, endometriosis and endometrial polyps (both polyps and fibroids being generally benign uterine masses). The symptoms of each of these conditions can make diagnosis of adenomyosis more difficult as pain, infertility and impacted reproductive outcomes can be associated with anyone (or all) of these.
3. Abnormal inflammatory response
Adenomyosis is a chronic inflammatory condition. As part of the inflammatory response, increased proinflammatory markers are produced in women with adenomyosis. This includes ROS (reactive oxygen species) that can damage embryos, and an abnormal inflammatory response, which can impact fertility. This leads to increased levels of inflammation in the uterine cavity, potentially affecting egg quality, and contributing to a less than ideal uterine environment.
Inflammation caused by adenomyosis, can be reduced and assisted by following anti-inflammatory diet principles, and by working with a fertility dietitian. By consuming an antioxidant rich diet, you can improve egg quality, and uterine environment, to improve chances of implantation. The boys can also work on improving their sperm quality to really create that high quality embryo. You can read more about diet and adenomyosis.
Impact of Adenomyosis on pregnancy
Some studies have shown that adenomyosis has a negative impact pregnancy outcomes, however less of an impact on actually falling pregnant. Adenomyosis can lead to less successful IVF outcomes, as well as an increased risk of miscarriage, and premature birth.
The research points to the main issues of fertility for those with adenomyosis as being a decreased ability to carry a pregnancy to term. It may take longer than the average person to conceive, and there is an increased likelihood that women with adenomyosis will need to access assisted reproductive technology.
Again, this is also only a proposed theory and not necessarily echoed by all health professionals, or the current research.
Unfortunately for adenomyosis sufferers, there are no universally decided or known risk factors for developing adenomyosis, and to what extent the impact of adenomyosis has on pregnancy and fertility. The research still provides a mixed picture, and idea of exactly HOW adenomyosis affects fertility, and birth rate.
Conclusion:
A major take home message for this blog to be aware of your options. The research is somewhat promising in that receiving treatment for adenomyosis prior to conception, can improve your fertility and chance of a ‘textbook’ healthy pregnancy. Treatments can include medical therapies, hormonal treatment, conservative treatment and non-medical treatments. Read here for more on this.
Having adenomyosis does not automatically mean that you will have trouble falling pregnant, or experience any of the above. Accessing the most effective, safe, and minimally invasive strategies to manage adenomyosis can help with improving pregnancy rates, IVF outcomes, and achieving a full-term pregnancy. An important lesson from this is to make sure that you are aware of your treatment options, and to seek advice about your fertility prior to conception, whether it from a doctor or a women’s health dietitian.
If you want assistance with managing your adenomyosis or endometriosis, or chances of conception with these conditions, book a consultation today!
