Adenomyosis interferes with fertility at multiple levels, from disrupting sperm transport to impairing the uterine lining’s ability to support an embryo. Women with adenomyosis are roughly three times more likely to be diagnosed with recurrent miscarriage compared to those without it (19.7% vs. 6.1% in one study). The good news: adenomyosis does not appear to damage egg quality, and several treatments can significantly improve the odds of a successful pregnancy.
How Adenomyosis Disrupts Uterine Contractions
The uterus contracts in rhythmic waves throughout the menstrual cycle, and these contractions serve a purpose well before pregnancy. In the days leading up to ovulation, the uterus increases contractions that move upward toward the fallopian tubes, essentially helping guide sperm to where they need to go. Adenomyosis disrupts this system in measurable ways.
A meta-analysis of uterine contractility found that women with adenomyosis have significantly fewer contractions overall and far fewer of these upward (antegrade) contractions compared to women without the condition. Instead, the contraction pattern becomes random and disorganized, with a higher proportion of downward movements that work against sperm transport. This happens because adenomyosis physically alters the architecture of the junctional zone, the inner muscle layer of the uterus that generates these waves. When tissue from the uterine lining grows into this muscle layer, the normal contraction machinery breaks down.
Why Embryos Struggle to Implant
Even when fertilization succeeds, adenomyosis creates a hostile environment for implantation. The uterine lining goes through a tightly orchestrated process each month to become “receptive,” meaning ready to accept an embryo. This window of receptivity depends on specific molecular signals, and adenomyosis suppresses several of the most important ones.
Research comparing endometrial tissue from women with and without adenomyosis has identified clear deficits during the secretory phase, the critical window when implantation would occur. Progesterone receptors in the uterine stroma are significantly reduced, which matters because progesterone is the hormone responsible for preparing the lining to nurture an embryo. Leukemia inhibitory factor (LIF), a signaling protein essential for embryo attachment, is also significantly lower in adenomyotic tissue during this phase.
Perhaps most striking is what happens to HOXA10, a gene that acts as a master regulator of uterine receptivity. In healthy tissue, HOXA10 expression is strong in both the proliferative and secretory phases. In women with adenomyosis, it remains low throughout the entire cycle in the stromal compartment. Osteopontin, another molecule involved in embryo adhesion, follows the same pattern of suppression. The cumulative effect is a uterine lining that looks normal on imaging but is molecularly unprepared for pregnancy.
Inflammation and Structural Damage
Adenomyosis also triggers extensive inflammatory responses within the uterine wall. Histological studies show architectural disruption of the muscle layers alongside increased local inflammation. At the molecular level, this involves overactivation of inflammatory signaling pathways, including those related to tumor necrosis factor, a potent inflammatory molecule. These inflammatory signals further degrade the uterine environment and can interfere with early embryo development.
Animal research has demonstrated that adenomyosis doesn’t just reduce the chance of implantation. It also disrupts the spatial organization of embryos that do implant, causing irregular distribution with reduced distances between implantation sites. This compromised spacing can affect how well each embryo develops and may partly explain the higher miscarriage rates seen in women with the condition.
Egg Quality Is Not the Problem
One reassuring finding: adenomyosis does not appear to affect the eggs themselves. A large study evaluating over 205,000 oocytes found that adenomyosis had no impact on oocyte morphology. This is an important distinction because it means the fertility challenges are primarily uterine, not ovarian. Your ovarian reserve and egg quality remain intact, which has direct implications for treatment options.
How Location and Severity Change the Prognosis
Not all adenomyosis carries the same fertility impact. Where the disease sits within the uterine wall matters considerably. A retrospective analysis of oocyte donation cycles found that when adenomyosis was limited to just the junctional zone, cumulative live birth rates reached 83.3%. When it was confined to the outer muscle layer alone, rates were 78.6%. But when adenomyosis involved both the outer muscle layer and the junctional zone, live birth rates dropped to 62.5%, and these women required more embryo transfers to achieve pregnancy. Multivariate analysis confirmed that this combined pattern independently predicted lower chances of a live birth.
Ultrasound diagnosis has become more standardized thanks to the MUSA guidelines, updated in 2022, which define specific direct and indirect markers of adenomyosis. Among these features, subendometrial lines and buds showed the highest diagnostic accuracy. Getting a detailed ultrasound assessment that characterizes the location and extent of disease can help predict how much adenomyosis is likely to affect your fertility and guide treatment decisions.
Hormonal Pretreatment Before IVF
For women pursuing IVF, suppressing adenomyosis with hormonal therapy before embryo transfer can meaningfully improve outcomes. Long-term pretreatment with a GnRH agonist, a medication that temporarily shuts down estrogen production and shrinks adenomyotic tissue, has been shown to increase both implantation and live birth rates while cutting miscarriage rates.
In one study, women who received this extended suppression before a frozen embryo transfer had roughly 70% higher odds of implantation and 69% higher odds of a live birth compared to those who had no pretreatment. Miscarriage risk dropped by about 80%. The protocol works by quieting the inflammatory environment, thinning the adenomyotic tissue, and allowing the uterine lining to reset before the transfer cycle.
Surgical Options for Fertility
For women with diffuse adenomyosis, surgical excision of adenomyotic tissue is another option. A long-term study of 137 women who underwent a technique called double-flap adenomyomectomy found that 41% achieved pregnancy after surgery. Of those pregnancies, more than half (56.5%) were conceived naturally without any assisted reproduction, while the rest used IVF or similar techniques. Pregnancy outcomes were comparable between natural and assisted conception after surgery.
One of the strongest predictors of success after surgery was how much the junctional zone thickness decreased. Women whose maximum junctional zone thickness dropped to 8.5 mm or below after surgery had a cumulative pregnancy rate of 70.1% over three years. Those whose junctional zone remained thicker than 8.5 mm had a rate of just 20.9%. This suggests that the degree of surgical reduction directly correlates with how well the uterus can support a pregnancy.
The Miscarriage Connection
Adenomyosis doesn’t only make it harder to get pregnant. It also increases the risk of losing a pregnancy. Women with recurrent miscarriage are significantly more likely to have adenomyosis on ultrasound compared to women without a history of pregnancy loss. The same mechanisms that impair implantation, reduced progesterone receptor expression, lower levels of adhesion molecules, inflammatory signaling, and disorganized embryo spacing, continue to threaten pregnancy viability in the early weeks. This is why pretreatment strategies that calm the uterine environment before conception can reduce miscarriage rates as well as improve initial conception rates.