Falling Pregnant With Endometriosis: What You Need To Know

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What are the chances of getting pregnant with endometriosis?

Falling pregnant with endometriosis is certainly possible, but it can be very difficult for various reasons.

One study reports that endometriosis affects between 10–15% of the general population. The number of people who experience infertility and are diagnosed with endometriosis is as high as 25–50%.¹

These are staggering statistics, so it is no wonder infertility is such a significant cause of stress amongst people with endometriosis.

Staging of your endometriosis and the effect on fertility

According to the American Society of Reproductive Medicine (ASRM), there are four stages of endometriosis.² They are assigned based on a score derived from the number of lesions, severity, depth, and involvement of other organs.

This method quantifies the disease but doesn’t necessarily match up with the severity of symptoms or chances of pregnancy. So, some clinicians and organizations like EndoFound use a system that better describes the likely outcomes for the individual woman.

This system discusses three main subtypes of endometriosis, increasing in severity from superficial peritoneal lesions (SUP) to ovarian endometrioma (OMA) and finally to deep infiltrative endometriosis (DIE1 and DIE2).³

Surprisingly, the most severe form of endometriosis (DIE) does not represent the greatest threat to fertility. Studies have shown that the most minimal form (SUP) is linked to the highest infertility rates.⁴ However, having endometriosis does not categorically mean you will also have infertility.

Researchers developed a tool called the endometriosis fertility index (EFI), which accurately assess a woman’s likelihood of conceiving after laparoscopic surgery if she has stage III or stage IV endometriosis.⁵

The EFI is a clinical tool that doctors can use when counseling their patients about the best approach when trying to conceive. Their expected rate of success depends on their classification.

Why falling pregnant with endometriosis is so difficult

Researchers have discovered several reasons why women with endometriosis can find it hard to fall pregnant, and it is far from a simple problem.

These include physical differences in anatomy, biological reasons, egg quality and amount, sexual issues, and hormonal/ovulatory problems.

Anatomical causes

The inflammation associated with endometrial deposits on organs in the pelvic cavity can cause scar tissue called adhesions.

These often connect and fuse different organs together, usually in the wrong positions. The organs cannot move freely, and so their function is inhibited.

Adhesions can also cause the fallopian tubes to “stick” together, which prevents the egg and sperm from being able to meet and fertilize successfully.

Biological causes

Endometriosis is an inflammatory condition closely associated with the immune system and its inflammatory cells. The release of these types of cells and their associated inflammatory signals can lead to an inhospitable environment for sperm and eggs to exist in, for fertilization to be successful in, and one where it’s difficult for an embryo to implant.

Ovarian function

The egg quality in women with endometriosis is often negatively affected for a few reasons.

Firstly, if they have ovarian endometriomas (OMAs) or “chocolate cysts,” they can affect ovarian function itself. However, surgery for these cysts can reduce ovarian reserves later on.

Secondly, endometriosis can disrupt essential hormone levels, and these changes then alter the menstrual cycle phases and subsequent development and release of eggs. These functions rely on optimum hormone levels and correct timing, and when this isn’t the case, an egg may not be released with your cycle.

And thirdly, there is a condition called luteinized unruptured follicle syndrome (LUF), where the follicles containing the eggs develop nicely and become dominant. Still, they never actually rupture and release their egg, making conception impossible.

Dyspareunia or painful sex

The adhesions from endometriosis, their effect on nerves, and the inability of organs to move freely cause pain during sex (dyspareunia).

It can be an issue when it comes to fertility because the pain often causes sex to become infrequent, reducing the chances of conception.

The cruel irony is that most effective treatments for pelvic pain also act as contraception, like oral contraceptives, which will, of course, prevent conception anyway.

How to get pregnant naturally with endometriosis

Natural conception with endometriosis is certainly possible. However, studies have consistently shown that successful pregnancy rates are lower than normal.

It is also important to note that most medical treatments for endometriosis hamper ovarian function. It is why they are effective in treating symptoms and why they act as contraceptives.

It also seems that fertility does not increase after stopping the treatments, so you should carefully consider the timing of when you want to start your family.

Surgery to identify and remove endometriosis deposits is one of the few non-contraceptive methods available to treat the condition. It also improves your chances of falling pregnant.

Following surgical treatment of endometriosis lesions, a study of 222 women showed that at 18 months post-surgery, approximately 30% had conceived. At 36 months post-surgery, about 50% had conceived.⁶

Due to the decreased likelihood of natural conception with endometriosis, you may want to consider an assisted reproductive technique (ART) earlier than someone who doesn’t have the condition.

Women who don’t have endometriosis are advised to try natural conception for a year before speaking to a specialist. But if you have endometriosis, it is recommended that you seek assistance after six months.

Unfortunately, when it comes to conceiving, time is the enemy. If you know your chances are already likely to be reduced, it’s recommended to ask for help earlier.

Not only can it increase your chances of having a baby, but you can also gain empathetic, specialist support at what is usually a very difficult time.

Intrauterine insemination (IUI)

IUI is where lab-prepared spermatozoa (found in semen) are introduced straight into the uterus during ovulation, saving the sperm from finding its way into the correct location.

IUI can be used in patients with mild endometriosis where their partner has a normal sperm count.

The studies currently available on this method are not conclusive. However, one Dutch study with a large cohort of participants found a good outcome for these couples when combining IUI with follicle stimulation.⁷

In-vitro fertilization (IVF)

IVF is where an egg (oocyte) is fertilized with spermatozoa in a laboratory setting before being introduced to the womb.

This process starts with egg development stimulated by drugs. The eggs are then harvested during an egg retrieval procedure, performed as a day operation.

Once collected, the eggs are fertilized in a lab setting and monitored for three to five days for signs of successful maturation. The best embryo is transferred back into the mother’s uterus.

Studies show that the milder the endometriosis is, the better the chance of a live birth following IVF.4IVF is just as effective in treating endometriosis-related infertility as that caused by other conditions.

There are also some downsides to considering IVF: it is invasive, very restrictive, can result in many side effects depending on the required treatments, and is costly.

Surrogacy/adoption

Some people choose to pursue options that remove the complexity of having endometriosis when trying to conceive. It may be after IVF has failed or if that process’s emotional and financial investment is too great.

In these cases, there are options like surrogacy or adoption. They are often fraught with their hurdles. However, they may provide the assurance you need of being able to start a family.

Complications of endometriosis if you do conceive

Typically, the symptoms of endometriosis improve during pregnancy because ovulation and menstruation are paused.⁸ This means there is no bleeding and no associated inflammation of the endometrial tissue outside the uterus.

This is encouraging and means if you have endometriosis, you are likely to be in for a few months or years of reprieve from your symptoms if you fall pregnant.

Complications for the mother

Though very rare, there are potential complications of endometriosis that may impact you during pregnancy.

Bowel perforation

If you are pregnant and have endometriosis, you are at a greater risk of bowel perforation. In this medical emergency, the bowel wall develops a tear or hole.

It is thought to occur because of the increase in abdominal pressure during pregnancy, the traction of the enlarged uterus against the colon, and adhesions from previous DIE-related surgeries.⁹

Although this is relatively rare and sounds drastic, it’s perfectly treatable when your doctor detects it early.

One study found that despite surgical treatment for bowel perforation in pregnancy, all pregnancies still resulted in live births. Only 37.5% of them were preterm.¹⁰

Uterine rupture

Surgical treatment of endometriosis creates scar tissue, altering the movement and stretch of the womb’s muscle.

The wall of the womb can also be affected by a condition called adenomyosis, which is present in up to 90% of women with endometriosis.¹¹

Changes to the muscle of the womb cause rupture of the uterine wall before and during labor.

One study reported an odds ratio of 2.7 in pregnant women with endometriosis.¹² This means that you’re 2.7 times more likely to have a uterine rupture if you have endometriosis and are pregnant.

Uroperitoneum and hemoperitoneum

Like bowel perforations, other structures can be affected during pregnancy by scarring related to endometriosis.

When this causes injury to the bladder or ureters, urine is released into the abdominal cavity called the uroperitoneum. When it affects blood vessels or organs with high blood flow volumes, blood is released into the abdominal cavity, called hemoperitoneum.

These are relatively rare occurrences, but they cause acute pain and put the mother at increased risk of infection. Due to the severity of these situations, they almost always result in surgery to treat the problem. In most cases, the baby still survives.

Miscarriage

Endometriosis has been found to result in a higher chance of miscarriage across all types of the disease (minimal, mild, and severe), with the minimal form (SUP) being the most strongly associated, followed by the mild form (OMA), with the severe form (DIE) having the least prevalence of miscarriage.¹³

Pre-eclampsia

Hypertensive disorders such as pre-eclampsia and their association with endometriosis are still debated. Some studies show an increased risk of pre-eclampsia.

On the other hand, others found a significantly lower prevalence of pre-eclampsia in pregnant patients with endometriosis, further fuelling the debate.¹⁴

Placenta previa

Placenta previa is where the placenta incorrectly attaches to the lower portion of the uterus, causing it to partially or completely cover the cervix (neck of the uterus).

This can result in bleeding throughout pregnancy. Because it blocks the normal passage for a baby’s birth, it will require you to have a cesarean section.

This condition is consistently higher in those with endometriosis than in the general population.¹⁵

Preterm birth

The risk of preterm birth also increases if you have endometriosis.¹⁶ This results from the local inflammation in endometriosis, causing an imbalance between the placenta’s decidua and trophoblasts (maternal and fetal cells, respectively). A suboptimal interface forms between the baby and mother during implantation, resulting in preterm birth in some cases.

Small for gestational age (SGA) babies

SGA babies are described as weighing less than the 10th centile compared to the birthweight of other babies born at the same gestation.

A range of studies has found women who have endometriosis were more likely to deliver an SGA baby than women in the control groups.

Cesarean delivery

Although there are limited studies, researchers generally found that cesarean delivery is more common in women with endometriosis than in general. The cesareans in this group are most common in the pre-labor phase.

A retrospective study in 2012 found that 65.4% of women with endometriosis delivered vaginally, while the remaining 34.6% delivered either by emergency or elective cesarean. The leading causes for these surgeries were fetal distress (24%), breech positioning, and slowly-progressing labor (both 13%).¹⁷

Given that cesarean delivery often occurs due to maternal complications or fragility of the baby, it is both unfortunate and unsurprising that the chances of it happening are higher if you have endometriosis.

The lowdown

Endometriosis is a difficult and painful inflammatory condition to have, which can cause a lot of angst when trying to conceive.

However, there are options to assist with conception, and in fact, natural conception is still possible.

The most important thing is to be kind to yourself or those in similar situations and seek help from a specialist.

  1. Endometriosis and Infertility: A review of the pathogenesis and treatment of endometriosis-associated infertility (2012)

  2. Classification of endometriosis (2021)

  3. Endometriosis stages: Understanding the different stages of endometrios | EndoFound

  4. Endometriosis-associated infertility: aspects of pathophysiological mechanisms and treatment options (2016)

  5. Endometriosis fertility index predicts live births following surgical resection of moderate and severe endometriosis (2017)

  6. Endometriosis and infertility: pathophysiology and management (2010)

  7. Prediction of an ongoing pregnancy after intrauterine insemination (2004)

  8. A systematic review on endometriosis during pregnancy: diagnosis, misdiagnosis, complications and outcomes (2016)

  9. Deep endometriosis induced spontaneous colon rectal perforation in pregnancy: Laparoscopy is advanced tool to confirm diagnosis (2014)

  10. Obstetrical complications of endometriosis, particularly deep endometriosis (2017)

  11. Adenomyosis in endometriosis--prevalence and impact on fertility. Evidence from magnetic resonance imaging (2005)

  12. Maternal–fetal outcomes in women with endometriosis and shared pathogenic mechanisms (2021)

  13. Endometriosis, especially mild disease: a risk factor for miscarriages (2017)

  14. Endometriosis and risk of adverse pregnancy outcomes (2019)

  15. Placenta previa complicated with endometriosis: Contemporary clinical management, molecular mechanisms, and future research opportunities (2021)

  16. Endometriosis and adenomyosis are associated with increased risk of preterm delivery and a small-for-gestational-age child: a systematic review and meta-analysis (2018)

  17. Pregnancy outcome in women with peritoneal, ovarian and rectovaginal endometriosis: a retrospective cohort study (2012)

Have you considered clinical trials for Endometriosis?

We make it easy for you to participate in a clinical trial for Endometriosis, and get access to the latest treatments not yet widely available - and be a part of finding a cure.

Joining community groups and exercise programs for my condition made me feel empowered – but I want to be part of finding a cure.
Peter, 64


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