Tackling Fertility in Endometriosis

Endometriosis Awareness Month

What is endometriosis?

Endometriosis is a chronic inflammatory condition that affects up to 1 in 10 women of reproductive age, and typically causes pelvic pain, painful periods and reduced fertility. In clinical terms, endometriosis means the growth of endometrial tissue (i.e. internal lining of the uterus or womb) outside the uterus. This can occur anywhere in the pelvis, most commonly behind the uterus, on the ovaries or in front of the uterus, and very rarely in regions distant from the pelvis, such as the lungs. Just like the endometrial lining of the uterus, these endometriosis lesions also release blood and inflammatory factors into the pelvis during menstruation. Over time, this can cause scarring, cysts and adhesions in some women, increasing pain around periods and even throughout the menstrual cycle. The presence of endometriosis can only be confirmed by laparoscopic (keyhole) surgery. Depending on the amount, location and type of endometriosis lesions observed by the clinician during laparoscopy, the disease is graded as minimal (Stage I), mild (stage II), moderate (stage III) and severe (Stage IV).


What causes endometriosis?

Despite being recognized since the 1800s, its high prevalence in the global female population and the significant economic and medical impacts it imposes, the exact cause of endometriosis remains poorly understood. The leading theory is that of ‘retrograde menstruation’, i.e. that during menstruation, blood can reflux back through the Fallopian tubes and into the pelvis, carrying small fragments of endometrial lining. It is thought that these fragments can either implant and themselves cause endometriosis, or stimulate the lining of the pelvis to develop into endometriosis. In support of a role for retrograde menstrual bleeding, it is very unusual for endometriosis to occur in women who are not menstruating, and it is more common in women who have long, heavy and frequent periods. However, retrograde menstruation is estimated to occur in up to 90% of women, while only 10% of women will develop endometriosis, so this is clearly not the whole story. We know that there is a genetic predisposition for endometriosis, particularly the severe forms of the disease. Women who have a first-degree relative (i.e. mother or sister) with endometriosis are six times more likely to develop it themselves, but as yet there is no genetic test to determine endometriosis risk. No major differences have been found in the actual menstrual blood of women with or without endometriosis, but a number of studies have shown distinct changes in the endometrial lining of the uterus itself. Differences have also been found in the pelvic fluid of women with endometriosis, but whether these changes are a cause or result of the disease remains unknown.


How does endometriosis affect fertility?

Endometriosis is a leading cause of reduced fertility in women, occurring in  30-50% of women attending fertility clinics for assisted reproduction. However, up to two-thirds of women with endometriosis will have no difficulty conceiving, and it is not yet clear what distinguishes those women who will struggle from those who will not. In severe endometriosis, distortion of the ovaries and Fallopian tubes can impede fertilization and pregnancy establishment, while ovarian cysts (called endometriomas or chocolate cysts) can interfere with ovulation and the ability of the ovary to produce good quality eggs. In milder grades of endometriosis, where the pelvis is not significantly distorted, the reasons for subfertility are less obvious. Many studies have indicated that the immune system of women with endometriosis-associated infertility may be different to that of healthy fertile women. For instance, studies have revealed increased inflammatory factors in the fluid of the peritoneal cavity and in the endometrium of women with endometriosis, which are likely to impact ovulation, egg development and embryo implantation. Research from Merrion Fertility Clinic, in collaboration with Trinity College Dublin, found differences in uterine immune cells in women with endometriosis-associated infertility who had a successful cycle of IVF compared to women who were unsuccessful. While there is compelling research evidence of immune dysfunction, it is important to note that, as yet, there are no  immune tests or treatments that are of value. Neither is there any international consensus on the cause or mechanism of subfertility in endometriosis.


What are the options to treat infertility in endometriosis?

For women with endometriosis who are trying to conceive, it is generally recommended that they seek help after 6 months of trying. If a woman is unsuccessful after a year of trying, it is very likely that she will need assistance to conceive. The two main options are surgery or assisted reproduction, most commonly IVF. For women with mild forms of endometriosis, there is evidence that surgical removal or destruction of the lesions can improve fertility, possibly by reducing pelvic inflammation. Surgery has also been shown to improve fertility in severe endometriosis. If the pelvis is restored to a near normal state, around 30-50% of women will conceive in the 12 months following surgery. For this reason, for young women with no other significant infertility factors (e.g. partner’s sperm quality), laparoscopic surgery is typically the first option. In women over 35, the benefits of surgery as opposed to proceeding directly to assisted reproduction need to be carefully weighed. IUI is a viable option only for women with mild disease (Stages I and II), but not for those with significant scarring or inflammation. IVF is a very effective treatment for the majority of women with endometriosis. For young women with severe endometriosis, who are not yet in a position to conceive and may require major surgery and/or removal of an ovary, egg freezing (oocyte vitrification) should be considered as an option to preserve their future fertility.



For further reading, please see:

The Fertility Handbook (Gill Press), Professor Mary Wingfield




Is Fertility Law in Ireland set to change?

Fertility Law

Legislation regarding assisted reproduction in Ireland has yet to be implemented, and while we await formation of our new government, it is not clear when this will proceed. Parts of the Children and Family Relationships Act 2015 (CFRA) that deal specifically with donor-assisted human reproduction (excluding surrogacy) are due to take effect on 4 May 2020. This will leave a number of important issues unresolved, including parentage of children born to LGBT families using donor assisted technologies, the legal position of their parents, and the status of donor gametes currently in storage.

Solicitor Fiona Duffy, partner at Patrick F O’Reilly & Co., discusses the current legislative and regulatory concerns surrounding ART in Ireland in the article below:


First baby born from In Vitro Matured (IVM) frozen eggs

Frozen EggsThe world’s first successful pregnancy resulting from immature eggs that were matured in the lab before being frozen has been reported. This is an important breakthrough for fertility preservation in cancer, where patients may not have time to undergo traditional egg freezing before starting chemotherapy.   To read more click on the link below:



Pre-Implantation Genetic Testing

Pre-Implantation Genetic Testing:


PGD (Pre-implantation genetic diagnosis) was developed several years ago and is an excellent technique for diagnosing embryos that have a specific genetic disease such as cystic fibrosis or muscular dystrophy.  This helps people who have a strong family history of such conditions to consider only using embryos that are not affected by these conditions.

PGS (Pre-implantation genetic screening) on the other hand is a similar technique applied to embryos  in the hope of identifying changes in the numbers of chromosomes in the embryo.    Embryos with a normal pattern of chromosomes (euploid) have the best chance of developing into a healthy baby, whereas aneuploid  embryos, that do not have the correct number of chromosomes, are less likely to implant and, if they do, the pregnancy is more likely to end in miscarriage or the birth of a baby with a genetic condition.

In recent times, more and more clinics are offering PGS for couples undergoing fertility treatment.     The exact place of PGS has yet to be determined as there are still many questions to be answered about the technique.    While it can reduce the number of miscarriages and failed pregnancies, it has not yet been shown to increase the number of live births from an IVF or ICSI treatment.    There are no studies on the long term effects of this technique as it has just not been around long enough.     In addition, the results are not always straight forward.   A significant problem is mosaicism, where some cells have a normal number of chromosomes and others don’t.  In these cases, it can be difficult for geneticists to determine the likely outcome of such pregnancies.  There have also been cases of false positive and false negative test results.

For all these reasons, Merrion Fertility Clinic’s policy at present is to recommend PGS for certain of our patients but not for all couples undergoing IVF.   However, we are cognisant that this is an evolving issue and that, as more studies are done, hopefully, the true role of PGS and its place in fertility treatment will be established.

Recently the HFEA, the official regulatory body for Assisted Reproduction in the UK,  determined that PGS should be classified as a ‘red status IVF treatment add on’ i.e. that ‘there is no evidence that the treatment is effective and safe’.  This decision is controversial.  It certainly has merit but others in the field disagree.    For that reason Merrion Fertility Clinic, as described above, takes an individualised approach to patients when discussing the benefits and risks of PGS.


For more reading:



Merrion Fertility Clinic’s Top Ten Highlights of the Past Decade

No. 1: Expanded Facility

2010: We moved into our current facility in no.60 Lower Mount Street which gave us the space we needed to grow and expand our services, while still being part of the National Maternity Hospital complex. We also had a state-of-the-art laboratory built.

No. 2: Donor Egg Service Launched

April 2015: We announced that we had established a satellite service to support appropriate patients requiring donor egg treatments. Our satellite service comprises pre-pregnancy medical advice and counselling, psychological support, arrangement of pre-requisite tests and prescriptions, provision of necessary ultrasound scans and tests during treatment, and relay of results to overseas clinic.   READ MORE



No. 3 Launch of MFC Support Group

August 2015: We began our support group which runs every month and is facilitated by our very experienced fertility counsellor, Kay Duff. This allows our patients to share their feelings and stories. The fertility journey can be emotionally demanding and many couples and individuals have benefited from the support of this group.   READ MORE



No. 4 Awarded Guaranteed Irish Membership

June 2017: We are a not-for-profit, Irish clinic. Not all fertility clinics are Irish-owned; some are owned by foreign corporations, which are answerable to shareholders. Our partnership with Guaranteed Irish reflects our MFC values of quality in patient services and care, and our commitment through education, research and training. As Ireland’s only fertility clinic with ‘Guaranteed Irish’ membership, we take great pride in reflecting the Guaranteed Irish beliefs of Provenance, Quality and Trust.   READ MORE



No. 5 Prof Mary Wingfield Launches ‘The Fertility Handbook’

June 2017: This comprehensive, research-based book provides excellent guidance on the fertility journey. Proceeds go to the Merrion Fertility Foundation, our sister charity which provides financial support to those who cannot afford fertility treatment.   READ MORE






No. 6 Prestigious Grant for Fertility Innovation Received

July 2018: We received the highly competitive grant for fertility innovation for our research on the role of endometrium (lining of the womb) in embryo implantation at the 34th annual meeting of the European Society of Human Reproduction and Embryology (ESHRE). Dr. Louise Glover, Research and Development Coordinator at MFC, was awarded the Merck GFI (Grant for Fertility Innovation) for this project. Dr. Glover is pictured below with Louise Brown, the first child born through IVF at the award ceremony.   READ MORE





No. 7 Certified as Complying with ISO 9001:2015 

November 2018: We are regularly audited by the Health Products Regulatory Authority (HPRA) to ensure compliance with the highest standards in relation to the Tissues and Cells legislation. We decided to transition to ISO 9001:2015 from the 2008 version of the quality management standard, which ensures that all processes are governed by Standard Operating Procedures and that any non-conformances result in corrective action so that our system is continuously improving.


No. 8 First Baby Born from Frozen Eggs

December 2018: We were delighted to announce the arrival of our first baby born through our egg freezing program. Egg freezing or ‘oocyte vitrification’ was first introduced in MFC in September 2016, so this successful pregnancy and birth within only 26 months of establishing the service was a testament to the expertise, hard work and outstanding dedication of the MFC team.




No. 9 First Baby Born through the Donor Sperm Program

December 2018: We were delighted to welcome our first baby conceived using the donor sperm service at our clinic. This successful pregnancy and birth occurred less than one year after introduction of the donor sperm program in MFC in 2017.   READ MORE



No. 10 MFC Patients

We are delighted to have been able to help thousands of patients achieve their dreams over the last decade.  We help patients through our various services, some of which are Ovulation Induction, IUI, IVF, ICSI, Egg Freezing, Donor Sperm Services and SSR.  One of our patients shared the following story on her IVF journey:    READ MORE



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Also, if you ever wish to consider fertility treatment, you can self-refer to our clinic by clicking here.

MFC Research at Fertility 2020

Fertility Research


Research and clinical staff from Merrion Fertility Clinic presented their findings recently at the Fertility 2020 Conference in Edinburgh. Clinical Fellow, Dr Lucia Hartigan, described her work on fertility preservation practices and referral pathways for children and adolescents with cancer in Ireland.

Doctors Fiona Reidy and Maebh Horan described the clinic’s ongoing collaborative project with Trinity College Dublin on the role of endometrial inflammation in early pregnancy.

Fertility 2020

Fertility 2020

The 2020 Joint Conference of the Association of Clinical Embryologists, British Fertility Society and the Society for Reproduction & Fertility is currently being held in Edinburgh.  The theme for the joint annual conference is ‘Reproduction in a changing world. 

MFC is well represented at the conference with staff from our clinical, nursing, embryology and research departments.  For more information on the conference please click on the link:



Fertility 2020

Christmas Opening Hours

The clinic will be closed from 4pm on Monday, 23rd December and will re-open at 8am on Thursday, 2nd January.

If you are an existing patient and have a serious concern please contact The National Maternity Hospital on 01 6373100.  Otherwise, you may leave a voicemail message on tel. no.  01 6635000 and this will be dealt with by one of our nurses on Monday, 30th and Tuesday, 31st December.

Christmas Opening Hours

Feminism, Fertility and Reproduction

Irish Research Council


Professor Mary Wingfield will speak about Fertility and the Future at the Feminism, Fertility and Reproduction conference being held by the Irish Research Council at NUI Galway today, 4th December.