During this National Fertility Awareness Week 2023, we're excited to shine a spotlight on some of the amazing research happening in the field of Fertility and PCD. Scientists and clinicians are working hard to uncover new discoveries that can make it easier for people to have the families they've always dreamed of.
The research cover a wide range of topics, from better ways to help couples struggling with infertility to understanding how our bodies work when it comes to making babies.
Below we have included some summaries of ongoing research in this area.
Want to get involved in Fertility and PCD research? Head on over to our Get Involved in Fertility Research page by clicking on the following link: Get Involved in Fertility Research page
Fertility among people with PCD: results from COVID-PCD
At the University of Bern, Switzerland, we study fertility among people with primary ciliary dyskinesia (PCD) using data from the international study, COVID-PCD.
What is COVID-PCD and why was it set up?
COVID-PCD is an international study including people with PCD of any age from anywhere in the world. It was set up in 2020 in close partnership between PCD patient representatives and researchers at the University of Bern, Switzerland. People with PCD register online through the study website (www.covid19pcd.ispm.ch) and then receive questionnaires via email asking about their PCD, daily symptoms, treatment, and lifestyle. The initial aim was to study COVID-19 among people with PCD. After the first years of the pandemic, there was a strong interest from study participants to cover other topics related to PCD. One such topic, which was suggested by a participant, was fertility. Therefore, we developed a questionnaire together with fertility specialists and patient representatives to study fertility in people with PCD. The questionnaire was sent out in July 2022.
What did we want to find out?
People with PCD can have problems having children. It is important that they are informed about these problems before trying to have children and that they receive information about family planning options if needed. We therefore wanted to know how many people with PCD had ever visited a doctor who specializes in fertility, and at which point in their life. We also wanted to know if they were satisfied with the information about fertility. We were also interested in how frequent fertility problems are among people with PCD, how many have tried fertility treatment and in how many of them it was successful.
What did we find out?
We sent the fertility questionnaire to 723 people in COVID-PCD, and 384 study participants completed it. 266 were adults, 16 adolescents, and 102 parents of children with PCD. Only half of the adult participants had visited a doctor who specializes in fertility with a median delay of 10 years since diagnosis (or age 18 for people diagnosed during childhood). Females had seen fertility doctors less often than males. Only 56% of participants were satisfied with information about fertility they received from their PCD care team. Among adults who have tried having children, 37% of females and 20% of males were successful without any fertility treatments, 52% used fertility treatments, and of those, two-thirds were able to have a child. Overall, 63% were able to have a child.
What does it mean?
People with PCD are inconsistently referred to fertility doctors. We recommend care from fertility doctors become standard in routine PCD care, and that PCD doctors should already inform about fertility either at diagnosis or latest when patients transition to the adult service. Further, we showed that not all people with PCD have fertility problems and that a large proportion have children with fertility treatments. However, further studies are needed to confirm these results.
You can find more information about the COVID-PCD study and more detailed results on our website: https://covid19pcd.ispm.ch/en/
Written by Dr Eva Pedersen and Leonie Schreck:
Eva Pedersen is a researcher at the Institute of Social and Preventive Medicine (ISPM), University of Bern, Switzerland with a PhD in epidemiology. She has expertise in paediatric respiratory epidemiology and conduct of clinical and epidemiological studies. Leonie Schreck is a PhD student at the ISPM .
In men with Primary Ciliary Dyskinesia (PCD), issues with fertility or difficulty in fathering children are quite common, though not all PCD patients face these problems. It's important to note that infertility in PCD doesn't necessarily mean complete sterility, and assisted reproductive techniques can help for those experiencing fertility issues. Our research is focused on unravelling the connection between PCD and male fertility, especially in relation to the genetic diagnosis.
Previously, it's been observed that different genetic mutations in various genes can lead to varying degrees of fertility problems in PCD. However, this relationship is not well understood. Our study is dedicated to exploring how different PCD-causing genes can impact male fertility outcomes. Little is known about how certain PCD mutations affect sperm development, although in many cases the sperm quality is reduced.
We've been investigating how gene variants influence the structure, movement, and quantity of sperm, and this research is ongoing, relying on the participation of adult male PCD patients. Understanding the consequences of different PCD gene variants on sperm development is crucial for predicting the fertility status of PCD patients in the future. To achieve this, we're collecting semen samples from men diagnosed with PCD and analysing aspects such as sperm count, movement, shape, and the presence of specific proteins.
Our preliminary findings have shown significant reductions in sperm counts and motility issues, depending on which gene is affected. Our aim in analysing semen is also to identify potential markers in seminal fluid that can predict sperm quality. Some genes may not be essential for sperm development but could play a critical role in sperm maturation and their journey through the male reproductive system.
Sperm first travels from the testes to the epididymis through a structure known as the efferent duct, which contains motile cilia. Our research has revealed that genetic mutations causing PCD can affect the formation and movement of sperm tails, as well as the motile cilia in the efferent duct. We've found that these cilia have unique characteristics when compared to other types of motile cilia, including different movement patterns generating a circulating force to keep the sperm moving. The efferent duct cilia are also longer that airway cilia with structural differences suggesting a different role than the mucus removal in the airways.
The exact role of these cilia in sperm maturation remains unclear, and men with mutations in genes specific to motile cilia experience varying degrees of fertility problems (genes that don't affect sperm development, such as DNAH5 and DNAH11). This highlights the importance of further research to understand the functions of these male-specific motile cilia in fertility.
Our research also involves analysing gene expression to identify the types of cells in the efferent duct and their potential roles in ciliary function. PCD mutations may reduce sperm counts by causing dysfunction in the efferent duct cilia, which has been observed in some men with mutations in genes specific to motile cilia.
In summary, our research aims to provide a comprehensive understanding of how genetic mutations in PCD genes affect male fertility, which will aid in predicting the chances of natural conception or the need for assisted reproductive techniques. Additionally, understanding the precise role of male-specific motile cilia may lead to the development of therapies to improve fertility rates in individuals with PCD.
Written by Dr Anu Sironen:
Dr Anu Sironen is a Senior Research Fellow in the Genetics & Genomic Medicine Department at University College London. More information on Anu's research is available on the UCL website.
Primary ciliary dyskinesia (PCD) is a group genetic disorders affecting the function of tiny hair-like structures called cilia leading to upper and lower airway disease. As motile cilia and sperm tails share a similar structure, PCD is closely associated with male infertility. Although cilia also line the fallopian tubes, the role of ciliary function in female reproduction is poorly understood, although it has been hypothesized that females with PCD may be affected by fertility problems. So far, there are only small studies addressing female and male fertility issues in PCD.
Johanna has been working in the field of motile ciliopathies since 2010, and her research is focused on associated fertility problems. In Professor Omran's laboratory at the University Hospital in Münster, several studies are being conducted to explore various aspects of infertility related to PCD. These studies investigate severe defects in sperm morphology and motor proteins in males, both of which can lead to male infertility.
In 2021, their group described problems with motile cilia in the male reproductive system leading to male infertility in PCD. This is because the cilia in a specific part of the male reproductive system, the efferent duct, do not function properly due to mutations in a common PCD gene called DNAH5. This means young sperm cells cannot be transported through the male reproductive tract, resulting in low sperm count in the ejaculate.
Interestingly, the research also found that the cilia in the fallopian tubes of females with PCD, which are similar to the cilia in the airways, can sometimes allow for pregnancy and the birth of healthy children, even when the airway cilia are immotile.
In Münster, an international registry for PCD is maintained, with over 2300 individuals with PCD included so far (www.pcdregistry.eu). This registry is used for clinical and research studies to better understand the relationship between different PCD gene mutations and fertility issues in both men and women.
This research is part of a broader effort to improve the diagnosis, counseling, and care of individuals with PCD, addressing both respiratory problems and infertility. By studying the connection between PCD gene variations and fertility, researchers aim to enhance our understanding of this complex condition and its impact on reproductive health.
Written by Dr Johanna Raidt:
Dr Johanna Raidt, MD is a Senior Physician and Clinical Scientist in the Department of General Peadiatrics and Peadiatric Pulmonology at the University Children's Hospital Münster. She works in Professor Omran's laboratory (Link to Prof Omran's Munster laboratory website) and says you are welcome to get in contact with questions about her research: [email protected]
Researchers from the University of Southampton and University Hospitals Southampton NHS Trust UK are investigating the impact of PCD on fertility in men and women. Whilst it is known that fertility can be impaired in people with PCD, limited research has been done in this area.
The team including Dr Newman, Dr Chopra, Claire Dossett, Liz Shepherd, Dr Bercusson, Dr Carroll, Dr Walker, Prof Lucas and Prof Cheong recently published a review in May 2023 that looked at all published research on fertility in men and women with PCD. The review summarises how PCD might affect fertility. Link to the study in the following link: Review of fertility published in 2023
It also highlights that whilst many studies reported lots of men and women with normal fertility, both men and women with PCD appear to be at increased risk of fertility problems. The review highlights many areas where more research is needed on this topic in order to better understand why PCD affects fertility and better counsel people with PCD about their fertility and treatment choices if needed. The review also highlights some important considerations for health care workers involved in working with people with PCD.
The group works with PCD representatives to ensure that their work is guided by and beneficial to people affected by PCD. The group is currently planning further research studies aiming to address some of the current gaps in knowledge about fertility in men and women with PCD, and is hoping to open recruitment for research participants soon.