Natural hormone relaxin offers hope to infertile couples

A new study from the University of Leicester is investigating whether a naturally produced hormone could provide the key to helping couples conceive.

It will for the first time allow researchers to see how important the hormone –relaxin- is for human pregnancy

As part of her doctoral studies, Abigail Thompson is exploring the role that the relaxin hormone has in achieving a successful pregnancy. If the study is successful it is hoped that use of this hormone may improve fertility rates and help infertile couples to conceive.

Details of the study were made public at a Festival of Postgraduate Research at the University of Leicester.

Abigail, a Human Reproductive Biologist in the Department of Infection, Immunity and Inflammation, said: “Achieving a successful pregnancy is becoming ever more difficult for an increasing number of couples, young and old, with one in six couples experiencing difficulties conceiving.

“Implantation of the embryo into the uterus 6 or 7 days after fertilisation is essential to achieve pregnancy and its failure is a major cause of sterility, presenting a social and economic burden worldwide. Assisted reproductive technologies which can help to reduce levels of infertility are used by 27,000 couples a year in Britain alone. Despite this, the success rates remain low and the costs of fertility treatments stay high.”

Funded by EMBIC, the European Network of Excellence on Embryo Implantation Control, the research project aims to improve these success rates by determining factors which affect the implantation process.

The Leicester study is exploring the role of the hormone relaxin which is expressed during the first trimester of pregnancy in women.

Abigail said: “The role of this hormone in human pregnancy is poorly understood, however, it is known that in pig and rat pregnancy it plays an important role in widening of the birth canal and softening of the cervix during the third trimester, preparing these animals for labour.

“It is hypothesised that this hormone in humans may be involved in the implantation process of pregnancy, through softening of the uterine tissue at the site of implantation, allowing the embryo to obtain nutrients from the mother and for the placenta to eventually form.

“My research will involve using a model system to localise the relaxin hormone at the point of attachment and implantation of the embryo into the uterus, and to study its affects at this point.

“This work will for the first time allow us to see how important this hormone is for human pregnancy and could be a step towards improving fertility rates and infertility treatments worldwide, helping infertile couples to conceive.”

EMBIC is a European Union network of excellence on embryo implantation control, concentrating the research potential of 19 leading European institutions and 2 private companies in 11 countries for an improved understanding of infertility and its causes.

The research is being presented to the public at the University of Leicester on June 29. The Festival of Postgraduate Research introduces employers and the public to the next generation of innovators and cutting-edge researchers, and gives postgraduate researchers the opportunity to explain the real world implications of their research to a wide ranging audience.

More information on the Festival of Postgraduate Research at: