Cervical Mucus - the Biochemical and Molecular Properties in Fertile and Subfertile Women (C-MIS Study)

Infertility affects approximately one in six couples1. In approximately one third of cases, there is no cause found as to why a couple are unable to conceive2. In order for natural pregnancy to occur, sperm must pass through the cervix (neck of the womb) and swim to the woman's Fallopian tubes so that fertilisation of one of the woman's eggs can occur. It is known that mid-cycle mucus at the cervix is essential for sperm to gain access to the uterus and tubes.

There is evidence that the composition of this mucus in women may affect fertility but this area has not been studied well in recent years, partly because fertility treatments such as IVF bypass the cervix.

Research in sheep and cows in UCD has shown interesting differences in the cervical mucus of fertile and infertile animals. It appears that the mucus not only helps sperm to get to the uterus but may also help the sperm to mature and be ready to fertilise an egg. This mucus may also help prevent bacteria and infection reaching the womb.

In conjunction with colleagues in UCD, under the leadership of Professor S Carrington, the investigators would like to investigate some of the properties of human cervical mucus.The investigators propose to do this by taking samples of cervical mucus around the time of ovulation and also approximately one week later in fertile women and sub-fertile women. Then to monitor ovulation with an ultrasound scan (follicle tracking) of the woman's ovaries and urinary ovulation kits and take blood for oestrogen, progesterone, LH and FSH levels.

The investigators wish to determine if there are differences between the mucus of these women and how it may impact on sperm function and on fertility.