Dr Arvind Vaid
Hostile cervical mucus is one of the many causes for female factor infertility, though it accounts for only 15-20 percent only. In a normal cycle, the cervix produces watery mucus just prior to ovulation. Normally, this mucus protects the woman’s reproductive tract from invasion of foreign particles.
However, at the time of ovulation, the mucus transforms into a “friendly” path through which sperm can travel safely. Also, under the influence of estrogen the thick and sticky mucus becomes clear and stringy.
Function of Cervical Mucus
The primary function of cervical mucus is to protect the sperm on their journey to Fallopian tubes and help to keep them safe from the naturally acidic environment of the vagina. It aids the sperm to reach safely to the egg, which causes fertilisation, thereby, making a woman pregnant. But, sometimes the cervical mucus does more harm than good and therefore, instead of protecting sperms during conceiving, it turns “hostile” or unfriendly. Also, sometimes antisperm antibodies are present in cervical mucus due to which the immune system mistakes sperm for a foreign invader and thus, it either blocks the sperm’s passage or damages the sperm so severely that they can no longer function.
Hostile cervical mucus can also cause secondary infertility, or the inability to conceive after previously successful pregnancies.
The aim of fertility treatment is to restore the quality of the mucus so it can:
* Facilitate sperm transport at appropriate times of the month
* Protect the sperm from the acidic vaginal environment
* Preserve the sperm in the cervical canal and release them in a steady stream over a period of time
* Filter out abnormal or unhealthy sperms
* Protect the sperm from white blood cells which may destroy them
* Provide nutrients to the sperm
* Prevent bacterial contamination of the uterus
There are several causes responsible for hostile cervical mucus. Some of the common causes include:
Poor Diet: This is one of the most common causes for hostile cervical mucus. For a woman it is important to have a balanced, nutrition rich diet and have enough water daily so as to keep hydrated. Also, if you eat a lot of dairy products you may find that your cervical mucus becomes very thick
Medications: Another reason for hostile cervical mucus can be some specific group of medications. For instance, Antihistamines are said to be responsible for creating hostile cervical mucus in many women.
The postcoital test is the primary tool to access sperm-mucus interaction. It’s the test to diagnose cervical mucus problems especially if results for other tests are normal and there still persists an unexplained cause of infertility. The test indicates if the chemical composition of the mucus is appropriate for sperm survival and any dead or slow moving sperm found indicates that the mucus is hostile.
During the test, following points have to be kept in mind:
* If the sperm delivered to the cervix is of good quality and quantity
* If the sperm mobility through mucus is vigorous
* If there’s indication of any kind of infection in either partner
And, even if the results of the test show presence of hostile mucus, the success rate of pregnancy can be improved through the Intrauterine Inception (IUI).
For normal fertility, sperm must be able to survive comfortably for a couple of days within the cervical mucus. But at times cervical mucus can become abnormally acidic and this change in pH can severely limit sperm survival. So, if for some reason cervical factor disease is the only causative factor, then Intrauterine Inception (IUI) is often recommended as the first treatment of choice. During the treatment, sperms can be placed above the cervical mucus inside a woman’s uterus and closer to the fallopian tubes to facilitate fertilisation. It is cost-effective and time saving treatment and the goal of IUI is to increase the number of sperms that reach the Fallopian tubes and subsequently increase the chance of fertilisation. IUI is often combined with ovulation inducing medicines such as follicle stimulating hormone which further increase the success rate.
However, if for some reason IUI treatment fails to show any positive results, then the couple may consider in-vitro fertilisation in which ovaries are fertilised with sperm in a laboratory and then after accessing the embryo quality these are placed in the uterus through the cervix.
Other line of treatments may include Estrogen therapy so as to improve the quality of mucus.
(The author is IVF expert, Indira IVF Hospitals, New Delhi )
Dr Arvind Vaid