Hostile Cervical Mucus and Infertility

Inadequate production or quality may cause infertility

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As odd as it may sound, the term hostile cervical mucus is a pretty appropriate description of a condition where cervical fluids are less than ideal for achieving pregnancy. It is one of many possible causes of unexplained infertility and can occur alongside other well-known factors.

In some cases, cervical mucus hostility may be the result of a drug side effect, including antihistamines and certain infertility drugs. Age, infections, and hormonal imbalances are also common causes.

Role of Cervical Mucus in Pregnancy

Cervical mucus is essential to achieving pregnancy as it creates the ideal environment by which semen can thrive and move freely.

Just before ovulation, cervical fluids will increase and become more like raw egg whites in their consistency. In this form, the cervical mucus actively nourishes sperm cells and enhances their ability to move through the cervical canal.

Any problems with the mucus can impede this process and make getting pregnant all the more difficult. It is estimated that anywhere between three percent and eight percent of female infertility cases are caused by cervical mucus hostility.

Causes of Cervical Mucus Hostility

Cervical mucus hostility is a term that can refer to any number of possible problems with cervical fluids. Among some of the more common causes:

  • Thick, dry, or sticky mucus is often caused by hormonal imbalances and frequently co-occurs with ovulation problems. A thickened consistency directly interferes with sperm motility.
  • Acidic mucus creates an environment hostile to sperm. While hormonal irregularities can interfere with pH balance, the acidity may also be the result of a bacterial or yeast infection.
  • Inflammatory cells are produced in response to an infection. When this happens in the vagina or cervix, the cells can actively target and kill sperm.
  • Anti-sperm antibodies are defensive proteins produced by the immune system in response to a past infection where sperm was either present or involved. While less common, these antibodies can also attack and kill sperm.

Treatment of Hostile Cervical Mucus

When diagnosed, treatment of cervical mucus treatment can vary based on the underlying causes and other contributing factors (including age, smoking, and medication use). This may involve:

  • Treating any vaginal or cervical infection with an antibiotic or antifungal
  • Changing treatment or lowering the Clomid (clomiphene) dosage as higher doses may cause mucus hostility
  • Reducing antihistamine use as this can also interfere with mucus production
  • Prescribing a short-term course of ethinyl estradiol, a synthetic estrogen, which tends to improve the production and quality of cervical mucus
  • Taking over-the-counter cough remedy containing guaifenesin, an expectorant known to thin cervical mucus
  • Using a fertility friendly lubricant if there is no indication of either infection or anti-sperm antibodies

In some cases, in vitro fertilization (IVF) may be explored if these treatment efforts fail and infertility persists.

While some people will suggest that drinking more water or eating less dairy may help, there is currently no evidence that either will enhance the quality or production of cervical mucus.

View Article Sources
  • Nakano, F.; Leão, R.; and Esteves, S. (2015) “Cervical Hostility and Vaginal pH in Females with Unexplained Infertility.” In: Schattman, G.; Esteves, S.; and Agarwal, A. (eds). Unexplained Infertility. New York, New York: Springer.