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Abnormal Cervical Mucus


Robert W. Rebar

, MD, Western Michigan University Homer Stryker M.D. School of Medicine

Last full review/revision Sep 2020| Content last modified Sep 2020
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Abnormal cervical mucus may impair fertility by inhibiting penetration or increasing destruction of sperm.

Normally, cervical mucus is stimulated to change from thick and impenetrable to thin and stretchable by an increase in estradiol levels during the follicular phase of the menstrual cycle Menstrual Cycle Hormonal interaction between the hypothalamus, anterior pituitary gland, and ovaries regulates the female reproductive system. The hypothalamus secretes a small peptide, gonadotropin-releasing... read more .

Abnormal cervical mucus may

  • Remain impenetrable to sperm around the time of ovulation

  • Promote sperm destruction by facilitating influx of vaginal bacteria (eg, due to cervicitis)

  • Contain antibodies to sperm (rarely)

Diagnosis of Abnormal Cervical Mucus

  • Examination to check for cervicitis and cervical stenosis

A pelvic examination is done to check for cervicitis and cervical stenosis. Cervicitis is diagnosed if women have cervical exudate (purulent or mucopurulent) or cervical friability. Complete cervical stenosis is diagnosed if a 1- to 2-mm diameter probe cannot be passed into the uterine cavity.

Postcoital testing of cervical mucus to determine whether viable sperm are present (which used to be routine during infertility evaluation) is no longer considered useful because results do not correlate with subsequent pregnancy rates.

Treatment of Abnormal Cervical Mucus

  • Assisted reproductive techniques (intrauterine insemination or in vitro fertilization)

There is no evidence that using drugs to thin the mucus (eg, guaifenesin) improves fertility.

Key Points

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