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Abnormal Cervical Mucus


Robert W. Rebar

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

Last review/revision Sep 2022
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Rarely, abnormal cervical mucus impairs 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. If cervicitis is suspected because women have cervical exudate (purulent or mucopurulent) or cervical friability, a cervical swab is done to test for gonorrhea and chlamydial infection. 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

  • Antibiotics, if cervicitis is present

  • Sometimes cervical dilation for cervical stenosis

  • Sometimes 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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