Rarely, abnormal cervical mucus impairs fertility by inhibiting penetration or increasing destruction of sperm.
(See also Overview of Infertility.)
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.
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)
Abnormal mucus rarely impairs fertility significantly, except in women with chronic cervicitis or cervical stenosis due to prior treatment for cervical intraepithelial neoplasia.
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
Treatment may include intrauterine insemination and in vitro fertilization. However, whether either treatment is effective in women with abnormal cervical mucus is unproved.
Key Points
Abnormal cervical mucus rarely impairs fertility significantly, except in women with chronic cervicitis or cervical stenosis.
Do a pelvic examination to check for cervicitis and cervical stenosis.
Postcoital testing of cervical mucus is not useful.
Consider intrauterine insemination and in vitro fertilization.
