Isthmicocervical insufficiency

The anatomical reasons for the habitual miscarriage of pregnancy include ishmiko-cervical insufficiency, which is recognized as the most frequent etiologic factor of termination of pregnancy in the second trimester.

The incidence of ischemic-cervical insufficiency in patients with a habitual miscarriage is 13-20%. Pathognomonic signs of ismiko-cervical insufficiency are a painless shortening and the subsequent opening of the cervix in the second trimester of pregnancy, accompanied by prolapse of the bladder and / or outflow of amniotic fluid, ending with miscarriage or in the III trimester with the birth of a premature baby.

[1], [2], [3], [4], [5], [6], [7], [8]

Risk factors for ischemic-cervical insufficiency

• Injury of the cervix in history (posttraumatic isthmico-cervical insufficiency):
  • damage to the cervix in childbirth (ruptures not restored surgically, operative births through natural birth canals - obstetric forceps, genera of large fetus, fetus in pelvic presentation, fruit-destroying operations, etc.);
  • invasive methods of treatment of cervical pathology (conization, cervical amputation);
  • artificial abortions, termination of pregnancy at a later date.
• Congenital malformations of the uterus (congenital isthmico-cervical insufficiency).
• Functional disorders (functional istmiko-cervical insufficiency) - hyperandrogenia, connective tissue dysplasia, elevated serum retinax (noted in case of multiple pregnancy, induction of ovulation by gonadotropins).
• Increased stress on the cervix during pregnancy - multiple pregnancy, polyhydramnios, large fetus.
• Anamnestic indications for low-pain rapid termination of pregnancy in the II trimester or early premature birth. Methods of assessing the state of the cervix outside of pregnancy, as a rule, do not provide full information about the probability of development of ischemic-cervical insufficiency during pregnancy. Such an assessment is possible only with posttraumatic ischemic-cervical insufficiency, accompanied by gross violations of the anatomical structure of the cervix. In this situation, the GHA is performed on the 18-20th day of the menstrual cycle to determine the state of the internal pharynx. If the inner pharynx is enlarged by more than 6-8 mm, this is regarded as an unfavorable prognostic sign.

The question of the desirability of cervical plastics is solved together with the surgeon and gynecologist, taking into account the features of the patient's anamnesis (the number of late pregnancy interruptions, the inefficiency of therapy by other methods, including cervical stitching during pregnancy), the condition of the cervix, the possibility of surgical correction in each case. Most often, the plastic of the cervix outside the pregnancy is carried out according to Eltsov-Strelkov. Plastic surgery performed outside of pregnancy does not exclude surgical correction of the cervix during pregnancy. When performing plastic surgery outside of pregnancy, delivery is possible only by cesarean section because of the risk of rupture of the cervix with the transition to the lower uterine segment.

Prepare for pregnancy of patients with habitual miscarriage and ischemic-cervical insufficiency should begin with the treatment of chronic endometritis and normalization of the vaginal microflora. Due to the fact that the cervical blockage function is impaired, infection of the uterine cavity with a conditionally pathogenic flora and / or other microorganisms (chlamydial, ureaplasma, mycoplasma infections) occurs. Individual selection of antibacterial drugs is carried out with subsequent evaluation of the effectiveness of treatment according to the results of bacteriological examination, PCR, microscopy of the vaginal discharge.

Symptoms of ischemic-cervical insufficiency

Symptoms of isthmico-cervical insufficiency are as follows:

• sensation of pressure, raspiraniya, stitching pain in the vagina;
• discomfort in the lower abdomen and lower back;
• mucous discharge from the vagina, can be with blood veins; scanty spotting from the vagina.

It must be remembered that ischemic-cervical insufficiency can be asymptomatic.

In the foreign literature, ultrasound signs of ischemic-cervical insufficiency, obtained during examination by a transvaginal sensor, including those with stress tests (sample with pressure at the bottom of the uterus, a cough test, a positional test when the patient gets up) are described.

Measurement of the length of the cervix according to ultrasound can identify a group of increased risk of premature birth.

Until 20 weeks of gestation, the length of the cervix is very variable and can not serve as a criterion for the appearance in the future of premature birth. However, the pronounced dynamics of the cervix in a particular patient (shortening, opening of the internal pharynx) indicates an isthmic-cervical insufficiency.

In 24-28 weeks, the average length of the cervix is 45-35 mm, 32 weeks and more - 35-30 mm. Shortening of the cervix to 25 mm or less in a period of 20-30 weeks is a risk factor for premature birth.

Criteria for diagnosis of ischemic-cervical insufficiency during pregnancy

• Anamnestic data (malignant late miscarriage) or rapid premature birth, with each subsequent pregnancy at an earlier gestational age.
• Prolapse of the bladder into the cervical canal in the outcome of the previous pregnancy.
• Ultrasound data - shortening of the cervix less than 25-20 mm and opening of the internal pharynx or cervical canal.
• Softening and shortening of the vaginal part of the cervix when it is examined in mirrors and vaginal examination. Recent studies have shown that stituting the cervix in women with ischemic-cervical insufficiency reduces the incidence of very early and early premature births to 33 weeks gestation. However, it was noted that such patients require the use of tocolytic drugs, hospitalization, antibiotic therapy, in contrast to patients who were prescribed only bed rest.

[9], [10], [11], [12], [13], [14], [15], [16]

Monitoring the state of the cervix during pregnancy

In patients at high risk (with a habitual miscarriage of pregnancy in the second trimester), monitoring of the cervix should be performed at 12 weeks of gestation if there is a suspicion of posttraumatic ischemic-cervical insufficiency, from 16 weeks - if functional istmico-cervical insufficiency is suspected for at least a two-week interval, if necessary, weekly. Monitoring includes examination of the cervix in the mirrors, vaginal examination and, if necessary, ultrasound evaluation of the length of the cervix and the condition of the internal pharynx.

Treatment of ischemic-cervical insufficiency

Surgical correction during pregnancy with developed istmiko-cervical insufficiency in combination with bed rest is more effective than just bed rest.

The most common methods of surgical correction of ischemic-cervical insufficiency was the imposition of sutures along the Shirodkar, McDonald in modifications, the L-shaped seam according to Lyubimova.

The following conditions are necessary for surgical correction of ischemic-cervical insufficiency:

• a living fetus without developmental defects;
• term of pregnancy is not more than 25 weeks;
• a whole fetal bladder;
• normal tone of the uterus;
• absence of signs of chorioamnionitis;
• absence of vulvovaginitis;
• absence of bloody discharge from the genital tract.

Management of the postoperative period includes administration of antispasmodic agents (drotaverina hydrochloride 40 mg twice daily IM), antibiotic therapy, if necessary (with increased tone of the uterus) - tocolytic therapy.

When conducting pregnancy after sewing the cervix, it is necessary to carry out the bacterioscopy of the vaginal discharge and examine the condition of the joints on the cervix every 2 weeks, if there are pathological discharge from the genital tract, the examination is performed more often, taking into account the indications. Indications for the removal of stitches from the cervix:

• term of pregnancy - 37 weeks;
• at any period of pregnancy when leakage or outflow of amniotic fluid, bloody discharge from the uterine cavity, suturing (fistula formation), the beginning of regular labor.

In complicated cases, when the vaginal portion of the cervix is so small that it is impossible to sew transvaginally (after amputation of the cervix), seams are transabdominally laparoscopic (in the world literature, about 30 such operations are described during pregnancy).