INTRODUCTION

Incompetent cervix is a condition where recurrent mid-trimester pregnancy loss complicates a pregnancy. Incompetent cervix is diagnosed in I in 2000 pregnancies, and has been determined as the cause of approximately 15% of all recurrent pregnancy loss. 

BACKGROUND

Many risk factors have been implicated as causes for incompetent cervix such as, birth trauma to the maternal cervix, muscular cervix, exposure to DES in utero, Müllerian anomalies, and congenital anomalies. In clinical practice, however, there may be no identifiable cause for this devastating condition.

DIAGNOSIS

The diagnosis can be made either by poor obstetric history or by examination. In the absence of poor obstetric history, the classic presentation of incompetent cervix is rapid and painless second trimester loss. However, the more common presentation of this condition is pregnancy loss accompanied by some degree of symptoms. Vaginal spotting, vaginal discharge, and pelvic pressure are the symptoms described most often by these patients.

Recent advances in medicine have resulted in the early diagnosis of incompetent cervix with transvaginal ultrasonography. Asymptomatic cases can now be diagnosed earlier than before, prior to advanced cervical dilatation, funneling of the lower uterine segment, or prolapsing of fetal membranes into the vagina. Ultrasound plays a big role in the management of cases that are only suspicious for cervical incompetence. By performing serial transvaginal sonography, changes in the cervix can be detected, allowing for other management options to be offered to the patient. 

Treatment

The cerclage is basically a method of strengthening of the cervix by placing a circumferential suture at the level of the internal cervical os. A cerclage can be placed either vaginally (most common) or abdominally (less common). There are different modifications of the vaginal cerclage, such as McDonald cerclage, Shirodkar cerclage, etc. Although they differ in surgical techniques, these operations are considered equally efficacious, and allow for possible vaginal delivery. The abdominal cerclage, as the name may imply, requires major abdominal surgery with subsequent delivery via cesarean section. This approach is usually reserved for patients who have failed vaginal cerclage, or who have either a significant anatomical cervical deformity or an atrophied cervix for which the vaginal approach is not feasible.

Despite the fact that prophylactic cerclage is considered the standard treatment of incompetent cervix, the best and most effective treatment is yet to be determined through clinical randomized trials. Nevertheless, patients with classic history of incompetent cervix should be offered cerclage. Patients who have received prophylactic cerclage may be followed with serial sonographic studies to detect and monitor any ongoing cervical changes. In patients where past obstetric history is concerning or suspicious for cervical incompetence, conservative but close management, i.e., bed rest, serial sonographic evaluation of the cervix, may be offered. 

Follow-up

Patients who have received prophylactic cerclage usually assume modified physical activities. Although standardized monitoring plans are lacking, close prenatal visits and serial sonographic cervical monitoring may be beneficial. When the gestational age reaches 36-37 weeks, the cerclage may be removed in the office, and the patient may then be followed expectantly. In cases of abdominal cerclage, delivery is usually accomplished via cesarean section after documentation of fetal lung maturity at 36-37 weeks.  

CONCLUSION

Today's ultrasound technology has greatly improved the diagnostic ability of obstetricians in determining incompetent cervix, with early diagnosis offering more treatment options. For the patient managed either by cerclage, serial ultrasound, or both, the technology quite often results in a more successful pregnancy outcome.