What Is A Bicornuate Uterus?

Gynecology

Obie Editorial Team

A bicornuate uterus is the most common congenital uterine anomaly and can impact a woman's reproductive capabilities. In the U.S., it is estimated that bicornuate uterus is seen in 1-5/1,000 women, though this may be an underestimate since not all are diagnosed, especially when they are not severe.

A bicornuate uterus is an abnormality of the uterus that has two horns and a heart shape. The uterus has a wall inside and a partial split outside. If necessary, a bicornuate uterus can be corrected surgically. Few studies of the surgery have been published. In three studies reporting on a total of 11 women, approximately 90% successfully carried a pregnancy to term.

Several studies show that women with a bicornuate uterus have about a 60% success rate in delivering a living child but have a higher risk of cervical incompetence. The condition is associated with an increased rate of spontaneous abortion, though the miscarriage rate is lower with a bicornuate uterus than with a septate uterus. That's probably because the blood supply to the midline indentation is better. Premature labor, a breech presentation and/or a retained or trapped placenta are also common complaints with a bicornuate uterus.

Diagnostic Procedures

A bicornuate uterus can be confirmed through use of the following techniques:

  • Pelvic exam: Two horns can occasionally be palpated. 
  • Sonogram: A bicornuate uterus can sometimes be diagnosed by ultrasound
  • Laparoscopy: Provides information on the exterior shape of the uterus. 
  • Hysteroscopy: Provides information on the interior configuration of the uterus.

Treatment

Metroplasty surgery: To create a large uterine cavity with minimal destruction of uterine tissue is the treatment of choice.
Cervical cerclage: Improved the fetal survival rate in selected patients. Both metroplasty and a cervical cerclage may be prescribed.

Pregnancy Outcome With Bicornuate Uterus And Other Anomalies 
  Live Birth Preterm Birth Ectopic Miscarriage
Arcuate Uterus  66.2% 5.1%   3.6%  20.1%
Uterine Septum  58.1%  10%  1.9%  75.7%
Bicornuate Uterus 62.5%  25%  25%
Didelphic Uterus 68.6%  24.4%  2.3%  20.9%
Unicornuate Uterus 54.2%  43.3%  4.3%  34.4%
Controls  82%  9-12%  2%  10-15%

References:


Raga. Hum Reprod 1997;12:2277
Fedele. Eur J Obstet Gynaecol 1995 
J Womens Health 2004