Fibroid Surgery Reduces Miscarriages in Certain Women

Recurrent miscarriage is defined as a condition where a woman suffers 3 or more consecutive miscarriages at less than 24 weeks gestation.   Though some patients have known cause like genetic, hormonal or immunological, in many others, the cause is not known. 

Fibroids are benign muscular tumors arising from the wall of the uterus.  They may be submucosal i.e. arise just below the inner lining of the uterus, intramural i.e. within the wall of the uterus or subserosal i.e. just below the outer lining of the uterus.  Submucosal fibroids have been mainly associated with infertility. 

Are fibroids associated with recurrent miscarriage?  If so, does removal of a fibroid reduce the chances of a repeat miscarriage?  A study was carried out to answer these questions and the results were recently published in the Human Reproduction Journal.

Women suffering repeated miscarriages were included in the study.  They underwent two investigations to diagnose the presence of uterine abnormalities- transvaginal ultrasonography (a procedure in which the ultrasound probe is introduced into the vagina) and hysterosalpingography, (a procedure in which a dye is introduced into the uterus and the structure of the uterus studied using imaging techniques). 

In the study, 8.2% women with repeated miscarriages had fibroids.  Earlier studies indicate that fibroids are present in 1-2.4% women with infertility.  Thus, fibroids were more common in women with recurrent miscarriages than with infertility.

The study found that 2.6% fibroids were submucosal and 5.6% were intramural or subserosal.  Submucosal fibroids tend to distort the uterine cavity and may have to be removed.  In this study, only women with submucosal fibroids or with a mixed type of submucosal plus intramural fibroids underwent surgery to remove the fibroids. Hysteroscopy, a less invasive surgical procedure to remove fibroids was performed in 22 patients, whereas 3 patients underwent laparoscopy or laparotomy to remove the fibroids.

In women with submucosal fibroids, 16% suffered from painful menstruation and 32% suffered from heavy bleeding prior to surgery.  Improvement was noted in these cases following surgery.

Women with fibroids distorting the uterine cavity had a miscarriage rate of 76.7% and a live birth rate of 23.3%.  The rates were similar in women with fibroids not distorting the uterine cavity.

Fibroids distorting the uterine cavity resulted in a mid-trimester miscarriage (between fourth to sixth months of pregnancy) rate of nearly 1 in every 5 pregnancies.  This implies that any women with a mid-trimester miscarriage should be investigated for the presence of fibroids.

After referral to a tertiary center and undergoing surgery, women with fibroids distorting the uterus conceived after a mean if 6.4 months.  The miscarriages in the mid-trimester dropped from 21.7 to 0.0%, thus resulting in an increase in live birth rate from 23.3 to 52.0%.  Thus, mid-trimester miscarriages can be avoided with surgery for fibroids causing uterine distortion.

The live birth rates in women with fibroids not distorting the uterine cavity also increased to 70.4% after referral to a tertiary center despite no intervention.  Thus, surgery may not be required for these types of patients and the rate of successful pregnancies can be improved with supportive care only.

The study also indicates that women with large fibroids without distortion of the uterus can also have successful pregnancies.

A more detailed study should be carried out to confirm the findings that surgery in patients with recurrent miscarriages and distorting the uterine cavity is indeed beneficial.

Reference:

Human Reproduction. 2011;26(12):3274-3279.; Sotirios H. Saravelos; Junhao Yan; Hassan Rehmani; Tin-Chiu Li.

Source-Medindia