Large Uterine Fibroid in Pregnant Woman

A 36-year-old woman presented with a lump in her abdomen during her first pregnancy. She told clinicians she had noticed the lump before she became pregnant. She had no pain or other symptoms. The patient was a non-smoker, and had a body mass index of 26.6.

An ultrasound performed during her first trimester revealed a large fibroid in the fundus measuring 13 cm in diameter. The pregnancy proceeded free of complications, without development of high blood pressure, diabetes mellitus, or other disorders. The fetus grew normally to term. The size of the fibroid remained unchanged throughout the pregnancy.

At 38 weeks’ gestation, clinicians explained the potential immediate and long-term complications of cesarean myomectomy to the patient, and obtained her written informed consent for cesarean section. Clinicians performed the c-section with spinal anesthesia and a Pfannenstiel incision large enough to exteriorize the uterus and the fibroids.

The fetus was noted to be in the cephalic position. The patient’s hemoglobin level was 11 g/dL prior to surgery, and 9.6 g/dL postoperatively. Time in surgery was 50 minutes. A baby weighing 2,700 g was delivered by cesarean section, and the uterus was exteriorized.

Clinicians administered a bolus push of 10 IU of oxytocin intravenously to induce uterine contractions. They noted a large intramural fibroid 20 cm in diameter in the right fundus and two smaller fibroids in the left fundus.

The surgeon used new incisions in the uterus rather than the cesarean section incision. The large fibroid measuring 22 × 19 × 9 cm was successfully removed, followed by removal of the smaller fibroids.

Clinicians injected 500 mg of tranexamic acid to aid hemostasis. No blood transfusions were needed. They repaired the uterine wall with a continuous suture using Monosyn, and sent the three fibroids for histopathological examination.

Clinicians’ diagnosis of fibroids with cystic and hyaline degenerations was confirmed by the pathology report. Mother and baby recovered well after surgery, and were discharged home 3 days later.

Discussion

Clinicians reporting this second of two cases of successful cesarean myomectomy of large intramural fibroids noted that the fertility of their patients was not affected by the fibroids. “Both patients were nulligravida and became pregnant within 1 year following marriage,” they wrote.

Fibroids can occur at any age, and occur in 30% to 40% of women ages 30 to 40.

The effect of a fibroid on fertility depends on its site in the uterus, the authors noted. Submucosal fibroids are associated with a 27% pregnancy rate compared with a 41% rate in patients with intramural fibroids. Myomectomy has not been conclusively demonstrated to increase fertility, the authors added.

Nevertheless, they pointed to an analysis of pregnancy and miscarriage rates in 181 women with uterine fibroids who had been trying to conceive for at least 1 year without success. The main outcome measures were pregnancy rate and miscarriage rate.

Among the patients who underwent myomectomy, pregnancy rates were 43.3% with submucosal fibroids, 56.5% with intramural fibroids, 40.0% with submucosal-intramural fibroids, and 35.5% with intramural-subserosal fibroids compared with rates of 27.2%, 41.0%, 15.0%, and 21.43%, respectively, among the patients who did not undergo surgery.

The case authors explained that because both of their patients lived in small cities, they opted for cesarean myomectomy to avoid having to return to the tertiary hospital for fibroid removal. Clinicians informed both patients of potential uterine rupture and the need to attend a tertiary hospital for antenatal care for subsequent pregnancies.

Fibroids in women during pregnancy may result in intrauterine growth retardation, placental abruption, placenta previa, postpartum hemorrhage, and retained placenta, the authors noted. They are also associated with a higher likelihood of delivery via cesarean section compared with women without fibroids (48.5% vs 13.3%, P<0.05).

The patients’ fetuses were in the cephalic position, and there was no malpresentation. “The risk of malpresentation of the fetus in women with fibroids is 13%, which is higher than in women without fibroids (4.5%),” the authors wrote.

Both malpresentation and risk of cesarean section are primarily related to the fibroids’ location, they explained. Fibroids in the lower segment of the uterus can interfere with fetal head engagement. During pregnancy, the most common complaint due to fibroids is pain, usually during the second and third trimesters and in women with large fibroids (>5 cm), the authors noted; this is usually caused by red degeneration and torsion of the pedunculated subserosal fibroid.

While the two patients’ fibroids exhibited hyaline and cystic degenerations, they did not experience pain during pregnancy. One year later, a follow-up assessment found both infants healthy, and their mothers (who were both taking oral contraceptives) had returned to a normal menstrual cycle without any complaints.

No standard guidelines have been developed regarding cesarean myomectomy; treatment of fibroids in pregnancy varies between centers, “particularly regarding whether the fibroids should be removed during cesarean section,” the authors wrote.

Fibroids with a diameter exceeding 5 cm are considered large. One study showed that cesarean myomectomy is safe for large fibroids, with “no difference in mean change of the hemoglobin level before and after surgery between cesarean myomectomy and cesarean without myomectomy.” However, the case authors cautioned that this particular study did not include fibroids >15 cm in size.

Another study of 2,565 women with fibroids in pregnancy showed that 9.4% underwent cesarean myomectomy safely, and “there was no difference in blood loss between cesarean myomectomy and cesarean section only,” the case authors noted.

One review showed that women who underwent a cesarean myomectomy had a 0.30 g/dL greater drop in hemoglobin compared with women who had a cesarean section only, but this difference was not statistically significant.

The case authors noted that cesarean myomectomy in their two patients with fibroids >15 cm resulted in blood losses of 400 and 500 mL, respectively. They advised clinicians to minimize bleeding by performing myomectomy only after the cesarean section incision has been closed, “unless the fibroid is to be removed via the same incision. Depending on the location of the fibroid, if it is not around the incision, we make a new incision above the fibroid.”

Following their patients’ myomectomies, they sutured the uterine wall immediately with one to two layers of sutures (based on the uterine wall thickness), then tranexamic acid was administered to promote hemostasis, though they noted that the data on the effectiveness of this measure are mixed.

“Cesarean myomectomy only added around 10 minutes to the time needed for cesarean section. The mean operative time for cesarean myomectomy was 53.3 ± 18.6 minutes,” they wrote. “The operative time of cesarean myomectomies for large fibroids in this report was acceptable (50 and 70 min, respectively).”

The safety of cesarean myomectomy for a large fibroid relies on “adequate preparation, expertise in pelvic surgery, patient selection, and the hospital facilities,” they added. “Cesarean myomectomy should only be performed at tertiary hospitals where experts and adequate intensive care facilities are available,” as in these two reported cases.

They concluded that their experience with these two patients showed that “cesarean myomectomy for a large fibroid is safe, even for fibroids >15 cm in diameter … Further larger studies of cesarean myomectomy for large fibroids are required to confirm the safety of this procedure.”