Figure 15.3 MR images. A: Degenerating fibroid. Left to right. Preenhanced T1 image, T2 image, and no enhancement on T1 Gd-DPTA at 60 seconds. B: Leiomyosarcoma. Left to right, preenhanced T1 image, T2 image (arrow to dorsal part of tumor), and enhancement of dorsal part of tumor (arrow) on T1 Gd-DPTA at 60 seconds. (From Goto A, Takeuchi S, Sugimura K, et al. Usefulness of Gd-DTPA contrast-enhanced dynamic MRI and serum determination of LDH and its isozymes in the differential diagnosis of leiomyosarcoma from degenerated leiomyoma of the uterus. Int J Gynecol Cancer 2002;12:354–361.) women had no increase in fibroid volume throughout pregnancy (69). In the 31% of women noted to have an increase in volume, the greatest increase occurred before the 10th week of gestation. There was no relationship between initial fibroid volume and fibroid growth during gestational periods. A reduction in fibroid size toward baseline measurements was observed 4 weeks after delivery.
In women noted to have fibroids during pregnancy, clinical symptoms and sonographic evidence of fibroid degeneration occurs in about 5% (70). Among 113 women followed during pregnancy with serial sonography, 10 (9%) developed anechoic spaces or coarse heterogenous patterns consistent with fibroid degeneration. Seven of 10 women had severe abdominal pain requiring hospitalization, consistent with clinical symptoms of degeneration. No sonographic changes were noted in the other 103 women, and only 11.7% had similar abdominal pain. A small study of women with fibroid-associated pain during pregnancy found use of ibuprofen shortened the hospital stay and decreased the rate of readmission (71).
Inﬂuence of Fibroids on Pregnancy
Very rarely does the presence of a fibroid during pregnancy lead to an unfavorable outcome.
Research was conducted on large populations of pregnant women examined with routine second trimester sonography with follow-up care and delivery at the same institution (72,73). In a study of 12,600 pregnant women, the outcomes of 167 women with fibroids were no different with regard to the incidence of preterm delivery, premature rupture of membranes, fetal growth restriction, placenta previa, placental abruption, postpartum hemorrhage, or retained placenta (72). Cesarean section was more common among women with fibroids (23% vs. 12%).
The other study of 15,104 pregnancies, including 401 women with fibroids, found no increased risk of premature rupture of membranes, operative vaginal delivery, chorioamnionitis, or endometritis (73). However, there were increased risks of preterm delivery (19.2% vs. 12.7%), placenta previa (3.5% vs. 1.8%), and postpartum hemorrhage (8.3% vs. 2.9%). Cesarean section was again more common (49.1% vs. 21.4%).
Fetal injury attributed to mechanical compression by fibroids is uncommon. A search of the PubMed database from 1980 to 2010 revealed one case of fetal head anomalies with fetal growth restriction, one case of a postural deformity, one case of a limb reduction, and one case of fetal head deformation with torticollis (74–75).
Any decision to perform a myomectomy in order to prevent problems during pregnancy should take into account the risks of surgery, anesthesia, postoperative adhesions, and an increased likelihood of subsequent cesarean delivery, along with concerns about discomfort, expense, and time away from work or family.
Rupture of Myomectomy Scar during Pregnancy