Pregnancy after uterine artery embolization for leiomyomata: the Ontario multicenter trial.

OBJECTIVE: To report on pregnancies and deliveries occurring in a large cohort of women who underwent uterine artery embolization instead of surgery for symptomatic leiomyomata.
METHODS: A total of 555 women underwent uterine embolization in a multicenter clinical trial. The primary embolic agent was 355-500 microm polyvinyl alcohol particles with treatment end-point as bilateral stasis in the uterine arteries. Women desiring pregnancy were informed of the uncertain effect of embolization on fertility and pregnancy. Average age at embolization was 43 years (range 18-59 years). Thirty-one percent were younger than age 40 years. Women were followed up prospectively by telephone, and obstetric records of the women who conceived were reviewed.
RESULTS: Twenty-one women of average age 34 years (range 27-42 years) conceived, (3 of these twice), and 13 women were nulliparous. Twenty-three of the 24 pregnancies were conceived spontaneously (1 woman had in vitro fertilization). There were 4 spontaneous abortions (16.7%, 95% confidence interval 5.4-41.9%) and 2 elective pregnancy terminations. Fourteen of the 18 live births were full term and 4 were preterm. There were 9 vaginal deliveries and 9 cesarean deliveries, 4 of which were elective. Abnormal placentation occurred in 3 cases, all nulliparas (12.5% 95% confidence interval 3.1-36.3%). Two cases developed placenta previa (1 had a clinical partial accreta) and the third developed a placenta membranacea with accreta resulting in cesarean hysterectomy. Three postpartum hemorrhages all secondary to placental abnormalities occurred. Four newborns were small for gestational age (< or = 5th percentile); 2 of these pregnancies were complicated by gestational hypertension.
CONCLUSION: Women are able to achieve pregnancies after uterine artery embolization, and most resulted in term deliveries and appropriately grown newborns. Close monitoring of placental status, however, is recommended.