Uterine Fibroid Embolization Procedure

EMBOLIC AGENTS | PREGNANCY AFTER UAE

Pregnancy after Uterine Embolization

The long-term effect that UAE may have on a woman's ability to have a child is not known. It may reduce chances of becoming pregnant for some women, but in others it may be just as likely that the chances will increase.

There are a number of ways that pregnancies may be affected by UAE. During the procedure, some of the flow in the uterine arteries is decreased at least temporarily. It is uncertain what effect this will have on the ability to become pregnant or to carry a pregnancy to term. It appears that in most patients, the arteries reopen to the normal parts of the uterus and it is rare for there to be a permanent injury to the uterus. As the fibroids die and begin to shrink, in some cases this may weaken the wall of the uterus. This would appear to be most likely with large fibroids that span the entire wall of the uterus. However, fibroids compress the normal uterine tissue adjacent to them and as they shrink, we have seen the normal tissue restored to a more normal configuration. For any individual, it is difficult to predict whether the uterus will be weakened to the point where there might be a problem during delivery of a baby. For our patients that have become pregnant, we recommend that a sonogram be performed to assess the site of implantation and the overall integrity of the uterine wall.

Another potential effect of this procedure is the loss of menstrual cycles, with the onset of menopause. The overwhelming majority of women who have had embolization of fibroids have had decreased bleeding with normal menstrual cycles. There have been a few women (most of whom are near the age when menopause would be expected) who have lost their menstrual periods after uterine embolization. The cause is most likely decrease in blood supply to the ovaries as a result of the embolization. Most researchers have noted a 2 to 6% chance of losing menstrual periods and the onset of menopause as a result of UAE (1-4). There has been one study that noted a higher rate of menopause after the procedure (15% of patients treated) but the reason for this higher rate is not clear (5). It is very rare for a woman under the age of 45 to lose menstrual periods.

To further evaluate ovarian function after UAE, at Georgetown, we have completed a study on ovarian function after uterine embolization (6). Among the 35 women in the study under the age of 45, there was no permanent change in FSH, a hormone often used to estimate the likelihood of pregnancy. None of the women in that study had cessation of menstrual periods.

Published Data
Thus far, over 100 patients have become pregnant after this procedure worldwide. There have been two papers summarizing pregnancy after UAE (7, 8). In Ravina's study, among 184 women who had uterine embolization, 12 unexpected pregnancies occurred during the follow-up period. The average age of this group of patients was 36. There were 5 miscarriages (in 3 women) among the 12 pregnancies. There were 7 deliveries, 4 by cesarean. There was 1 twin pregnancy. There was one baby that died during delivery from an infection. The mother in this case had AIDS and had a serious streptococcal infection at the time of the delivery. The other 7 babies were all normal. In McLuca's study, there were 52 women under the age of 40 who stated an interest in pregnancy. Of these there were 17 pregnancies in 14 patients, for a 33% pregnancy rate. There were 10 term pregnancies, 5 miscarriages, and 2 ongoing pregnancies at the time of publication.

Both of the above studies are small and are not of sufficient size to determine overall fertility rates. However, there are other sources of data on pregnancies after uterine embolization. For example, it is also known that patients who have had this procedure for other reasons, such as bleeding after childbirth, have successfully carried pregnancies (9).

At this time there is insufficient information to predict the percentage of women who will be able to become pregnant after UAE. It is very likely that the chance of pregnancy will depend on the extent of the fibroids. Those patients with very extensive fibroids are probably less likely to become pregnant whether they have UAE, myomectomy or even if they have no therapy at all.

It is hoped that the FIBROID registry will answer the question about subsequent pregnancies after UAE. Until that data is available, each patient's treatment will need to be carefully considered and UAE recommended in those patients in whom other more established therapies have failed or are likely to reduce fertility further.

References

Hutchins F, Worthington-Kirsch R, Berkowitz R. Selective uterine artery embolization as primary treatment for symptomatic leiomyomata uteri. J Am Assoc Gynecol Laparosc 1999;6:279-284.

McLucas B, Adler L, Perella R. Uterine Fibroid Embolization: Nonsurgical treatment for symptomatic fibroids. J Am Coll Surg 2001;192:95-105.

Ravina J, Ciraru-Vigneron N, Aymard A, Ferrand J, Merland J. Uterine artery embolisation for fibroid disease: results of a 6 year study. Min Invas Ther & Allied Technol 1999;8:441-447.

Spies J, Ascher SA, Roth AR, et al. Uterine Artery Embolization for Leiomyomata. Obstet and Gynec 2001;98:29-34.

Chrisman H, Saker M, Ryu R, et al. The impact of uterine fibroid embolization on resumption of menses and ovarian function. JVIR 2000;11:699-703.

Spies J, Roth A, Gonsalves S, Murphy-Skrzyniarz K. Ovarian function after uterine artery embolization: assessment using serum follicle-stimulating hormone assay. J Vasc Interv Radiol 2001;12:437-442.

McLucas B, Goodwin S, Adler L, et al. Pregnancy following uterine fibroid embolization. Int J Gynaecol Obstet 2001;74:1-7.

Ravina J, Vigneron N, Aymard A, Le Dref O, Merland J. Pregnancy after embolization of uterine myoma: report of 12 cases. Fertility and Sterility 2000;73:1241-1243.

Deux J, Bazot M, Le Blanche A, et al. Is selective embolization of uterine arteries a safe alternative to hysterectomy in patients with postpartum hemorrhage? AJR 2001;177:145-149.