Effect of endometriosis on IVF/ICSI outcome: stage III/IV endometriosis worsens cumulative pregnancy and live-born rates

Human Reproduction Vol.20, No.11 pp. 3130 3135, 2005 Advance Access publication July 8, 2005. doi:10.1093/humrep/dei176 Effect of endometriosis on IVF/ICSI outcome: stage III/IV endometriosis worsens cumulative pregnancy and live-born rates Paula Kuivasaari 1, Maritta Hippeläinen, Maarit Anttila and Seppo Heinonen Department of Obstetrics and Gynaecology, Kuopio University Hospital, 70211 Kuopio, Finland 1 To whom correspondence should be addressed. E-mail: kuivasaa@hytti.uku.fi BACKGROUND: Women with endometriosis often need IVF to conceive most women need several of treatment. METHODS: To evaluate the impact of moderate to severe endometriosis on cumulative IVF outcome, we carried out an observational study on 98 consecutive women who underwent IVF or ICSI treatment and had endometriosis diagnosed by laparoscopy or laparotomy and classified as minimal to mild endometriosis (American Society for Reproductive Medicine I/II) (n = 31) or moderate to severe endometriosis (American Society for Reproductive Medicine III/IV) (n = 67). The reference group consisted of 87 consecutive women with tubal infertility. The main outcome measures were cumulative pregnancy and live birth rates. RESULTS: There was a significantly lower pregnancy rate per fresh embryo transfer after pooled (1 4) among women with stage III/IV endometriosis (22.6%) compared to stage I/II group (40.0%) or tubal infertility (36.6%). After 1 4 IVF/ICSI treatments, including frozen embryo transfer, 56.7% of the women with stage III/IV endometriosis were pregnant and 40.3% gave birth. The corresponding values were 67.7/55.8% when endometriosis was stage I/II and 81.6/43.7% in the controls respectively. CONCLUSION: Stage III/IV endometriosis means a worse prognosis for IVF/ICSI treatments compared to milder stages or tubal factors. Lower implantation and multiple pregnancy rates offer some support to our practice to continue two embryo transfers in this group. Key words: embryo transfer/endometriosis/infertility/ivf and ICSI outcome/pregnancy Introduction Endometriosis is a disease of reproductive-aged women characterized by endometrial glands or stroma in sites other than the uterine cavity, usually the peritoneum or ovaries. Endometriosis is one of the most challenging diseases for gynaecologists helping infertile women to conceive. Many factors have been suggested to cause infertility in women with endometriosis, including pelvic adhesions, ovulatory dysfunction, disturbed folliculogenesis and defective implantation (Pellicer et al., 1995; Cahill et al., 1997; Selam and Arici, 2000; Navarro et al., 2003; Brosens et al., 2004). Using IVF it is possible to bypass some disturbances of reproductive function. Several studies have shown that women with endometriosis have a lower ovarian response to gonadotrophins (Azem et al., 1999; Al-Azemi et al., 2000; Aboulghar et al., 2003). In addition, Al-Azemi et al. (2000) found that women with endometriosis needed more HMG ampoules per cycle, while the control group of tubal factor subjects maintained a constant ovarian response over the five analysed. One reason for a reduced ovarian response may be previous ovarian resection. Aboulghar et al. (2003) investigated women with severe endometriosis who had had previous surgical treatment and found that these patients had a significantly higher withdrawal rate than the control group with tubal infertility. Of the endometriosis patients, 29.7% discontinued because of poor ovarian response, the corresponding rate for tubal factor patients being only 1.1%. In contrast, in a study carried out by Donnez et al. (2001), preceding vaporization of the internal cyst wall of endometriomas did not impair ovarian function; there were no differences in ovarian response to stimulation between women with endometriosis and women with tubal infertility. Data on the impact of endometriosis on the results of IVF treatment are controversial. Olivennes et al. (1995) found that pregnancy rates were no different from those of women with tubal infertility, whereas Bergendal et al. (1998) found that patients with endometriosis had a reduced response to ovarian stimulation, a lower number of oocytes and a reduced fertilization rate, but not a reduced pregnancy rate. In a recent metaanalysis of 22 published studies (Barnhart et al., 2002) the conclusion was that women with endometriosis have a reduced pregnancy rate (<35%) compared with that in women with tubal infertility. In addition, other indicators, such as circulating estradiol levels, numbers of retrieved oocytes, and decreased fertilization and implantation rates, have shown similar results (Azem et al., 1999). Furthermore, the severity of endometriosis is likely to affect the outcome of assisted reproduction, women with stage III and IV disease having lower fertilization rates 3130 The Author 2005. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oupjournals.org

Effect of endometriosis on IVF/ICSI outcome compared with those with stages I and II. Overall, the data from the study carried out by Barnhart et al. (2002) suggest that endometriosis affects infertility not only by distorting normal pelvic anatomy but also by having effects on developing follicles, oocytes and embryos. The purpose of this study was to investigate whether or not the stage of endometriosis affects the outcome of IVF, and the specific aim was to look at the cumulative pregnancy and liveborn rates after four treatment using women with tubal infertility as a control group. Such data would be useful for patient counselling. Materials and methods The material consisted of 98 consecutive women who underwent IVF or ICSI treatment at Kuopio University Hospital between October 1996 and May 2003. All of them had endometriosis diagnosed by laparoscopy (77.6%) or laparotomy (22.4%). Endometriosis was scored according to the revised classification of the American Fertility Society (1997). In operation, adhesions were freed in 45 patients, endometriomas resected in 36 patients, and electrocoagulation was used in 46 cases. The control group comprised 87 consecutive women with tubal infertility. Tubal infertility was diagnosed by laparoscopy in 77.0% and by laparotomy in 6.9% of the women. In the rest of the women (16.1%) the diagnosis was made by hysterosalpingosonography (HSSG) (Spalding et al., 1998); they did not have any clinical signs of endometriosis and ultrasonography was clean. Excluded from the study were those women who: (i) had repeatedly high early cycle FSH level (>15 20 IU/l) and/or had no noticed follicles in ovaries by ultrasonography or no response after ovarial stimulation with high dose of FSH; or (ii) had seriously deformed uterus; or (iii) were aged >41 years; or (iv) had an infectious disease such as HIV. Only women whose partners semen analyses were normal were reviewed. The clinical details are given in Table I. A standard long IVF protocol with GnRH agonist and gonadotrophins was used. Buserelin (Suprecur ; Hoechst AG, Frankfurt, Germany) or nafarelin (Synarela ; Syntex Nordica AB Södertälje, Sweden) were started for down-regulation on the cycle days 20 22. When ovarian suppression was confirmed by ultrasound, recombinant FSH (rfsh, Gonal-F, Laboratories Serono; or Puregon, Organon, Oss, The Netherlands) or HMG (Menogon ; Ferring, The Netherlands) was used for controlled ovarian stimulation. Treatment was adapted Table I. Characteristics of the subjects Reference group Values are mean ± SD unless stated otherwise. *P < 0.05. **P < 0.01 in comparison with the reference group. Endometriosis stage I/II III/IV patients 87 31 67 Age (years) 33.7 ± 4.3 32.6 ± 4.4 30.8 ± 4.8** Body mass index (kg/m 2 ) 24.4 ± 4.5 23.1 ± 3.2 24.3 ± 4.3 Duration of infertility 4.2 ± 2.7 3.7 ± 2.3 3.4 ± 2.4 (years) Primary infertility (%) 39.4 61.3** 74.6** Smoking (>5 cigarettes 31.0 12.9** 13.4* per day, %) Chronic illness (%) 13/87 (14.9) 8/31(25.8) 7/67 (10.4) Ovarian resection 0 0 36/67 (53.7)** according to the response followed by sonography and carried out in an identical manner in the study and control groups. Doses of gonadotrophins were individually adjusted (range 150 300 IU) depending on patient s age, weight and ovarian response. When the largest one to three follicles reached a minimum diameter of 18 20 mm, HCG (Profasi, Ares-Serono; or Pregnyl, Organon, 5000 10 000 IU) was administered. Oocyte retrieval was performed 34 36 h later, using vaginal ultrasonography and the ova were fertilized on the same day. The luteal phase was supplemented with vaginal progesterone (Lugesteron, Leiras, Finland) started from the day before embryo transfer and continued until either a serum pregnancy test result was negative or gestational sac was confirmed on ultrasonography. ICSI was used according to our practice in all cases when there were only minimal findings to explain infertility and women had undergone unsuccessful inseminations before IVF-treatment was started, or just in case when there was severe endometriosis. If the number of oocytes retrieved was >10, ICSI was used in half of them. When all treatment were pooled, ICSI was used in 68, 44 and 37% of oocytes of the women with stage I/II, III/IV endometriosis or tubal infertility, respectively. The embryos were graded according to their morphology and cleavage stage. A scale of 1 5 was used, with class 1 being the best embryos. In this class, embryo cells are evenly sized, the blastomeres regularly shaped without fragments and the zona is intact. In class 2, the embryos are slightly non-homogeneous, the maximum fragmentation rate is 20% and the zona is solid. In class 3, the blastomeres are uneven in size and the fragmentation rate is 20 50%. In class 4, the fragmentation rate is >50%. Embryos of class 5 are not valid for transfer. Serum hcg concentrations were assayed 16 days after transfer to verify pregnancy. Thus, absolute pregnancy rate (detection of HCG) was reported. The assay was a Roche Diagnostics Elecsys HCG+b assay, involving use of the Roche Elecsys 2010 system (Roche, Mannheim, Germany). Clinical pregnancy was confirmed by the presence of gestational sac on vaginal ultrasonography. For comparison, the results of four similar studies identified through a Medline search were used to pool the outcome results. The search strategy was based on the key words endometriosis and IVF. Studies of a similar design (tubal infertility patients as a control group and patients with classified endometriosis as a study group) were included. Statistical analyses were carried out with SPSS version 11.0 software (SPSS Inc., Chicago, IL, USA). Statistically significant differences were determined using the χ 2 -test, Fisher s exact test or Student s t-test, as appropriate. P < 0.05 was considered statistically significant. Results Table II shows the overall outcomes of the IVF/ICSI separately for women in the reference group and women with minimal to mild or moderate to severe endometriosis. There were no statistically significant differences in the mean number of oocytes, fertilization rate or quality of embryos between the groups. The overall pregnancy rate per fresh embryo transfer was 31.7%, and of these pregnancies, 66.4% resulted in live-born infants in a total of 392 analysed in this study. These rates are comparable to those achieved in our unit in general. Detailed results are shown in Table II. Pregnancy rates after all four fresh embryo transfers were not significantly different in women with minimal to mild endometriosis and in the reference 3131

P.Kuivasaari et al. Table II. IVF/ICSI outcomes in four pooled after fresh embryo transfer Reference group Endometriosis stage I/II III/IV Age (years) 33.7 ± 4.3 32.6 ± 4.4 30.8 ± 4.8** 184 58 150 oocytes retrieved per cycle 9.3 ± 5.8 9.4 ± 5.7 8.7 ± 5.6 fertilized oocytes 4.8 ± 4.1 4.6 ± 3.7 4.5 ± 3.7 Fertilization rate (%) 884/1709 (51.7) 265/546 (48.5) 676/1306 (51.8) cleaved embryos 4.3 ± 3.9 3.8 ± 3.6 3.9 ± 3.7 grade 1 2 embryos 3.7 ± 3.6 3.1 ± 3.2 3.5 ± 3.6 embryos transferred 1.7 ± 0.7 1.7 ± 0.8 1.7 ± 0.8 Embryo not transferred (%) 20 (10.9) 8 (13.8) 17 (11.3) Implantation rate (%) 70/317 (22.1) 28/99 (28.3) 35/256 (13.7)* Pregnancy rate/embro transfer (%) 60/164 (36.6) 20/50 (40.0) 30/133 (22.6)** Miscarriage rate (%) 20/60 (33.3) 4/20 (20.0) 7/30 (23.3) Ectopic pregnancy (%) 4/60 (6.7) 0.0* 1/30 (3.3) Live birth (%) a 35/60 (58.3) 16/20 (80.0)** 22/30 (73.3) Live birth/ovarian puncture (%) 35/184 (19.0) 16/58 (27.6) 22/150 (14.7) Multiple births (%) 8/35 (22.9) 7/16 (43.8)** 4/22 (18.2) Values are mean ± SD unless stated otherwise. *P < 0.05. **P < 0.01 in comparison with the reference group. a Includes multiple births, committed as one. The fertilization rate was assessed for all retrieved oocytes, also for immature. group. When compared against the reference group, the pregnancy rate in women with moderate to severe endometriosis was significantly lower (P = 0.009). There were no significant differences in miscarriage rate between the groups. One pregnancy was terminated because of a fetal structural anomaly (anencephaly). Women with stage III/IV endometriosis had the highest overall drop-out rate from the treatment (52.2%). The drop-out rate was 38.7% in women with milder endometriosis and the corresponding rate was 44.8% in women with tubal factor infertility. There were no significant differences between these numbers. We recorded no differences in the mean numbers of oocytes yielded or the mean ages of women continuing their treatment versus those who dropped out (data not shown). Figure1 shows the cumulative live birth results. The cumulative pregnancy and live-born rates resulting from four IVF treatments without frozen embryo transfers were 64.5 and 51.6% in women with stage I/II endometriosis, 44.8 and 32.8% in women with stage III/IV endometriosis and 69.0 and 40.2% in the reference group respectively. With frozen embryo transfers (%) 60 50 40 30 20 10 0 1 2 3 4 Number of treatment Endometriosis I and II with frozen ET Endometriosis III and IV with frozen ET Tubal infertility with frozen ET Fig 1. Cumulative live birth rates (%) with and without frozen embryo transfer. included, the equivalent rates were 67.7 and 55.8% in women with stage I/II endometriosis, 56.7 and 40.3% in women with stage III/IV endometriosis and 81.6 and 43.7% in the reference group respectively. Finally, we compared the present results with those of four earlier studies having similar study design (Table III). The pooled data showed that the mean number of oocytes obtained per cycle and the pooled fertilization rate were significantly lower in women with endometriosis. Similarly, according to the pooled results, women with stage III/IV endometriosis also had a significantly lower pregnancy rate than the reference group, 14.3 versus 28% (P < 0.001). The corresponding rate was 23.1% in women with stage I/II endometriosis (P = 0.183). Women with minimal to mild endometriosis had a better livebirth rate (20.0%) than women with moderate to severe endometriosis (11.4%) or women with tubal factor infertility (18.7%). Discussion A poorer success with IVF with an increase in severity of endometriosis is also obvious according to our data. The overall cumulative outcome of IVF/ICSI treatment was favourable, however. It could be speculated that the results may have been even better if the women had been ready to continue treatments. The number of drop-outs was surprisingly large, especially among women with severe endometriosis (50%), and this may affect the overall results. Pregnancies in women with endometriosis more often resulted in live-born infants than those in the tubal factor group. Women with endometriosis had fewer miscarriages and ectopic pregnancies than women with tubal infertility, but on the other hand the women with tubal infertility were older and they smoked more often than those with moderate to severe endometriosis, which may be one reason for the observed higher rate of miscarriages. At the end, 3132

Effect of endometriosis on IVF/ICSI outcome Table III. Comparison of results in four earlier studies and in the present study (A) Mean ± SD numbers of oocytes NA = not applicable. oocytes oocytes P oocytes P Arici et al., 1996 9.5 ± 7.3 147 11.0 ± 6.1 43 0.221 5.3 ± 4.2 46 < 0.001 Azem et al., 1999 9.0 ± 5.3 197 NA NA NA 7.1 ± 4.8 207 < 0.001 Huang et al., 1997 9.9 ± 5.3 60 6.8 ± 3.9 27 0.003 7.6 ± 4.9 48 0.022 Matson and Yovich, 1986 4.3 ± 0.3 40 4.0 ± 0.4 61 < 0.001 3.2 ± 0.4 93 < 0.001 Present study 9.3 ± 5.8 184 9.4 ± 5.7 58 0.909 8.7 ± 5.6 150 0.340 Pooled 9.0 ± 5.8 628 7.6 ± 4.5 189 < 0.001 6.8 ± 4.6 544 < 0.001 (B) Fertilization rates (FR, %) FR FR P OR (95% CI) FR P OR (95% CI) Arici et al., 1996 70.1 147 66.8 43 0.179 0.86 (0.69 1.07) 78.4 46 0.008 1.55 (1.12 2.14) Azem et al., 1999 70 197 NA NA NA NA 40 207 < 0.001 0.64 (0.56 0.74) Huang et al., 1997 72.7 60 52.9 27 < 0.001 0.42 (0.3 0.59) 60.5 48 < 0.001 0.58 (0.44 0.76) Matson and Yovich, 1986 76.0 40 71.4 61 0.296 0.79 (0.50 1.23) 81.6 93 0.147 1.40 (0.89 2.21) Present study 51.7 184 48.5 58 0.193 0.88 (0.73 1.07) 51.8 150 0.957 1.00 (0.87 1.16) Pooled 64.1 628 59.2 189 < 0.001 0.81 (0.72 0.91) 52.0 544 < 0.001 0.61 (0.56 0.66) OR = odds ratio; CI = confidence interval; NA = not applicable. (C) Pregnancy rates (PR, %) PR% PR% P OR (95% CI) PR% P OR (95% CI) Arici et al., 1996 25.7 147 11.9 43 0.057 0.39 (0.14 1.05) 17.9 46 0.279 0.63 (0.27 1.45) Azem et al., 1999 22.4 197 NA NA NA NA 10.6 207 0.001 0.41 (0.24 0.71) Huang et al., 1997 32 60 27 27 0.639 0.79 (0.29 2.16) 22 48 0.248 0.60 (0.25 1.44) Matson and Yovich, 1986 18.0 40 13.1 61 0.501 0.69 (0.23 2.06) 3.4 93 0.004 0.16 (0.04 0.64) Present study 36.6 184 40.0 58 0.641 1.09 (0.58 2.03) 22.6 150 0.006 0.52 (0.31 0.86) Pooled 28.0 628 23.1 189 0.183 0.77 (0.53 1.13) 14.3 544 < 0.001 0.43 (0.32 0.58) OR = odds ratio; CI = confidence interval; NA = not applicable. (D) Live birth rates (LBR, %) LBR LBR P OR (95% CI) LBR P OR (95% CI) Arici et al., 1996 18.4 147 7.1 43 0.074 0.35 (0.10 1.18) 10.3 46 0.196 0.51 (0.18 1.43) Azem et al., 1999 16.6 197 NA NA NA NA 6.7 207 0.002 0.36 (0.19 0.70) Huang et al., 1997 NA 60 NA 27 NA NA NA 48 NA NA Matson and Yovich, 1986 NA 40 NA 61 NA NA NA 93 NA NA Present study 21.3 184 29.6 58 0.061 1.62 (0.82 3.21) 18.3 150 0.495 0.73 (0.41 1.31) Pooled 18.7 528 20.0 101 0.760 1.07 (0.63 1.83) 11.4 403 0.002 0.56 (0.38 0.81) OR = odds ratio; CI = confidence interval; NA = not applicable. more than half of the woman with minimal to mild endometriosis left the clinic with the baby, but only 40% of the women with tubal infertility or severe endometriosis. In addition to the overall outcome of the IVF/ICSI treatment, several interesting observations can be drawn from this study. First, women with moderate to severe endometriosis were treated earlier than women with less severe disease, although their infertility history was a few months shorter. Second, women with moderate to severe endometriosis discontinued infertility treatment more often than the other women. Third, the outcome of IVF/ICSI treatment was relatively constant within each group, independent of the order of the treatment cycle. Fourth, the rate of multiple pregnancies was highest in women with stage I/II endometriosis. 3133

P.Kuivasaari et al. The present results also have several clinical implications. The AFS classification is useful in predicting the outcome of infertility treatment and can be used for counselling purposes. Women with endometriosis should be treated in good time, especially when a woman has an active disease. The present results also support the idea of using single embryo transfer in women with stage I/II endometriosis, whereas the observed low pregnancy rate in women with stage III/IV disease requires further studies before deciding on an optimal policy in these cases. On the other hand, difficulties such as painful stimulation and challenging puncture, encountered by patients with endometriosis in the IVF treatment would favour the use of two-embryo transfer. Martikainen et al. (2001) investigated one- versus twoembryo transfer after IVF/ICSI. In that study the cause of infertility was not taken into consideration. The outcome was that two-embryo transfer did not result in a significantly better pregnancy rate than single embryo transfer; 47.1 versus 32.4%. Since our endometriosis III/IV group showed lower single and multiple pregnancy rates than the other groups, it is possible to draw the conclusion that their endometrial receptivity had deteriorated. However, on the basis of the results of a study by Diaz et al. (2000), this conclusion is not necessarily valid. In that study there were 25 women with stage III/IV endometriosis and 33 women with other causes of infertility. When oocytes from a single donor were donated to recipients in both groups, pregnancy, implantation and miscarriage rates were not found to be affected in women with endometriosis when compared with the control group. Further studies are therefore needed to address the issue of whether single embryo transfer should be recommended to women with moderate to severe endometriosis. All in all, we found that women with stage III/IV endometriosis had worse IVF/ICSI results compared with women with less severe disease or women with tubal infertility. Women with impaired ovarian reserve were excluded from our IVF programmes and this may somewhat bias the results. However, the effect of such bias would rather underestimate than overestimate the outcome difference between women with stage I/II and III/IV endometriosis. Overall, these limited clinical data support the idea of some kind of defective implantation. Even though the same numbers of good quality embryos were transformed, the implantation rate per embryo (data shown before) and pregnancy rate appeared to be lower among women with moderate to severe endometriosis compared to the controls. The frequency of multiple pregnancies also seemed to be lower. An explanation for the present results is beyond the scope of this study, but may be related to mechanisms related to angiogenesis, the immune system, and/or endometrial receptivity (Bergqvist et al., 1997; Toya et al., 2000). Clinically, ovarian resection is one possible explanation for the present results, but on the other hand, the need for operative treatment also reflects more severe disease. In a study by Tinkanen and Kujansuu (2000) there were 100 women with stage III/IV endometriosis with a history of surgery for ovarian endometriosis or with prevailing ovarian endometriosis. The patients were divided into two groups, 55 women with no ovarian endometriosis and 45 women with recurrent endometrioma. The pregnancy rate was 38% in the endometrioma group and 22% in the group without endometriomas. 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