Reproductive Outcome following Hysteroscopic Monopolar Metroplasty: An Analysis of 203 Cases

The first hysteroscopic septum resection was performed in 1974, and the first successful outcome following this procedure was in 1981 (1, 2). Uterine septum is the most common congenital uterine malformation with an incidence of 2-3% (3-5), often causing spontaneous miscarriage (6, 7) or premature delivery in 5 to 25% of cases (8, 9). A septate uterus is also seen in about one-third of women with recurrent miscarriages who are diagnosed with Mullerian anomaly (10). The reproductive history of recurrent miscarriage or fetal loss is considered an important indication for uterine septum treatment (11-13). Alternatively, the effect of a sub-septate uterus on women’s fertility in the absence of a bad obstetric history is still a debatable subject (13). The side effects of abdominal surgery, which include the risk of both pelvic adhesions and cesarean delivery, are reduced with hysteroscopy, thereby it has been recognized as a favorable and safer therapeutic procedure for removal of a uterine septum (1, 11, 14-16). The present study aims to evaluate reproductive outcome following septum resection by hysteroscopy in women with history of infertility or recurrent miscarriage.

The septum was completely removed during the first hysteroscopy in 242 (92%) patients. A residual septum was seen in 21 (8%) patients with required additional intervention. The results of HSG after the second surgery in these 21 patients confirmed that the uterine septum was present in three patients, which were successfully removed after the third surgery. Three cases were complicated by small perforations, but did not need any additional treatment. One operation resulted in bleeding which was controlled by a Foley catheter. There were no cases of postoperative Asherman’s syndrome.

The mean age, body mass index (BMI), mean duration of infertility, other etiology of infertility and the number of patients with histories of assisted reproductive technology (ART) and IUI are shown in table 1. According to the results of HSG, 245 (93.2%) patients had partial septum, whereas 18 (6.8 %) patients had complete septum (Table 1).

Postoperatively, outcomes of 203 out of 263 patients were analyzed, while 60 patients were lost in follow up. Out of 203 patients, there were 80 (39.4%) patients treated with ART, 27 (13.3%) patients treated with IUI, and 96 patients trying to get pregnant, naturally. Pregnancy was achieved in 80 (39.4%) out of 203 patients in the following conditions: 45 (56.2%) naturally, 25 (31.3%) after ART and 10 (12.5%) after IUI. From these patients, 10 (12.5%) pregnancies ended in miscarriages among whom 6 following ART, 1 after IUI and 3 women conceiving spontaneously. Table 2 shows the outcomes of pregnancies as follows: 1 (1.25%) was ectopic, 1 (1.25%) ended in preterm labor, and 68 (85%) resulted in term deliveries.

There were 52 patients with histories of 62 pregnancies (6 patients with history of miscarriage and preterm labor, 2 patients had history of ectopic pregnancy and miscarriage, while one with history of miscarriage, preterm labor and term delivery) resulting to the following conditions: 41 (20.2%) ended in spontaneous miscarriages, 7 (3.4%) were ectopic, 9 (4.4 %) resulted in preterm labor and 5 (2.5%) ended in term delivery. The postoperative outcome in this group resulted in 80 women who became pregnant with the following outcomes: 10 (4.9%) ended in spontaneous miscarriages, one (0.5%) ectopic pregnancy, one preterm labor (0.5%) and 68 (33.5%) with full term deliveries. Postoperatively, rates of miscarriage, preterm labor and ectopic pregnancy reduced as compared to before (p<0.0001, p=0.02, and p=0.07). Term deliveries increased significantly from 2.5% to 33.5% (p<0.0001,Table 3).

In our study population, septum resection by hysteroscopy was followed by an obvious improvement in pregnancy outcome, while the preoperative rates of miscarriage, preterm labor and term delivery in the current study were 20.2, 4.4, and 2.5%, respectively. After hysteroscopic septum resection, the miscarriage and preterm labor rates dropped to 4.9 and 0.5%, respectively, and the term delivery rate increased to 33.5%.

Our results are comparable with the findings of two other reviews of reproductive outcome before and after hysteroscopic septum resection (7, 18). Other researchers have reported postoperative miscarriage rates of 5-20% (14, 19) and term delivery rates of 62.8-87% (2-4, 20). This reproductive outcome improvement following septum resection might be related to an increased volume of uterine cavity, which creates an appropriate location for implantation and enhanced endometrial function via re-vascularization of uterine connective tissue (14, 21).

Hysteroscopic septum resection is a safe and effective procedure for achieving normal uterine shape (4, 22, 23). According to most studies, few complications have been observed in hysteroscopic septum resection (11, 22-24). This procedure is valuable in patients with recurrent miscarriage (23-25). However, there is a question regarding those patients with infertility (13, 26). It seems that a septate uterus is associated with sustaining a pregnancy, not infertility (2, 23); therefore, in patients with infertility, septum resection is performed to prevent miscarriage and preterm labor (22). Some studies have shown that uterine septate may be the cause of secondary infertility (2, 7, 10). In our study, 27 (47.4%) pregnancies in primary infertile patients and 13 (86.7%) pregnancies in secondary infertile patients were natural conception after septum resection, which raises the possibility of a septate uterus as a probable cause for infertility. Similarly, others have noted postoperative pregnancies in about 54% of infertile patients with uterine septum (25, 27). The mechanism of infertility and early pregnancy loss in women with septate uterus has not been ascertained (28, 29). Some investigators attribute this to the insufficient vascularization of the septum fibroelastic tissue and important ultrastructural changes of the septal endometrium during the preovulatory phase in comparison with the lateral wall of the endometrium, which creates a negative effect on implantation (2, 10, 29).

Based on our results, the rate of ectopic pregnancy decreased insignificantly after metroplasty from 3.4 to 0.5%. In one study (13), there was no significant change in ectopic pregnancy before and after septoplasty (2.6% vs. 2.3%). Although the risk for ectopic pregnancy increases in women with utero exposure to diethylstilbestrol (30), there is no study showing the relationship between septate uterus and tubal pregnancy.

Our postoperative miscarriage rate was 4.9% (10/203). Miscarriage was seen in a total of 6 out of 25 (24%) patients conceiving after ART, 3 out of 45 (6.7%) patients conceiving naturally, while 1 out of 10 patients after IUI (12.5%). This has presumably indicated that the reproductive outcome might have been influenced by the method of becoming pregnant as shown by Grimbizis et al. (2).

During the first hysteroscopy, our results indicated lower prevalence of residual septum occurrence (8%) than the results reported by Kormanyos et al. (28) and Porcu et al. (31). However our rates were similar to published works of two other studies (32, 33).

In evaluating the recurrent miscarriage group, 61% tended to get pregnant. All patients conceiving after metroplasty ended in term deliveries. In a study by Venturali et al. (23), about 60% of the recurrent miscarriage group ended in term deliveries; although, the number of patients in this group (n=15) is not large enough to draw a conclusion.

Hysteroscopic septum resection in the patients with infertility and recurrent miscarriage is a safe and effective method, followed by a significant improvement in the reproductive outcome by reducing miscarriage rate and preterm labor and increasing term delivery.