Intrauterine adhesions: Treatment and prevention

INTRODUCTION — Intrauterine adhesions (IUAs) are bands of fibrous tissue that form in the endometrial cavity, often in response to a uterine procedure. IUAs are often associated with menstrual abnormalities and infertility. IUAs are commonly treated with hysteroscopic resection followed by mechanical or hormonal treatments. Clinical challenges include primary prevention of adhesions, surgical removal, and prevention of recurrent disease.

This topic will discuss the management of IUAs. Related topics on clinical presentation and diagnosis, dilation and curettage, and operative hysteroscopy are discussed separately.

●(See "Intrauterine adhesions: Clinical manifestation and diagnosis".)

●(See "Dilation and curettage".)

●(See "Overview of hysteroscopy".)

In this topic, when discussing study results, we will use the terms "woman/en" or "patient(s)" as they are used in the studies presented. However, we encourage the reader to consider the specific counseling and treatment needs of transgender and gender expansive individuals.

PRIMARY PREVENTION — There are no established approaches to primary prevention of IUAs other than avoidance of intrauterine procedures or infections. For women with miscarriage or unintended pregnancy, medical therapy may be used rather than surgical management at an early gestational age (up to 70 days of gestation for pregnancy termination). Women experiencing a missed abortion also have the option of expectant management. In a trial that randomly assigned 82 women with retained products of conception after spontaneous abortion to observation (expectant management), misoprostol, or curettage, only women in the surgical treatment group (2 women, 7.7 percent) had IUAs at the time of hysteroscopy at six months, although the difference was not statistically significant [1]. Limitations include the small number of trial participants and the reality that some women who elect for noninvasive management will still require a procedure for retained products of conception or heavy bleeding.

The following techniques have been associated with reduced postoperative adhesion formation, but long-term data, particularly for pregnancy and live birth rates, are limited.

●Surgical technique – A joint review of studies by the AAGL and the European Society of Gynaecological Endoscopy (ESGE) reported that the risk of adhesion formation appears to be reduced with [2]:

•Procedures confined to the endometrium compared with those involving the myometrium or opposing surfaces [2].

•Procedures using cold loop lesion removal rather than electrocautery [3-5].

•Procedures with less resection compared with greater resection (eg, polypectomy compared with resection of multiple fibroids) [6] and with hysteroscopic resection rather than blind or ultrasound-guided curettage [7-10].

However, less invasive or cold techniques may not be appropriate to treat the underlying pathology (eg, electrosurgery may be necessary for safe removal of a vascular lesion such as leiomyoma).

●Semisolid (gel) adhesion barriers – The above joint review of studies by the AAGL and the ESGE concluded that use of gel adhesions barriers after surgery that could potentially damage the endometrium reduced the development of IUAs in the short term, but available data on subsequent fertility were lacking. The practice guideline did not indicate whether or not gel barriers should be used as a primary prevention strategy. Since the above AAGL review, additional information has come out in support of gel adhesion barriers for primary prevention of adhesions. For example, in a trial comparing the efficacy of hyaluronic acid with no treatment for adhesion prevention after suction dilation and curettage for miscarriage, the women treated with gel had a nearly 60 percent reduction in risk of adhesion reformation (IUA reformation in 13 versus nearly 31 percent, respectively) [11].

At this time, we do not use gel barriers as prophylaxis against adhesion formation for women undergoing routine uterine procedures. However, for procedures that are at high risk of causing adhesion formation, such as suction curettage for retained products of conception or for hysteroscopic myomectomy of opposing fibroids, we discuss the available data with the patient and perform joint decision making regarding the use of gel barriers.

Postoperative measures after resection of IUAs are discussed below. (See 'Prevention of adhesion reformation' below.)

ROLE OF EXPECTANT MANAGEMENT — While surgery is considered the standard of care for symptomatic IUAs, there are no data from trials comparing surgery with expectant management [2]. For women with known symptomatic IUAs who do not want or are unable to access hysteroscopic resection, expectant management is a reasonable option. One study reported pregnancy in 45.5 percent of women who elected expectant management when followed for up to seven years [12].

HYSTEROSCOPIC RESECTION — The standard treatment of symptomatic IUAs is lysis under direct hysteroscopic visualization [2]. Blind dilation and curettage or blind cervical probing, common modes of treatment prior to the development of hysteroscopy, are no longer advised because they do not remove abnormal tissue, disease classification is not possible, and indiscriminate curettage may further damage the endometrium [2].

The goal of surgery is to restore the size and shape of the uterine cavity, as well as endometrial function and fertility [13]. Lysis of moderate or severe adhesions should be performed by an experienced hysteroscopic surgeon. General principles of hysteroscopy are discussed separately. (See "Overview of hysteroscopy".)

●Cervical dilation and hysteroscope insertion – Care must be taken during cervical dilation in women with severe occlusion of the uterine cavity because it is easy to create a false cervical passage and to perforate the uterus. Guidance with pelvic ultrasonography can help define the cervical canal and the junction between the cervical internal os and the intrauterine cavity. Ultrasonography can also be used to guide dissection. Some clinicians may additionally use a guidewire inserted with ultrasound guidance followed by dilation with a balloon when cervical navigation is complex [14]. A small (5 mm) rigid hysteroscope can be used to pass through the cervical canal and into the uterine cavity under direct visualization to decrease the chance for creation of a false passage. We use a 0- or 12-degree hysteroscope for this dissection.

●Excision of adhesions – The procedure is begun by placing the hysteroscope at the internal os and lysing adhesions with sharp dissection. Adhesive bands are identified through the hysteroscope, and clipped at the junction of the band to the endometrium in order to excise the adhesion (in contrast, uterine septa are managed by incision). We prefer to use small, rigid scissors because scissors avoid the thermal tissue injury that occurs with electrosurgery. Careful dissection is continued until the entire uterine cavity is free of adhesions. The goal is restoration of normal anatomy. Alternatives to scissors include blunt adhesiolysis [15] and bipolar electrosurgery, in which the adhesive bands are vaporized [16].

●Adjunctive interventions – For cases that require more extensive dissection, such as when there is agglutination of the walls of the cavity, we suggest concurrent laparoscopy or ultrasound guidance to reduce the risk of uterine perforation [17]. Alternatively, fluoroscopy can be used in severe cases to guide dissection [18]. A cohort study of 770 adhesiolysis procedures performed under fluoroscopic guidance reported an 80 percent primary procedure success rate [19]. Trials comparing fluoroscopically-guided procedures with ultrasound-guided outcomes have not been performed. While there are no data reporting a lower risk of perforation or improved outcome with adjunctive procedures, the rationale is that the use of such approaches may lessen the impact of perforation should it occur [2]. In our practice, we typically utilize ultrasound and find that laparoscopy rarely needs to be performed concomitantly with ultrasound guidance. Avoidance of laparoscopy reduces the surgical risk and speeds recovery from the procedure. However, if perforation is suspected or confirmed when energy is being used for the dissection, then laparoscopy is necessary to exclude an inadvertent bowel injury. If perforation occurs using instruments without energy, expectant management is reasonable.

●Role of laparotomy – If adhesions are so severe that the cavity cannot be entered with the hysteroscope, a laparotomy with hysterotomy is possible, but is rarely performed, and is reserved for severe cases in which no other treatment options are available or possible [2].

Each adhesiolysis procedure is unique and requires a careful understanding of uterine anatomy, and patient, skilled dissection. With a completely obliterated cavity, dissection beginning in the midline and moving laterally under ultrasound guidance may be effective. If there is any area of less dense adhesions that would allow visualization of normal anatomic structures (such as the uterine cornua), dissection should begin in this area. Identification of the tubal ostia, either prior to or during the lysis procedure, can provide useful markers of the lateral and fundal cavity edges, and can be used to guide the degree of tissue removal. Aggressive dissection that might enter the myometrium should be avoided.

PREVENTION OF ADHESION REFORMATION — The goal of post-lysis management is to reduce the risk of reformation of adhesions and promote regrowth of endometrium. However, optimal postoperative management is not known [20-22]. In a meta-analysis of trials comparing multiple types of anti-adhesion therapies, including IUDs, hyaluronic acid gel, hormonal therapy, or human amniotic membrane grafting, with placebo or no intervention, the authors concluded that "clinical effectiveness of anti-adhesion treatment for improving key reproductive outcomes or for decreasing IUAs following operative hysteroscopy in subfertile women remains uncertain" [21]. In the meta-analysis, there was no difference between treatment and no treatment/placebo on live birth rate (odds ratio [OR] 0.99, 95% CI 0.46-2.13, three studies, 150 women), although antiadhesion therapy was associated with fewer recurrent IUAs at the time of second-look hysteroscopy (OR 0.36, 95% CI 0.20-0.64, seven studies, 528 women). Of note, in women surgically treated for IUAs, adhesion recurrence rates of 30 to 66 percent have been reported [2,19].

Our approach — As the optimal methods to prevent adhesion reformation are not known, our management is based upon personal experience in addition to the available evidence (mainly observational studies) [20-22]. Our preferred approach to prevent formation of new adhesions is to treat the woman with estrogen for 30 days following the initial resection, with 10 days of progestin treatment added on days 21 to 30, and place a pediatric bladder catheter in the intrauterine cavity. For women with severe IUAs at the time of resection, we repeat hysteroscopy following the withdrawal bleed. This approach limits the number of required procedures yet still allows for treatment of any new adhesions while they are filmy and easily removed.

●Combined estrogen-progestin hormonal therapy – In our practice, we give 4 mg estradiol orally, twice daily, for 30 days. On the last 10 days of estrogen therapy, we add 5 mg of oral medroxyprogesterone acetate or 2.5 mg of oral norethindrone acetate to the regimen to stimulate a withdrawal bleed.

We use postoperative estrogen therapy rather than no hormonal therapy. For women with no contraindications to estrogen use, the risks associated with this therapy are low and observational data suggest better outcomes with estrogen therapy than with no postoperative therapy. This can be used in combination with a mechanical barrier. When used, estrogen therapy can be started on the day after the procedure. Choice of estrogen and progestin medications is in part driven by multiple factors including practice patterns and insurance coverage. (See 'Estrogen therapy' below.)

●Intrauterine catheter – We use an intrauterine pediatric bladder catheter (ie, pediatric Foley bladder catheter), in addition to estrogen therapy, to provide mechanical separation of the uterine walls during the healing phase. While triangular (eg, Cook) and procedure-specific catheters are available for this purpose, we prefer a pediatric bladder catheter, which can be inserted with minimal cervical dilation and without anesthesia. The catheter balloon is typically filled with 2 to 3 mL of saline. The catheter is removed after 7 to 10 days of use. With either the bladder or Cook catheter, we give antibiotics (ie, doxycycline 100 mg twice daily for 10 days) because the catheter is a foreign body in the uterus that is contiguous with the nonsterile vagina. (See 'Intrauterine catheter' below.)

●Repeat hysteroscopy – For patients with severe IUAs at the time of resection, we perform repeat hysteroscopy in addition to using oral estrogen and an intrauterine catheter. We perform the hysteroscopy shortly (days) after the withdrawal bleed that is induced by the estrogen-progestin treatment. The goal is to remove any newly developed adhesions in women who have already demonstrated the ability to create significant adhesive disease. (See 'Repeat hysteroscopy' below.)

Supporting data on treatment options

Estrogen therapy — The rationale for postoperative estrogen therapy is that the hormone will promote regrowth of the endometrium over the denuded surface. However, there are no evidence-based recommendations on optimal formulation, or duration, in part because studies that compare different estrogen regimens, in isolation from other therapies for IUA prevention, are lacking. We use estrogen therapy in conjunction with repeat hysteroscopy. (See 'Our approach' above.)

Examples of the conflicting evidence include:

●Reviews and meta-analyses – A systematic review of 26 studies reported that estrogen therapy in combination with other therapies (eg, intrauterine device [IUD], bladder catheter) appeared to be beneficial, but the range of results was wide, and meta-analysis was not performed because of the variations in study designs [23]. A different meta-analysis was unable to make any conclusions regarding postoperative estrogen use because of the treatment combinations [22]. A third meta-analysis comparing estrogen with placebo for adhesion prevention after septoplasty found no benefit [20]. However, the studies included were underpowered, as the sample sizes were small and the adhesion formation rate was low among all groups. Lastly, a fourth meta-analysis that assessed the impact of estrogen versus placebo reported there was no difference between the groups in ongoing pregnancy rate [21].

●Randomized trials – Outcomes of trial data vary based on comparator (placebo versus different estrogen doses). Definitive conclusions are limited based on the small numbers of trials, small numbers of included patients, short-term follow-up data, and varying doses of estrogen.

•No benefit – A trial including 182 patients with mild (91) or severe (89) intrauterine adhesions reported similar rates of postoperative adhesion reformation, adhesion scores, and menstrual pattern improvement for those treated with postoperative estrogen compared with no estrogen (all patients were treated with a postoperative intrauterine catheter and five days of oral antibiotics) [24]. Patients treated with estrogen received estradiol 4 mg daily with added cyclic dydrogesterone 10 mg (daily for 7 days on cycle days 21 through 28) for a total of three cycles. Repeat hysteroscopy was performed at 4 and 8 weeks after initial adhesiolysis surgery.

•Unclear benefit – In a trial of 121 patients with Asherman syndrome, similar adhesion recurrence occurred in patients treated postoperatively after adhesiolysis with either 2 or 6 mg of oral estradiol supplementation [25]. Due to a lack of a no-estrogen control group, this study did not address the fundamental question of whether estrogen adjuvant therapy prevents the recurrence of intrauterine adhesions.

●Retrospective cohort – A retrospective cohort study comparing supplementation with oral estradiol 4 versus 10 mg reported no difference in pregnancy rates or adhesion recurrence at second-look hysteroscopy [26].

Intrauterine catheter — Catheters (eg, size 8 pediatric bladder catheter with a 5 cc balloon or Cook catheter) can be inserted into the uterine cavity immediately after adhesion lysis. In our practice, we use a pediatric bladder catheter continuously; this barrier method is well tolerated in our patient population. When a bladder or Cook triangular catheter is used, the device is removed from the uterus after 7 to 10 days [27,28]. When a bladder catheter is inserted, the tubing can be trimmed so it does not hang out of the vagina. (See 'Our approach' above.)

●Continuous use – One study of 110 women who received either a postoperative bladder catheter or IUD after adhesion lysis reported higher rates of normal menses and conception as well as lower reoperation rates for women with catheters compared with women with IUDs [27].

●Intermittent use – A single-blind trial of 191 individuals with moderate to severe IUAs compared catheter placement with brief balloon distention at two and six weeks after hysteroscopic lysis of adhesions with postoperative catheter placement alone [29]. The adhesion reformation rate was lower in the intermittent balloon distention group (20.2 versus 40.2 percent, respectively).

Repeat hysteroscopy — Repeat hysteroscopy can assess for adhesion recurrence, and allow for repeat adhesion resection if reformation has occurred. Such second-look hysteroscopy is commonly performed up to three months after initial adhesiolysis, although the use of serial hysteroscopic procedures at shorter time intervals has also been described [2,30-32].

The technique for serial hysteroscopy is to repeat office hysteroscopy 7 to 14 days after the initial sharp lysis of adhesions. At this time, filmy adhesions that have reformed are bluntly lysed with the hysteroscope, which prevents development of dense adhesions. Typically two to three postoperative office hysteroscopies are required when using this approach. These office procedures are typically well tolerated by the patients. One small study using this technique had the patient return every one to three weeks to repeat the procedure until no further reformation of adhesions occurred [15]. The study reported 92 percent (22/24) of patients had improvement in the staging of their adhesions, 95 percent (18/19) of patients presenting with menstrual flow abnormalities had resumption of normal menses, and 46 percent (7/15) of women who desired pregnancy had conceived or delivered at the time the study concluded. Another study in women with severe adhesions randomized one group to repeat hysteroscopy one week later followed by a subsequent third-look hysteroscopy (n = 36) versus second-look hysteroscopy two months after the initial procedure (n = 35) [33]. Both groups received an IUD and estrogen therapy after the initial adhesiolysis. The group that underwent short-interval hysteroscopy had significantly fewer adhesions at the third hysteroscopy compared with the longer-interval group (11 versus 83 percent). Although the pregnancy rates were not significantly different (47 versus 30 percent), there was a trend for higher pregnancy rate in the group with an early repeat hysteroscopy.

Intrauterine applications — Both hyaluronic acid gel and polyethylene oxide-sodium carboxymethylcellulose gel have appeared to reduce the reformation of IUAs, but their impact on subsequent pregnancy and live birth rates is not known [2,20,22]. One randomized trial (n = 92) comparing postoperative hyaluronic acid gel with no treatment after hysteroscopic adhesiolysis reported a lower rate of adhesions at three-month second-look hysteroscopy (14 versus 32 percent); no long-term follow-up data regarding menstrual symptoms or fertility were reported [34]. While one meta-analysis concluded that gel barriers (hyaluronic acid and polyethylene oxide-sodium carboxymethylcellulose gels) have a role in preventing IUA reformation, a different meta-analysis reported that no definitive conclusion could be made regarding impact because of the heterogeneity of study designs and lack of reproducibility of study results by one research group [20]. Of note, limited data analysis suggested fewer adhesions after use of either agent.

Alternately, investigators have reviewed the use of oxidized, regenerated cellulose adhesion barrier (Interceed) in combination with an IUD. In a retrospective cohort study of 76 women with moderate to severe Asherman's syndrome, significantly more women achieved adhesion-free cavities when Interceed was used in combination with a levonorgestrel IUD compared with an IUD only [35]. In a meta-analysis of 20 studies, including 1891 cases of IUAs, an auto-cross-linked hyaluronic acid membrane and intrauterine amnion grafts were the most effective at reducing the recurrence of severe adhesions [36].

No further treatment — Another option after adhesiolysis is expectant management. Two small studies that evaluated women after adhesiolysis with no postoperative treatment reported inconsistent results. Some women underwent two to three procedures, and the postoperative pregnancy rate was 42 of 47 women in one study [37] but only 9 of 24 in the other [38]. The amount of adhesions at the primary hysteroscopy is a critical factor in determining the recommendation for second look hysteroscopy.

Antibiotic therapy — Of note, there are no data to advise for or against antibiotic use in the pre-, intra-, or postoperative periods, and we do not routinely treat with antibiotics [2] unless a catheter is left in place. (See 'Our approach' above.)

Therapies in development — Medications that improve endometrial vascular flow, intrauterine amnion grafts, and stem cell therapy are potential treatments for adhesion prevention [39]. Case reports have also described successful pregnancies after the infusion of intrauterine platelet-rich plasma [40]. However, data are very limited, and these treatments are only offered as part of research protocols [2,41]. While preliminary studies have suggested that endometrial treatment with platelet-rich plasma may reduce pro-inflammatory gene expression in endometrial cells and improve endometrial proliferation in vitro [42], data are insufficient to advise use of this therapy [43,44].

FOLLOW-UP — We typically see the patient three weeks after primary surgery and perform an ultrasound to assess endometrial development and pattern (eg, does the endometrium extend to each cornua) at that time.

Two to three months postoperatively, we perform hysteroscopy to assess whether a normal contour has been restored to the uterine cavity [2]. If significant adhesive disease is identified, reoperation can be required. However, the size of the uterine cavity is not a clinically significant measure, since it does not correlate well with the ability to conceive and carry a pregnancy [45].

OUTCOME — The data regarding treatment outcomes for IUAs are from small observational studies. The study design and results are inconsistent, and high-quality data are needed.

If myometrial adhesions are present, then the endometrial basalis layer may not facilitate the proliferation of the functionalis layer and allow regrowth of normal endometrium after adhesiolysis [46]. In this case, recurrence of adhesions is likely and functionality diminished, especially if this is true for the majority of the surface of the uterine cavity.

Menstrual abnormalities — Studies have reported a wide range of efficacy of treatment for women with menstrual abnormalities, from 23 to 100 percent. In a systematic review of 28 studies, most studies reported that approximately 80 to 100 percent of women had an improvement in menstrual flow [23].

Infertility — Data are inconsistent about the efficacy of treatment of IUAs in women with infertility. In a systematic review of 28 studies, most studies reported a pregnancy rate of 40 to 80 percent and a live birth rate of 30 to 70 percent [23]. In women with Asherman syndrome who become pregnant following hysteroscopic adhesiolysis, morbidly adherent placenta, including placenta accreta, occurs in approximately 10 percent of cases [30].

The systematic review did not report outcomes separately for women with recurrent pregnancy loss. One study reported all 40 patients who presented with recurrent pregnancy loss were able to conceive after surgical treatment of their adhesions [47]. Another study evaluating reproductive outcomes after hysteroscopic adhesiolysis found that out 8 out of 13 women with recurrent pregnancy loss went on to conceive [48].

Recurrence — The recurrence rate following treatment is as high as 33 percent in women with mild to moderate IUAs and 66 percent in women with severe adhesions [2].

If adhesions recur, a second or third procedure may be necessary to complete the dissection or a second look to lyse any reformed filmy adhesions may be appropriate. The skill of the surgeon and the extent of disease and dissection will determine which option is preferred.

Obstetric outcomes — The likelihood of pregnancy following adhesiolysis appears to vary directly with the severity of disease. In a retrospective study of 357 women who underwent hysteroscopic adhesion resection and were followed for a mean of 27±9 months, the pregnancy rates after adhesiolysis were 61 percent (mild disease), 53 percent (moderate disease), and 25 percent (severe disease) [49]. In this study, the mean time to conception was 9.7±3.7 months, the miscarriage rate was 9.4 percent, and the overall live birth rate was 86 percent. A second retrospective study of 154 women reported similar findings with a live birth rate of 64 percent for the entire cohort of women with Asherman's syndrome after adhesiolysis [50].

Pregnancies in women with a history of moderate to severe IUAs can be considered high risk and may require a consultation from a maternal-fetal medicine specialist. Pregnancy complications can include intrauterine growth restriction, preterm delivery, and abnormal placentation (ie, accreta) [51]. Case studies have reported an approximately 13 to 18 percent incidence of placenta accreta in women treated surgically for IUAs [50,52]. In the above retrospective review, 8 percent of women had a postpartum hemorrhage, of which 4.3 percent were attributed to abnormally adherent placenta and 2 percent were attributed to placenta accreta [49]. Women with a history of surgery for IUAs are assessed during pregnancy for abnormal placentation. (See "Placenta accreta spectrum: Clinical features, diagnosis, and potential consequences".)

SUMMARY AND RECOMMENDATIONS

●Adhesion prevention – There are no established approaches to primary prevention of intrauterine adhesions (IUAs). Minimally traumatic surgical techniques and semisolid (gel) adhesion barriers have been associated with reduced postoperative adhesion formation, but long-term data, particularly for pregnancy and live birth rates, are limited. (See 'Primary prevention' above.)

●Surgical excision compared with expectant management – While surgery is considered the standard of care for symptomatic IUAs, there are no trial data comparing surgery with expectant management. For women with known symptomatic IUAs who do not want or are unable to access hysteroscopic resection, expectant management is a reasonable option. (See 'Role of expectant management' above.)

●Hysteroscopic resection – We perform hysteroscopic resection of symptomatic adhesions. (See 'Hysteroscopic resection' above.)

●Prevention of postoperative adhesions – As the optimal methods to prevent adhesion reformation are not known, our management is based upon personal experience in addition to the available evidence (mainly observational studies). To prevent the reformation of adhesions after hysteroscopic lysis, we insert a pediatric bladder catheter into the uterine cavity postoperatively and then start the woman on oral estrogen therapy, with timed progestin therapy added to induce a withdrawal bleed. We also perform repeat hysteroscopy for women with severe IUAs noted at the time of resection. (See 'Our approach' above.)

•Intrauterine catheter – For women undergoing hysteroscopic adhesion resection, we suggest postoperative insertion of a catheter into the intrauterine cavity rather than no catheter (Grade 2C). Compared with insertion of an intrauterine device or gel, intrauterine catheters have been associated with higher pregnancy rates and lower rates of adhesion reformation. (See 'Intrauterine catheter' above.)

•Estrogen therapy – For women undergoing hysteroscopic adhesion resection, we suggest postoperative estrogen therapy rather than no treatment (Grade 2C). For women with no contraindications to estrogen use, the risks associated with this therapy are low and the body of evidence leans toward better outcomes with estrogen therapy than with no postoperative therapy, although the available data conflict. (See 'Estrogen therapy' above.)

•Repeat hysteroscopy – For women undergoing hysteroscopic resection of severe IUAs, we also suggest repeat hysteroscopy rather than no hysteroscopy or instillation of hyaluronic acid gel (Grade 2C). Timing of this hysteroscopy could be as soon as one to two weeks after surgery or up to one to two months. However, as the optimal approach to the prevention of IUAs is not yet known, these treatment options are reasonable alternatives. (See 'Repeat hysteroscopy' above.)

●Obstetric implications – Pregnancies in women with a history of moderate to severe IUAs can be considered high risk and may require a consultation from a maternal fetal medicine specialist. Pregnancy complications can include intrauterine growth restriction, preterm delivery, and abnormal placentation (ie, accreta). (See 'Follow-up' above.)

●Outcomes after adhesion resection – Outcome data following resection of IUAs are from small studies and thus wide ranges have been reported. Studies of treated women have reported improved menstrual flow in 80 to 100 percent of women, pregnancy rates of 40 to 80 percent, and live birth rates of 30 to 70 percent. However, recurrence rates of 33 to 66 percent have also been noted. (See 'Outcome' above.)