Intrauterine adhesions, or intrauterine synechiae, is a condition in which scar tissue develops within the uterine cavity. Intrauterine adhesions accompanied by symptoms (eg, infertility, amenorrhea) are also referred to as Asherman syndrome [1-3]. The degree of adhesion formation and the impact of the adhesions on the contour of uterine cavity vary greatly. With minimal disease, thin bands of tissue stretch between surfaces of the uterine cavity, whereas severe disease is characterized by complete obliteration of the cavity, with the anterior wall of the uterus densely adherent to the posterior wall. These may impede menstrual flow or interfere with conception or pregnancy.
The diagnosis and management of intrauterine adhesions are reviewed here. General principles of the evaluation of amenorrhea, infertility, or recurrent pregnancy loss are discussed separately. (See "Etiology, diagnosis, and treatment of secondary amenorrhea" and "Evaluation of female infertility" and "Evaluation of couples with recurrent pregnancy loss".)
The true prevalence of intrauterine adhesions is difficult to establish, because the condition is rare in the general population and often asymptomatic. Estimates of the prevalence range from 1.5 percent as an incidental finding at hysterosalpingogram to 21.5 percent of women with a history of postpartum uterine curettage . In a meta-analysis that included over 900 women evaluated with hysteroscopy within 12 months following a spontaneous abortion (86 percent underwent curettage), the prevalence of intrauterine adhesions was 19.1 percent . Even relatively minor surgeries can be complicated by intrauterine adhesions .
ETIOLOGY AND RISK FACTORS
Intrauterine adhesions typically result from intrauterine trauma associated with a surgical procedure, although infection may play a minor contributing role.
Approximately 90 percent of cases of severe intrauterine adhesive disease are related to uterine curettage for pregnancy complications, such as missed or incomplete spontaneous abortion, postpartum hemorrhage, or retained placental remnants [6,7]. There appears to be an increased prevalence of intrauterine adhesions among patients who undergo curettage after a pregnancy loss at a later gestational age compared with early pregnancy . In addition, the risk of adhesion formation appears to be higher in patients that undergo postpartum curettage two to four weeks after delivery compared with early in the postpartum period .