Asherman's Syndrome and Miscarriage

Asherman's syndrome, characterized by scarring in the uterus, is a condition most often associated with a common surgical procedure called dilation and curettage (D&C). The D&C may be used to remove excess tissue for any number of reasons, including:

• To resolve abnormal uterine bleeding
• When tissue is abnormally retained as can happen in women with polycystic ovary syndrome (PCOS)
• To remove tissue not totally expelled after a missed miscarriage, incomplete miscarriage, or delivery

Following a D&C, uterine tissues can sometimes stick together abnormally and form adhesions. Fibrosis, the thickening and scarring of connective tissue, is also involved. Depending on the extent and severity of the scarring, Asherman's syndrome may result in miscarriage, infertility, pain caused by trapped blood, and other obstetric complications.

While a D&C is the predominant cause of Asherman's syndrome, other conditions can lead to uterine scarring, including pelvic radiation and the use of intrauterine devices (IUDs).

Asherman's syndrome often causes no symptoms aside from a difficulty in conceiving or maintaining a pregnancy. The formation of adhesions and fibrosis typically reduces blood flow to the uterus. When this happens, some women may have extremely light periods or have no periods (amenorrhea). If blockages develop, they can often cause pain during ovulation or menstruation.

The gold standard for diagnosing Asherman's syndrome is a procedure called a hysteroscopy in which a thin, lighted scope is inserted into the vagina to examine the cervix and uterus. Doctors may also order X-rays, transvaginal ultrasound, and biopsy to evaluate the severity and extent of scarring and to help determine the course of treatment.

The risk of Asherman's syndrome is often associated with the number of D&C procedures a woman undergoes. According to research, the risk of Asherman's increases from 14 percent after one or two D&Cs to 32 percent after three. Other factors can increase the odds of developing Asherman's:

• A D&C following a missed miscarriage (30 percent risk)
• A D&C performed one to four weeks after delivery (25 percent risk)

Scarring and adhesions can prevent a pregnancy by restricting blood flow and nourishment to the developing fetus. As a result, women with uterine adhesions have anywhere from a 40 percent to 80 percent chance of miscarriage and a one in four risk of premature birth. If severe cases, scarring can lead to a potentially serious ectopic pregnancy (tubal pregnancy).

The surgical removal of adhesions can significantly improve the odds of having a successful pregnancy. With that being said, it can be a technically difficult procedure and needs to be performed with care to prevent the formation of additional scars. Hysteroscopy is typically involved. Laparoscopy (commonly referred to as key hole surgery) may also be used in more complicated cases.

After the surgery, some doctors will recommend the placement of an intrauterine balloon to keep tissues from sticking together. Oral estrogen may also be prescribed to help induce the regeneration of uterine tissue and promote healing.