Missed miscarriage (missed abortion) is a silent or delayed miscarriage or early embryonic demise before 20 weeks of gestation. It is called missed miscarriage since there can be a few to no signs, and most women may still feel pregnant after miscarriages. An ultrasound scan may show the pregnancy sac with a nonviable fetus or embryo. Embryonic or fetal demise due to cytogenetic abnormalities (chromosomal abnormalities) is a common cause of early missed abortions before ten weeks of pregnancy. It is impossible to continue the pregnancy if the fetus is not viable. You may need medical or surgical treatment if the products of conception are not expelled naturally (1). Read about the causes, symptoms, diagnosis, treatment, and recovery of missed miscarriages.

How Early Can You Have A Missed Miscarriage?

Missed miscarriages can occur any time after conception before 20 weeks of gestation. There are two types of missed abortion–embryonic (preclinical) abortion or fetal abortion. The embryonic miscarriage is when there is no cardiac activity in the embryo with five centimeters or more crown-rump length. The fetal miscarriage is the absence of cardiac activity in the fetus of 7-20 weeks (10mm or more) (1) (2).

What Causes A Missed Miscarriage?

The causes of missed miscarriages are similar to other types of spontaneous abortion (miscarriage) or early pregnancy failure. They include (3):

Fetal chromosomal abnormalities Blighted ovum or anembryonic gestation Maternal diseases

Placental abnormalities Embryonic abnormalities Uterine abnormalities

What Are The Signs Of A Missed Miscarriage?

A missed miscarriage can be asymptomatic (no signs and symptoms) in most women. This is why many women may not know they had a missed miscarriage until their next ultrasound examination. Pain or tenderness is unusual. Some women may have a brownish vaginal discharge, while some may feel unusual and often notice fading pregnancy symptoms such as nausea and tiredness. However, these changes may go unnoticed in the early weeks of pregnancy. Although amenorrhea (lack of periods) can be present, it is also a pregnancy symptom and cannot be distinguished in the early weeks. The home or urine pregnancy tests can be positive even though the missed miscarriage occurred. You may seek medical care if you experience a lack of pregnancy symptoms (4).

How Is A Missed Abortion Diagnosed?

The physical examination and history are not enough to diagnose missed miscarriage since there are no reliable signs or symptoms. Doctors usually recommend laboratory evaluation and imaging tests to diagnose missed miscarriages (4):

Beta-human chorionic gonadotropin (beta-hCG) levels in the blood are low if the pregnancy is not viable. In a viable pregnancy, beta-hCG hormone levels increase at a predictable rate. Pelvic ultrasound or transvaginal ultrasound can help visualize the nonviable intrauterine pregnancy. In case of miscarriage, there is no heartbeat, and pregnancy size looks smaller than it should be around this stage.

Suppose the hCG levels are above discriminatory levels and no pregnancy is seen on ultrasound; the doctor may look for ectopic pregnancy or early pregnancy loss and plans further interventions. Missed miscarriages are also differentially diagnosed from incomplete miscarriages and threatened miscarriages.

What Is The Treatment For Missed Miscarriage?

Most women with missed miscarriages in the early weeks of gestation may miscarry naturally within a few days. In the past it was common to await the onset of an abortion. Currently the uterus is evacuated soon after the diagnosis because of coagulopathy (reduced fibrinogen), infection or anemia. Medications or surgical treatment are recommended if embryonic tissue and placenta (products of conception) fail to pass through the cervix naturally. Treatment options for missed miscarriages include (3):

Surgical interventions such as suction curettage (vacuum aspiration abortion) or dilatation and curettage (D&C)s. These procedures can be done in an outpatient setting.

Medications such as misoprostol and mifepristone (RU 486) are prescribed to empty the uterus for some women. This is often recommended for women who refuse surgical interventions since medical treatment is limited to clinical trials.

Although waiting and medications can be successful, doctors may recommend surgical procedures because many women may require it due to severe bleeding or retained pregnancy tissues. Rho (D) negative women with Rho (D) positive male partners may receive anti-D immune globulin. However, the risk for Rho (D) alloimmunization is less after a missed miscarriage. This is unnecessary if the father is also Rho (D) negative.

How Soon Can You Recover From A Missed Abortion?

The recovery time may vary for each woman, depending on individual factors. Most women can physically recover within a few weeks or a month after a miscarriage. The menstruation usually returns within four to six weeks after the miscarriage. Emotional recovery can be longer than physical recovery in some cases. Complications are rare after a missed miscarriage. A decrease in fibrinogen levels and bleeding can be seen if the nonviable pregnancy is carried out for more than four weeks. Some may have complications of the uterine evacuation process, such as blood loss or infections, but uterine perforation and synechiae (adhesions) are rare. The recovery can be longer if complications occur (3).

How To Cope With A Missed Miscarriage?

For each woman, grief after a miscarriage can be different and at its own pace. Understanding that most early pregnancy losses occur due to chromosome anomalies can help overcome the grief. You may talk to a counselor for better emotional recovery. You may also seek support from local or online pregnancy loss support groups. Talking with friends, family, and other people who have experienced pregnancy loss can be helpful. Partners can also support each other during difficult times. Couples should also avoid blaming each other for pregnancy loss; instead, give time and space for each other during the tough time.

Missed miscarriage often occurs when the embryo cannot survive due to genetic abnormalities. However, one cannot prevent it. You may seek medical care if you are not experiencing usual pregnancy symptoms. Getting pregnant and having a healthy baby after recovering from a missed miscarriage is possible.

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