A blighted ovum, also known as an anembryonic pregnancy, is an early pregnancy loss. It occurs when a fertilized egg implants in the uterus, and the gestational sac and placenta begin to form, but an embryo fails to develop or stops developing very early. The body continues to produce pregnancy hormones, leading to positive pregnancy tests and early pregnancy symptoms, despite the absence of an embryo. This condition is a common cause of first-trimester miscarriage.
What is a Blighted Ovum
A blighted ovum results from chromosomal abnormalities in the fertilized egg, which prevent proper embryo development. These genetic errors typically occur randomly during fertilization, meaning they are not caused by anything the parents did or did not do. Although an embryo does not form, the gestational sac and placenta continue to grow. The body often recognizes this developmental issue, leading to the eventual cessation of the pregnancy.
Symptoms and How It’s Diagnosed
Many individuals initially report typical pregnancy signs, such as a missed period or positive pregnancy test. This is because the developing placenta produces pregnancy hormones, like human chorionic gonadotropin (hCG), causing symptoms such as breast tenderness, nausea, and bloating. However, as the pregnancy does not progress, these symptoms may eventually diminish. Later signs include vaginal bleeding, ranging from spotting to heavier bleeding, and abdominal cramping.
Diagnosis is primarily confirmed through a transvaginal ultrasound, typically performed between seven and nine weeks of pregnancy. The ultrasound reveals an empty gestational sac without a visible embryo, or a sac larger than expected for gestational age without an embryo or yolk sac. Blood tests monitoring hCG levels may also be used; if levels do not rise as expected or begin to fall, it suggests a blighted ovum.
When a Blighted Ovum Passes Naturally
A blighted ovum can pass naturally from the body, similar to a spontaneous miscarriage. This process involves the uterus expelling pregnancy tissue, typically manifesting as cramping and bleeding. The timeline for natural passing can vary considerably, ranging from a few days to several weeks after diagnosis. Some miscarriages occur within days of a positive test, while others may take up to 7-12 weeks for the body to recognize the absence of an embryo.
During a natural miscarriage, expect vaginal bleeding heavier than a typical menstrual period, often with blood clots and tissue. Cramping can range from mild to moderate and may last up to a week. Monitor symptoms closely. Seek immediate medical attention if bleeding becomes excessively heavy (soaking more than two pads per hour for two consecutive hours), or if severe pain, fever, or signs of infection develop.
Medical Management Options
When a blighted ovum is diagnosed, several medical management options are available if natural passing does not occur or if preferred. One approach uses medication, such as misoprostol, to induce miscarriage. This medication causes uterine contractions, leading to cramping and bleeding, expelling pregnancy tissues within hours. Side effects can include abdominal pain, fever, nausea, and diarrhea.
Another option is a surgical procedure called dilation and curettage, commonly known as a D&C. This minor procedure involves dilating the cervix and gently removing the contents of the uterus using specialized medical tools and suction. A D&C may be recommended if the body does not naturally pass the tissue, if complications arise, or if a quicker resolution is preferred. The choice of management is personal, made in consultation with a healthcare provider.
Coping and Recovery
Physical recovery after a blighted ovum typically involves some bleeding and cramping. Bleeding can last one to two weeks, while cramping usually subsides within a week. Most individuals can expect their menstrual period to return within four to six weeks. It is generally safe to resume normal activities when feeling well enough, though heavy exercise might increase bleeding.
Beyond physical recovery, the emotional impact can be significant. Experiencing any pregnancy loss, even one where an embryo did not fully develop, can evoke sadness, confusion, or grief. Acknowledge these feelings and allow for emotional healing. Seeking support from partners, family, friends, support groups, or professional counseling can be beneficial. A blighted ovum is typically a one-time event and generally does not affect future successful pregnancies.