Blighted Ovum: Causes And Symptoms Of Anembryonic Pregnancy

What Is A Blighted Ovum? What Expectant Mamas Should Know

March 29, 2020 Updated August 6, 2020

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One of the first things a person learns when they become pregnant is how nerve-wracking the experience is — especially when new and scary things seem to lurk around every corner. There’s a long list of prenatal tests, tracking pregnancy hormones, ultrasounds, and fear of miscarriage that don’t dissipate for at least the first trimester. That long list also includes a blighted ovum. Although you may never have heard of this prior to your pregnancy, it’s something your obstetrician may discuss with you at some point. And that probably brought you here, in search of more information.

So, the best thing we can do for you is to help you understand this condition and remind you that, should you suffer from a blighted ovum, you don’t have to go through this alone.

What is a blighted ovum?

Per the American Pregnancy Association, a blighted ovum refers to a fertilized egg that attaches itself to the uterine wall but doesn’t develop into an embryo. Cells continue to form the placenta and embryonic sac, but the embryo itself fails to form. Also called an anembryonic pregnancy, this condition typically occurs in the first trimester — often before one even realizes they’re pregnant. It’s not quite clear why blighted ovum occur, but according to the Mayo Clinic it may be due to chromosomal abnormalities in the fertilized egg.

Is a blighted ovum a miscarriage?

Unfortunately, yes, a blighted ovum is a type of miscarriage. Although it often occurs so early that it isn’t noticed, it’s possible to get a positive pregnancy test only to find your results negative upon re-testing a few days later. Let yourself grieve the loss. You forged life in your belly, Mama, and you lost it. Honor the profundity of whatever you’re feeling right now — no matter how long you were pregnant, your emotions are valid.

Is a blighted ovum a chemical pregnancy?

It could be. A chemical pregnancy is used to describe a miscarriage that occurs very early in pregnancy, often by the fifth week when most women may not even know they’re pregnant. If testing early, you might get a positive pregnancy test followed by what may feel like a heavy period. Since some blighted ovums are not diagnosed, they could be described as a chemical pregnancy if they occurred in that early time frame. A chemical pregnancy usually occurs between week four and five of pregnancy, about two weeks after ovulation and fertilization.

What are the symptoms of a blighted ovum?

You may be wondering how you would know if you are having or have had a blighted ovum. Despite it occurring so early in the pregnancy, you may still experience symptoms that could signal a blighted ovum pregnancy. The most obvious of which is a skipped period, which may even prompt you to take a pregnancy test or schedule a visit with your OB-GYN.

If you’re also testing your hCG levels, you may see that they are rising and assume all is well. In fact, you may just feel pregnant. Because your body knows that something has implanted into the uterus, it continues to behave as though that something is a developing embryo. It produces early pregnancy hormones, in turn causing early pregnancy symptoms like nausea and sore breasts.

Since those mixed signals could understandably confuse you, keep an eye out for red flags. These include heavy bleeding (as you would have during your period) and severe cramping, which warrants a trip to the doctor anytime you’re pregnant or suspect to be.

What causes a blighted ovum?

First of all, know this is not your fault. A blighted ovum, which is the cause of around half of first trimester miscarriages, is thought to take place when the body recognizes a high level of chromosome abnormalities. Because your body senses that will not lead to a healthy fetus, it naturally miscarries.

How is a blighted ovum diagnosed?

If you are diagnosed with a blighted ovum, it will usually be because you suspect you’re pregnant. Maybe you just have a gut feeling. Or maybe you took a pregnancy test. Either way, if your doctor does an ultrasound and you have a blighted ovum, they’ll see only an empty gestational sac and no embryo or fetal pole. This would typically take place by around the six-to-eight-week mark.

Since ultrasounds aren’t the norm prior to seven-weeks pregnant due to the size of the embryo, it is possible for a blighted ovum to be misdiagnosed. If you’re earlier in your pregnancy than you think, the absence of an embryo or fetal pole could be interpreted as a blighted ovum since your doctor is under the assumption that you’re at least seven weeks or so along.

Misdiagnoses are rare, though. If the ultrasound doesn’t show an embryo, your doctor will likely ask for a follow-up appointment a few days later — especially if you’re fuzzy on the date of your last period.

How long does it take to miscarry a blighted ovum?

Some women are never diagnosed with a blighted ovum, so they’re unaware that their body is passing the tissue on its own. So, the amount of time a blighted ovum takes varies. The placenta and sac can still grow, continuing to send out those pregnancy signals.

If you get a blight ovum diagnosis from your doctor, you’ll be sent home with instructions to wait it out. Having said that, if your body doesn’t miscarry before your next follow-up appointment (which was probably set for a week or two later), your doctor could recommend other treatment options, such as a procedure referred to as dilation and curettage (D&C) to surgically remove the tissue.

Hold up! What’s a D&C?

It’s possible that your doctor will prescribe a pill to take to help you pass your miscarriage. However, if a D&C is performed, we want you to be prepared. Your doctor may refer to your D&C as a “suction D&C” or a “uterine aspiration.” Depending on multiple factors, you doctor may either scrape or vacuum out the tissue. The procedure can a bit uncomfortable, but women are usually given some form of anesthesia – general or local/regional. It is typically performed in an operating room or right in the doctor’s office and lasts less than five minutes. Most women consider the aftereffects to be the “worst part” of a D&C. Once you head home, you will likely experience cramping for 3-4 days. You may also have spotting that can last for up to two weeks. While most docs may suggest skipping sex for a few weeks, you should be comfortable returning to work within a day or two.

Can you prevent a blighted ovum?

Unfortunately, no, there’s no way to prevent a blighted ovum. However, repeated losses due to blighted ovum would prompt your doctor to refer you for further testing to rule out underlying causes such as genetic mutations or other issues that testing can help detect. Miscarriages are almost never the fault of the mother and if you experienced one it’s important to know this was completely out of your hands.

How common is a blighted ovum?

Unfortunately, a blighted ovum is the most common cause of miscarriage in early pregnancy. In fact, according to the American Pregnancy Association, some experts believe they are the cause of nearly 50 percent of all miscarriages.

Does a blighted ovum affect my chances of a successful pregnancy?

Take heart, Mama. While a blighted ovum is definitely a heartbreaking setback, it doesn’t mean you won’t conceive again. In fact, a blighted ovum is usually a one-time occurrence —most women go on to give birth to a healthy baby within five years. Just remember: Doctors generally suggest you wait at least one to three regular menstrual cycles before trying to get pregnant after any type of miscarriage.