Oct 05, 2026 10 min read

Early Pregnancy

Blighted Ovum: Causes, Symptoms, and What to Expect

Quick Answer: A blighted ovum (anembryonic pregnancy) is when a fertilised egg implants in the uterus but an embryo fails to develop. It's a common cause of first-trimester miscarriage, typically diagnosed via ultrasound showing an empty gestational sac. hCG levels may still rise, causing pregnancy symptoms, but there's no viable embryo.

Ultrasound illustration showing gestational sac

Key Takeaways

A blighted ovum occurs when a fertilised egg implants and a gestational sac forms, but the embryo doesn't develop - it's a random chromosomal event, not something you caused.
Pregnancy symptoms can still occur because hCG is produced by the developing placenta tissue, even without an embryo present.
It's usually diagnosed at the 8-12 week ultrasound when an empty gestational sac is seen with no embryo or heartbeat.
Treatment options include expectant management, medication (misoprostol), or surgical removal (D&C), with similar outcomes for future fertility.
After one blighted ovum, the chance of a successful next pregnancy is approximately 85% or higher.

What Is a Blighted Ovum?

If you've just been told you have a blighted ovum, I know how confusing and devastating that feels. You went in for a scan expecting to see your baby, and instead you got a diagnosis most people have never even heard of. Let me explain what's actually happening - because understanding it won't take away the pain, but it might help you process it.

A blighted ovum (medically known as an anembryonic pregnancy) is one of the most common causes of first-trimester miscarriage. It occurs when a fertilised egg implants into the uterine wall and a gestational sac (the fluid-filled structure that would normally surround the embryo) forms, but the embryo itself fails to develop. The cells that would become the embryo stop dividing very early - usually within the first few weeks of pregnancy.

The term "blighted ovum" is somewhat outdated. The more accurate term is "anembryonic pregnancy," because it wasn't that the ovum (egg) was blighted - rather, the developmental process went awry at a very early stage. But "blighted ovum" is still the term most commonly used and searched for, so I'll use both interchangeably in this article.

Godfrey and Phillips (2004) reported that anembryonic pregnancies account for approximately 50% of all first-trimester miscarriages, making them the single most common type of early pregnancy loss.

What Causes a Blighted Ovum?

The most important thing I want you to hear right now: a blighted ovum is not your fault. It is not caused by anything you did - not the coffee you drank, the exercise you did, the stressful day you had, or the glass of wine before you knew you were pregnant.

Chromosomal Abnormalities

The overwhelming cause of blighted ova is chromosomal errors during fertilisation or early cell division. When a sperm fertilises an egg, the resulting cells need to divide correctly and develop into an embryo. If the chromosomal material is abnormal - too many chromosomes, too few, or structural rearrangements - the embryo cannot develop and growth stops.

Philipp and Kalousek (2002) performed chromosomal analysis on products of conception from anembryonic pregnancies and found that approximately 80-90% had significant chromosomal abnormalities. These are random errors - they are not inherited from either parent and they have no bearing on future pregnancies.

Can a Blighted Ovum Be Prevented?

Unfortunately, because blighted ova are caused by random chromosomal errors during fertilisation, they generally cannot be prevented. Taking folic acid, maintaining a healthy lifestyle, and avoiding known teratogens are sensible preconception steps, but they cannot prevent chromosomal abnormalities from occurring.

Do You Still Have Pregnancy Symptoms with a Blighted Ovum?

Yes - and this is what makes a blighted ovum so confusing and emotionally painful. The gestational sac still produces hCG (human chorionic gonadotropin), which is the hormone responsible for most early pregnancy symptoms. So you may still experience:

Nausea and morning sickness
Breast tenderness and swelling
Fatigue
Increased urination
Food aversions or cravings
A positive pregnancy test

I've heard from women who describe the shock of having textbook pregnancy symptoms - even getting stronger - only to be told at their scan that there's no baby. The disconnect between how you feel physically and what's happening biologically is jarring and deeply distressing.

According to Bourne and Bottomley (2013), hCG levels in blighted ova can continue to rise in the early weeks because the trophoblast (the cells that form the placenta) can develop independently of the embryo. This is why hCG levels alone cannot diagnose a blighted ovum - only ultrasound can confirm the diagnosis.

Will hCG Levels Rise with a Blighted Ovum?

Yes, hCG levels can rise with a blighted ovum, which is one of the reasons this type of miscarriage is so confusing. In a normal pregnancy, hCG doubles approximately every 48-72 hours in the first few weeks. In a blighted ovum:

hCG may rise initially but may be lower than expected for gestational age
hCG may plateau or rise more slowly than in a viable pregnancy
hCG may continue to rise for some time before eventually levelling off or declining

Connolly et al. (2013) found that slower-than-expected hCG rise was associated with non-viable pregnancies, but cautioned that hCG levels alone should not be used to diagnose a blighted ovum. Definitive diagnosis requires ultrasound showing an empty gestational sac.

This is why I typically recommend repeating blood tests and schedule a follow-up scan rather than diagnosing from a single blood draw. The combination of hCG trends and ultrasound findings gives the most reliable picture.

How Is a Blighted Ovum Diagnosed?

A blighted ovum is diagnosed via transvaginal ultrasound. The typical diagnostic criteria include:

A gestational sac is visible (confirming implantation occurred)
The gestational sac measures ≥25mm and no yolk sac or embryo is visible
Or: the gestational sac is visible but follow-up scans over 7-14 days show no embryo development
No cardiac activity is detected at any point

Abdallah et al. (2011) established diagnostic criteria for miscarriage that are widely used: a mean gestational sac diameter of ≥25mm with no visible embryo, or an embryo with a crown-rump length of ≥7mm with no heartbeat, are definitive signs of non-viability.

It's worth noting that if the scan is performed very early (before 7 weeks), it can sometimes be difficult to distinguish between a blighted ovum and a very early but normal pregnancy. This is why follow-up scans are often recommended if there's any uncertainty.

What Happens After Diagnosis?

You have three management options, and I always discuss the best approach with my clients based on your individual situation:

Expectant Management (Watch and Wait)

Your body may eventually recognise the pregnancy isn't viable and pass the tissue naturally. This can take days to several weeks. NICE guidelines suggest that expectant management is reasonable for up to 2 weeks, though some women choose to wait longer.

Chipchase and Johnson (2006) found that approximately 65-80% of women managed expectantly for anembryonic pregnancy completed the miscarriage naturally within 2-6 weeks.

Medical Management (Misoprostol)

Misoprostol (a prostaglandin) causes uterine contractions to expel the gestational sac. It's usually given as a vaginal pessary or oral tablet. Success rates are approximately 80-90% within 3 days (Nielsen et al., 2006).

Side effects include cramping, bleeding, nausea, and diarrhoea. Pain relief should be provided, and having someone with you during the process is recommended.

Surgical Management (D&C)

A dilatation and curettage is a minor surgical procedure to remove the gestational sac. It's quick (15-20 minutes) and usually done under general anaesthetic. It is something I consider if:

Expectant or medical management has been unsuccessful
You prefer not to wait or manage the miscarriage at home
There are signs of infection
You have heavy bleeding

Research by Trinder et al. (2006) found that all three approaches had similar outcomes in terms of completion rates and subsequent fertility, so the choice often comes down to your personal preference and circumstances.

A couple receiving support from their doctor after a blighted ovum diagnosis

Blunted Ovum Success Stories

I know that when you're in the middle of a blighted ovum diagnosis, "success stories" can feel hollow. But I also know that many women find them comforting - not as a guarantee, but as evidence that this experience doesn't define your future.

The statistics are genuinely reassuring:

After one miscarriage (including blighted ovum), the chance of a successful next pregnancy is approximately 85% (Brigham et al., 1999)
A blighted ovum does not indicate any underlying health problem - it was a random chromosomal event
Having one blighted ovum does not significantly increase your risk of having another
Your egg quality, uterine health, and ability to carry a pregnancy are not affected

Many women who've experienced a blighted ovum go on to have healthy pregnancies and babies. The emotional scar takes longer to heal than the physical one, but it does heal - and for most women, the next pregnancy is a joyful one.

How a Blighted Ovum Differs from Other Miscarriage Types

Understanding how a blighted ovum compares to other types of miscarriage can help you process what's happened:

Missed miscarriage: An embryo develops and has a heartbeat at some point, but then stops growing. A blighted ovum is technically a type of missed miscarriage, but specifically one where the embryo never developed at all.
Complete miscarriage: The pregnancy tissue has been fully expelled. You may still experience a blighted ovum that completes naturally.
Ectopic pregnancy: The fertilised egg implants outside the uterus (usually in the fallopian tube). This is a medical emergency. A blighted ovum is always intrauterine - the sac is inside the uterus, which differentiates it from ectopic pregnancy.
Chemical pregnancy: A very early miscarriage (usually before 5 weeks) where the pregnancy test is positive but the pregnancy doesn't progress to the point where a sac is visible on ultrasound.

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If you've been diagnosed with a blighted ovum, I want you to know a few things:

1. This is not your body failing. Your body did exactly what it was supposed to do - it identified a pregnancy that wasn't viable and is (or will) handle it. The chromosomal error happened at a molecular level that no one could have predicted or prevented.

2. There's no right way to feel. Some women feel devastated. Others feel numb. Some feel guilty for not feeling worse. All of these responses are normal.

3. The Miscarriage Association (miscarriageassociation.org.uk) has specific resources for women experiencing anembryonic pregnancy, including a helpline staffed by people who understand what you're going through. I'd also recommend their online forum, where you can connect with others who've had similar experiences.

Trying Again After a Blighted Ovum

When you're ready - and there's no rush - here's what you should know about trying again:

Timing: Most doctors recommend waiting until after your first post-miscarriage period (usually 4-6 weeks) before trying to conceive again. This isn't a medical necessity but helps with dating the next pregnancy accurately.
Fertility: Your fertility is not affected by a blighted ovum. You can ovulate and conceive normally in the cycle following the miscarriage.
Testing: After a single blighted ovum, additional testing is not typically recommended. The cause was almost certainly a random chromosomal error. After two or more consecutive miscarriages, I often recommend karyotyping of both partners.
Emotional readiness: This is just as important as physical readiness. If you feel anxious about trying again - completely normal - consider speaking with a counsellor who specialises in pregnancy loss.

Frequently Asked Questions

Can a blighted ovum be misdiagnosed?

Yes, especially if the scan is performed early (before 7 weeks). If the gestational sac is small or the pregnancy is dated incorrectly, what appears to be a blighted ovum may actually be a very early but viable pregnancy. This is why I always confirm with a follow-up scan 7-14 days later before making a definitive diagnosis.

How long does it take for a blighted ovum to miscarry naturally?

It varies widely. Some women begin bleeding within days of diagnosis; others may wait several weeks. On average, approximately 65-80% of women who choose expectant management will complete the miscarriage within 2-6 weeks.

Can I have a D&C for a blighted ovum?

Yes. A D&C (dilatation and curettage) is a standard management option for blighted ovum. It's quick, done under anaesthetic, and avoids the uncertainty and potential pain of waiting for natural passage. The tissue removed during the D&C can sometimes be sent for chromosomal analysis.

Is a blighted ovum the same as a chemical pregnancy?

No. A chemical pregnancy is a very early miscarriage (usually before 5 weeks) that occurs before a gestational sac is visible on ultrasound. A blighted ovum involves a visible gestational sac but no embryo development. Both are types of early pregnancy loss, but they're different in timing and diagnosis.

Does a blighted ovum mean I have fertility problems?

No. A blighted ovum is a random event that can happen to any woman, regardless of her overall fertility. It does not indicate an underlying reproductive health problem. Most women who experience one go on to have healthy pregnancies.

How common are blighted ova?

Very common. Blighted ova account for approximately 50% of all first-trimester miscarriages. Since approximately 15-20% of recognised pregnancies end in miscarriage, blighted ova affect a significant number of women.

Can the male partner's sperm cause a blighted ovum?

The chromosomal abnormalities that cause blighted ova can originate from either the egg or the sperm, or from errors during the first cell divisions after fertilisation. However, this doesn't indicate a problem with either partner - these are random events during conception.

Cite This Page

Bowen, D. (2026). Blighted Ovum: Causes, Symptoms, and What to Expect. Fertilitys. Retrieved from https://fertilitys.com/blighted-ovum

References

Abdallah, Y., et al. (2011). Gestational sac and embryonic growth are not useful as criteria to define miscarriage. Ultrasound in Obstetrics and Gynecology, 38(3), 279-285.
Bourne, T. and Bottomley, C. (2013). When is a pregnancy non-viable and what criteria should be used to define miscarriage? Best Practice and Research Clinical Obstetrics and Gynaecology, 27(5), 723-737.
Brigham, S.A., et al. (1999). Patterns of miscarriage after first-trimester viability. British Journal of Obstetrics and Gynaecology, 106(3), 275-281.
Chipchase, J. and Johnson, P. (2006). Expectant management of anembryonic pregnancy. BMJ, 332(7552), 1241.
Connolly, A., et al. (2013). Human chorionic gonadotropin for the prediction of pregnancy outcome. Fertility and Sterility, 100(3), S448.
Godfrey, M. and Phillips, J. (2004). Anembryonic pregnancy. eMedicine Obstetrics and Gynecology.
Nielsen, S., et al. (2006). A randomized trial comparing expectant with medical management for first-trimester miscarriages. Human Reproduction, 21(5), 1241-1247.
Philipp, T. and Kalousek, D.K. (2002). Generalized abnormal embryonic development in blighted ovum. Human Reproduction, 17(9), 2330-2337.
Trinder, J., et al. (2006). Management of miscarriage: expectant, medical, or surgical? BMJ, 332(7552), 1235-1240.

Medical Disclaimer: This article is for informational purposes only and does not constitute medical advice. If you have been diagnosed with a blighted ovum or are experiencing symptoms of pregnancy loss, please contact your healthcare provider. If you are experiencing heavy bleeding, severe pain, or signs of infection, seek immediate medical attention.