Blighted ovum: Causes, Signs & Treatment

Blighted ovum: Causes, Signs &Treatment

Miscarriages don’t occur only because of reasons such as hormonal problems or physical problems in the mother. It could also be because of a condition called blighted ovum, which is hard to detect.

What is Blighted Ovum?

A blighted ovum means a condition where a fertilised egg gets implanted in the uterus but does not develop into an embryo. It is also referred as an anembryonic pregnancy. It is a cause of early miscarriage.

During this time, you may not face any signs that the pregnancy is progressing abnormally. Your body will not recognise that there is no baby in the sac because the pregnancy hormones are still being produced.

How Common is a Blighted Ovum?

Blighted ovum occurs so early that you don’t even know you are pregnant. It accounts for about 45% to 55% of all miscarriages. 1 in 2 first trimester miscarriages is due to blighted ovum.

What are the Causes of Blighted Ovum?

The reasons for blighted ovum or causes for anembryonic pregnancy or anembryonic gestation occurring can’t be clearly discerned.
A blighted ovum occurs when the early embryo stops developing, is reabsorbed and leaves an empty gestational sac. The reason this occurs is often unknown, but it could be caused due to chromosomal abnormalities in the fertilised egg. A blighted ovum occurs in early pregnancy between the 8th to the 13th week. Sometimes, even before you know that you are pregnant.

A blighted ovum or anembryonic pregnancy eventually results in miscarriage. Some women wait for it to happen naturally, while others may take medication to trigger the miscarriage. Sometimes, a procedure called dilation and curettage (D&C) is used to remove the placental tissues. Once the miscarriage occurs, your menstrual cycle will resume and you can try for another baby. You may want to wait for a few months to let your body get back to normalcy.

What are the Symptoms of Blighted Ovum?

  • A blighted ovum mostly occurs very early in pregnancy – before most women even realize they are pregnant. You may have the signs and symptoms of a normal pregnancy like nausea and tender breasts. But when the embryo stops growing and the hormone levels decrease, these pregnancy symptoms also subside. There may be abdominal cramping, light spotting or bleeding. However, an ultrasound will show an empty sac.
  • In some cases, women continue to face signs of early pregnancy, as everything appears to be normal. The cause for this is Human chorionic gonadotrophin (hCG) levels which continue to rise and the placenta continues to grow despite blighted ovum. This type of miscarriage is diagnosed by an ultrasound by the 8th week of pregnancy. It will show a large gestational sac, but no embryo.

Symptoms of a blighted ovum

  • Sometimes, the symptoms of a blighted ovum (since the woman s likely unaware of her pregnancy) are mistaken for dysmenorrheal symptoms, because of cramping and minor spotting or bleeding. It ends with the body flushing out the lining of the uterus and you have periods, which may be heavier than usual.

How is Diagnosis of Blighted Ovum Done?

Criteria for diagnosis of a blighted ovum or anembryonic pregnancy through ultrasound are:

  • Failure to identify the embryo in a gestational sac (20 mm) by a transabdominal ultrasound.
  • Failure to identify the embryo in a gestational sac (18 mm) by a transvaginal ultrasound.
  • Failure to identify a yolk sac in a gestational sac (13 mm).
  • There is a possibility that the outline of the sac is irregular or incomplete.
  • An abnormally low position of the gestational sac.

Unfortunately, nothing can be done to prevent a blighted ovum. The gestational sac and accumulated tissues should be pushed out by the end of the 1st trimester. Apart from the natural process, you may use medication to facilitate the expulsion of the content.

If the mother is experiencing symptoms like heavy bleeding or indications of an infection, it is not advisable to wait for a miscarriage. A Dilation and Curettage (D&C) also known as “raspa” is a day procedure which can be used to clear the uterus of the tissue. It must be remembered that doctors normally do not recommend a D&C in cases of early pregnancy loss. A woman’s body is able to pass tissue on its own without an invasive surgical procedure which may cause complications.

Is it Possible to Have a Misdiagnosis?

There may be a chance that there is a misdiagnosis of blighted ovum during early pregnancy. The baby usually starts developing and becomes visible in the transvaginal ultrasound around the 5th or 6th week and around the 6th or 7th week in an abdominal ultrasound.

Tips to avoid blighted ovum misdiagnosis –

  • It may be a good idea to wait for the ultrasound until you are in the 11th or 12th week. An ultrasound may be required earlier if there are any signs of complications.
  • hCG levels are poor indicators of a blighted ovum, hence you should not feel anxious.
  • Most healthcare professionals believe that a natural miscarriage before the 10th week is preferable. However, most misdiagnosed cases are around the 10th week.
  • You can always refer to a new doctor for a second opinion.

What are the Treatments for Blighted Ovum?

In most cases, a blighted ovum needs no treatment, as the body, on recognizing that the embryo is not developing, expels the tissue automatically. However, your doctor will need to take a call on the course of action when the condition is detected, This may include:

  • Medication – Your doctor may prescribe you Misoprostol or Cytotec, which induces a miscarriage. It can be taken orally or inserted into the vagina. Bleeding starts within 2-3 days from taking the medicine. It may cause nausea, diarrhoea or abdominal cramps.
  • Dilation and Curettage (D&C) – This is a surgical procedure to clean out the embryonic tissue. It is done using anaesthesia. The mouth of the cervix is dilated with a surgical instrument and the tissue is either removed by using suction or scrapped out. Though there are no complications in this procedure, there might be some problems like perforation of the uterus, haemorrhage or Asherman syndrome.
  • Natural Expulsion of Tissue – It is always recommended that you wait for the miscarriage to happen naturally. This may take up to two weeks. The benefit of waiting is that there are no chances of complications arising from surgery or medicines.

How is Anembryonic Pregnancy Miscarriage Different From a Missed Miscarriage?

In an anembryonic pregnancy or blighted ovum pregnancy, the sac develops, however, there is no baby inside. This is only detected during a scan. Mostly the embryo was conceived but either it did not develop or was absorbed in the uterus at the initial stage. In most cases a natural miscarriage at home where no embryo is expelled as it has been absorbed or didn’t develop, but pregnancy tissue appears as thick clots. Sometimes, the mother might be advised to undergo a procedure if, waiting for a natural miscarriage to expel the tissue is risky.

While in an an-embryonic pregnancy an embryo is not formed, in a missed miscarriage, the foetus dies during early pregnancy. A missed miscarriage is also known as a silent miscarriage, as the body fails to detect the demise of the foetus and continues to produce pregnancy hormones. The placenta is intact, and the symptoms of pregnancy usually persist. The miscarriage is usually detected by the absence of a foetal heartbeat or by an ultrasound which reveals an underdeveloped foetus during a routine checkup. The embryo can be expelled naturally or via a procedure based on the doctor’s recommendation.

Woman with doctor

Physical Healing After Anembryonic Pregnancy

Physical healing after a miscarriage is different for every woman. Healing could vary depending on if the miscarriage happened naturally, or through a D&C, and how far along were you in the pregnancy.
A woman healing after a miscarriage can continue taking their prenatal vitamins and abstain from sex, douching, and tampons for at least for one month.

Emotional Healing After Anembryonic Pregnancy

Emotional healing from a pregnancy loss can be very difficult, and with a blighted ovum, it is especially important for the woman to realise that she has all the right to acknowledge her loss.

FAQs about Anembryonic Pregnancy

Here are a few frequently asked questions about anembryonic pregnancy;

  1. Will it Affect the Chances of Having Another Baby?

Blighted ovum does not affect the chances of having another baby. As per statistics, women who have had a miscarriage have a high rate of success in their next pregnancy.

  1. When Can You Be Pregnant After Anembryonic Pregnancy?

Doctors will recommend trying again after you have had your first period after the miscarriage. It is quite natural that women are anxious after the miscarriage.

  1. Should You Go with D&C or Wait for a Natural Miscarriage?

A woman can choose to go with D&C or wait for a natural miscarriage. Doctors do not recommend a D&C for early pregnancy. D&C could be beneficial if you plan to get the tissues examined in a pathology laboratory to determine the reason for the miscarriage.

  1. How to Prevent Blighted Ovum?

A blighted ovum cannot be prevented. It usually occurs only once in a woman.

A miscarriage is emotionally draining for any woman, more so in the case of a blighted ovum. Talking about the loss and seeking emotional support from friends and family can go a long way in helping the mother.

Also Read: Chances Of Conceiving After An Abortion