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Molar Pregnancy, Complete or Partial


What is a Molar Pregnancy?

Molar pregnancies are doubly sad for women. Not only do they lose their ‘baby’, depending on the type of molar pregnancy they have, they could be at increased risk of cancer.

With a molar pregnancy, women have all the signs and symptoms of normal pregnancy including nausea, breast tenderness and lack of periods.

The two types of molar pregnancies are:

1. Complete molar pregnancy

2. Partial molar pregnancy

A complete molar pregnancy, clinically known as an Hydatiform Mole, is when the fertilised egg contains only the father’s genetic material and none from the mother. There can be no human growth but instead the placental tissue goes berserk and duplicates itself over and over until the uterus is filled with its grape-like formation.

In a partial molar pregnancy, the egg gets fertilised by two sperm and the resulting embryo is incompatible with life, having 69 chromosomes, instead of the normal 46. Again the placental tissue is abnormal, and continues to grow even though there is every chance the foetus has died.

In very rare cases, there is another type of partial mole pregnancy, where a second normal fertilised egg is produced, but it gets consumed by the crazy growth of the abnormal placental tissue of its twin.

Diagram of an untreated molar pregnancy

The uterus quickly fills up completely with grape-like structured cells

The uterus quickly fills up completely with grape-like structured cells

Signs and Symptoms of a Molar Pregnancy (hydatiform mole)

Doctor may suspect a a molar pregnancy if

  • · the woman’s uterus is large for her gestation period
  • · she has severe vomiting in early pregnancy
  • · she complains of passing of spots of bright red blood
  • · she shows signs, symptoms, and has a positive blood test results for an over-active thyroid gland. (thyrotoxicosis). – Rare.
  • · has no abdominal pain – unless her body is starting to abort the pregnancy

Generally around the 10th week of pregnancy, the woman may experience

  • · bleeding which is dark brown in colour
  • · severe nausea and vomiting
  • · high blood pressure
  • · abdominal cramps

Blood tests will reveal extremely high levels of the pregnancy hormone HCG(human chorionic gonadotrophin)in the case of a complete mole, and lower than normal levels in a partial mole. A uterine ultrasound scan will confirm the diagnosis.

Molar Pregnancy Informational Books

Molar Pregnancy Treatment

An immediate suction and curettage procedure must be carried out under general anaesthetic in a theatre, to rid the body completely of these cells.

It's very difficult to remove ALL of this tissue because it's nature is to embed deeply into the lining of the womb.

If the woman does not plan to have any more children, a complete hysterectomy may be recommended.

Left untreated, hydatiform moles can spread to other organs in the body. In a small percentage of these cases, they can turn cancerous (choriocarcinoma). Early treatment is vital and that includes complete removal of all cells and perhaps follow-up chemotherapy to kill off any remaining cells.

The woman then needs her blood levels of HCG monitored for up to a year afterwards, as high levels indicate that the cells have not been cleared and are still growing somewhere in her body. A woman who still has high levels of HCG in her body six months after the removal procedure is strongly advised to consider hysterectomy at this point, as she is likely to develop choriocarcinoma.

Follow-up observation is vital because even after the uterus is emptied of this tissue, about 20% of women with a complete molar pregnancy will find that the cells have continued to re-grow despite removal, and 2% of those with a partial molar pregnancy.

This is then called persistent gestational trophoblastic disease (GTD).

For this reason, it is strongly advised that women do not become pregnant again until given the all-clear by their doctors.

Ultrasound Scan of a Molar Pregnancy


Causes of Molar Pregnancies

The causes are not fully understood. Either the egg or the sperm may have been faulty, and a school of thought suggest they are caused entirely by a faulty sperm.

However, there does seem to be certain groups at higher risk of suffering one, and those are

  • · Woman from Mexico, S Asia and the Philippines
  • · Women over 40 years of age
  • · Women who have previously suffered from a molar pregnancy
  • · Women who have previously suffered more than one miscarriage

Chances of a future healthy pregnancy

Women who have suffered from a molar pregnancy have only a 1 or 2% chance of having another in the future, and most go on to give birth to healthy children.

The incidence of molar pregnancies in the general population is 1 : 1000, although for an unknown reason this figure is much higher in S Asia, the Philippines and Mexico where the incidence is 1 : 100.

Women who have suffered a molar pregnancy will be in need of grief counselling the same as women who have suffered a miscarriage or stillbirth. They will feel the loss acutely, and have the double blow of finding their health in danger with the risk of either developing cancer or having to have a hysterectomy, thus losing their chances of having children in the future.


Vickie on February 24, 2018:

I had a partial molar pregnancy many years ago and went on to have 3 healthy children. My daughter is pregnant now. I am curious to know if this is hereditary and/or the chances of her having one.

Maureen on October 12, 2011:

Thanks so much! It is always nice to have someone supportive :)

IzzyM (author) from UK on October 11, 2011:

Good luck whatever happens :)

Maueen on October 11, 2011:

Well, I am taking it as a good sign that it only took me 31 days after the D&C to get my regular period back. I'm guessing that either we caught it early enough or maybe it was not a true molar. We will just wait and see.

IzzyM (author) from UK on September 26, 2011:

With the best will in the world, I am not a medical doctor. You must listen to your GP even if it contradicts generally accepted advice. She is the expert here.

But, you know, knowledge is power. This is your decision and not your doctor's or anyone else's. Yours. You do what you think is best for you (in this case). If you'd asked me to go against general medical advice I would say no.

Best of luck :)

Come back and report the outcome :)

Maureen on September 24, 2011:

I'm also confused at why she is telling me tight away to start trying again. She is an amazing doctor and has been through 1 miscarriage, my 2 pregnancies and births with my daughters and now this so I have trouble not trusting her but then again I have not had any blood draws to check my hcg levels since the d&c and all of the sites I read to wait 6 months to a year until ttc again so who knows...

IzzyM (author) from UK on September 14, 2011:

I am so sorry to hear of this. Normally I would say listen to your doctor, but her attitude seems a bit off. If it was me I would wait at least until your hcg levels came back normal twice in a row to be on the safe side. Your children need you to be healthy. Thanks for sharing your story and I sincerely hope next time will be problem-free.

Maureen. on September 13, 2011:

Well I had read about these before, only because when I am pregnant I am an obsessive googler! Well I was pregnant and went in for my 10 week scan and the pregnancy never made it past week 7. I went in for my follow up from my D&C today and was told that the pathology results came back consistant with a partial molar pregnancy but the doctor really feels that she got all of the tissue and it has been about 2 weeks since the procedure and All of my pregnancy symptoms have disappeared. She is waiting on more pathology results before monitoring hcg levels but part of me wants to go get an hpt and see if it comes back positive to give me some idea of what hormones are left. She seems to feel that we got it early enough and that I could start trying to become pregnant again after waiting one cycle. I have had 2 healthy pregnancies, 1 chemical pregnancy between my girls and now this. She seems that I should go on to have a healthy pregnancy though considering that I have had 2 normal pregnancies and she also said "apparently getting pregnant is not an issue for you"

Sun360 on June 11, 2011:

An educative and very informative article which i enjoyed reading from.

IzzyM (author) from UK on May 18, 2011:

You are welcome Sun Girl :) It is very important, I think, for women to know about this.

Sun-Girl from Nigeria on May 18, 2011:

Thank you so very much for educating me on this topic especially by properly highting the two types pf pregnancy.Am so much informed that i can even educate someone else on this topic.Thanks sweety for sharing.Cheers.

IzzyM (author) from UK on March 09, 2011:

I am so sorry to hear about this Cristah. Follow your doctor's advice on this and don't get pregnant again until he gives you the all-clear to do so. You will need follow up tests to make sure all the cells are gone, and it'll take at least a year to know that. I strongly recommend you watch the video above. I'm not an expert on this and don't know about the twin issue, but would think it unlikely as there are always plenty of sperm present but you need to release two eggs to get pregnant with twins, else for the fertilized egg to split in two (giving identical twins).

Christah on March 09, 2011:

I had a molar pregnancy recently. The dr. think it was partial... I lost a liter of blood during my D and C. Very scarry.

So how long do I have to wait to get pregnant again. What needs to be clear? Am I more prone to have twins since mine was partial with 2 sperm? Thanks Christah

IzzyM (author) from UK on December 14, 2010:

Joy, ask your doctor if you have the all-clear to try for another baby, and good luck!

Joy on December 14, 2010:

Women who have suffered from a molar pregnancy have only a 1 or 2% chance of having another in the future, and most go on to give birth to healthy children.

I Thought That You can not live happyly because you cant birth the healthy baby...and thanks for imformative story...im confuces about it...because i experience that h mole preganancy last 2 years ago..i doubt on my self that i cannot birth a healthy baby someday...is soon later..now i want to read any story about it and learn how to this that treament...

IzzyM (author) from UK on August 31, 2010:

Absolutely Subra, and women should be made aware of them just in case it ever happens to them.

subra24 on August 30, 2010:

this is a very important information for those who suffer by molar pregnancy

2uesday on April 27, 2010:

A very informative and well presented hub, well done Izzy. It is nice to know that anyone reading this hub will get accurate and helpful information about this condition.

IzzyM (author) from UK on April 25, 2010:

Thankyou! I hope one day this hub may give hope to someone suffering a molar pregnancy.

itakins from Irl on April 24, 2010:

Extremely informative hub-you sure know your stuff.

IzzyM (author) from UK on April 24, 2010:

Excellent idea. Although statistically women can and do go on to have healthy children, your aunt is living proof!

Faye Constantino from Florida on April 24, 2010:

Yeah, somewhere I have a newsletter. She would send them out in December, but it's been many years now. My sister probably knows as they live in California, and so did our mother's Aunt. I know she had twins, but I think it was two sets, though maybe she had twins and then her kids did. Anyway, just saying, for any that have this problem, it may end up that there are many healthy children in the future!

IzzyM (author) from UK on April 24, 2010:

Oh the poor woman! 12 or 14?? Kids are lovely but hey - that's a bit much - she must have been exhausted running round after all of them!

Faye Constantino from Florida on April 24, 2010:

This is very sad. I have heard of women filled up with tumors and thinking they were pregnant, now I wonder if this is what they were talking about. My mother told me of an aunt who had been excited to be pregnant, only to find out it was a tumor. They told her she would never have children. She went on to have so many that she started a newsletter! (No joke!) She even had twins! I can't remember now if it was twelve or fourteen kids she had.

IzzyM (author) from UK on April 24, 2010:

Thanks Fishtiger :)

I suppose its something most of us wouldn't know about unless we experienced one ourselves.

I didn't, but I knew a woman once it happened to.

fishtiger58 from Momence, Illinois on April 24, 2010:

very interesting I have never heard of this type of pregnancy before.

IzzyM (author) from UK on April 23, 2010:

There is a huge difference and I don't know why. Also the 1 or 2% figure for woman to have a repeat molar pregnancy works out at 1:100 or 1:50 which is relatively high risk compared to the national average. But even though it can be looked on as high risk, it is really low risk when you consider that she has a 98 or 99% chance of having a future healthy pregnancy.

Thanks for the praise :)

rmcrayne from San Antonio Texas on April 23, 2010:

Outstanding hub IzzyM. Glad you added it to your "series" on pregnancy loss. It really does sound shockingly traumatic. Stats are interesting too. Quite a difference between 1:100, and 1:1000.

IzzyM (author) from UK on April 23, 2010:

Thanks Lamme! I'm surprised - I thought everyone had heard of molar pregnancies. Hmmm...maybe I only knew because I studied midwifery??

Lamme on April 23, 2010:

Very informative hub! I'm another one who hadn't heard of this. Thanks for another opportunity to learn!

IzzyM (author) from UK on April 23, 2010:

Well they are rare. 1 : 1000. But aren't they awful? They somehow seem to be much worse than a normal miscarriage. So sad when they occur.

Thanks for commenting, Princessa and Specialk :)

Karen Metz from Michigan on April 23, 2010:

I have never heard of molar pregnancies either! Thanks for educating us.

Wendy Iturrizaga from France on April 23, 2010:

I had never heard of molar pregnancies before. Thank you for such an informative hub, now I know something new!