
Pregnant. Spotting And Abdominal Pain. Ultrasound Showed Second Cystic Sac. Is This Dangerous?

I have my first ultrasound last Tuesday, all fine. I have had another scan today and although baby heart was detected, they have found 'a second cystic sac seen below gestation sac measuring 49x38x28mm'.
The nurse and the midwife advised this could have been a second pregnancy that has not developed and was missed on first scan or a bleed? They have booked me in for another scan in 2 weeks.
I am very concerned and really don't understand that this means. Is this dangerous?
Thank you for writing to us.
From your information, I am guessing you are in your first trimester, as you have mentioned that you recently had your first ultrasound scan. If this is not the case, please do correct me by mentioning your correct obstetric history. I would like to know how many times you have been pregnant, any previous miscarriages, abortions, living children, etc. Thank you for this information, it will be very helpful.
I shall first start by listing all the causes for a brownish discharge seen during pregnancy. They are:
1. Sometimes a few drops of brownish discharge seen during the first trimester is normal. But only this happens once, not repeatedly
2. Miscarriage (first trimester)
3. Ectopic pregnancy (second trimester)
4. Premature separation of the placenta (seen in females with second pregnancy)
Out of the above mentioned causes, number 3 and 4 are ruled out in your case, as the ultrasound returned a normal report.
Now coming to number 2 which in my opinion is the most possible cause. I shall explain this. As number 1 will only have a brown discharge once, and no abdominal pain.
The ultrasound reported the presence of another cystic sac, which means, yours could have been a twin pregnancy. But, one fetus might have not survived. If this second fetus was lost, your symptoms of dull aching pain in the lower abdomen and brown discharge would be completely normal.
I understand this is sad, but all you need to do now is concentrate on staying healthy to take care of the healthy fetus; and to go about the next ultrasound after 2 weeks. In this much time, the healthy fetus would have grown quite a bit, and we can easily visualize this fetus, to check if everything is right, and rejoice.
I hope I have explained this information well enough. Do contact me for any further clarifications. I would be more than happy to help you. Do not worry, I am sure your baby is fine, and will be born healthy and beautiful.
God bless,
Best wishes.


Do not worry. This sometimes happens.
When twin pregnancies take place, it takes some time to detect them. And as one of your fetus is healthy and growing, the second sac could have gone unnoticed or could have been hidden by the larger, healthier and bigger gestational sac.
Yes, your baby should be fine. Do not worry about it. There have been many such cases, and one recently even in my family. My sister-in-law who had a condition called polycystic ovarian syndrome(PCOS) was on medication, which predisposes to twin pregnancies. And in the first trimester, we found a second gestational sac, but the second fetus did not survive. She delivered a healthy, 3.3 kg baby girl, 2 weeks ago.
So please do not worry, stay stress-free and relax. Go for regular check-ups, keep in touch with your doctor and all should be well.
I wish you the best of the best, and a beautiful and healthy baby. God bless. If you have any further clarifications, please write back to me. If not, you could rate my answers after closing this discussion.
Take care.

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