Brief Answer:
Please check if any iron salt is there in the supplement.

Detailed Answer:
Hello and thanks for choosing 'Ask A Doctor' service for your query,

First and the foremost kindly check if your vitamin box contains any salt of Iron (Ferrous ascorbate or ferrous sulfate etc).

Please check the composition with your pharmacist if not mentioned on strip or bottle of tablets.
Iron supplements are the most likely cause of the problem you are mentioning.

So kindly check it and revert back.
Awaiting.

Thank you

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Brief Answer:
Gurgling means gas.

Detailed Answer:
Hello and thanks for follow up,

Colors of stools from grey to yellow to dark brown or black (except tarry black like charcoal) has no significance unless the patient is symptomatic.
Even in case you need to take iron polypeptide complexes(latest) they won't give you gut symptoms.

As for gurgling sound, take Activated charcoal tablets (over the counter) twice daily to absorb excessive gas.

During pregnancy, a number of changes take place with in body ranging from increased blood volume to increased body weight stimulated nerves, etc.

So just don't worry about the color of stools. Even the undigested minerals may impart color to stools.

Hope I was easy to understand,
Follow-ups are welcome.
Have a happy maternal period.
Regards

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