Brief Answer:
it might be due to hormonal imbalance

Detailed Answer:
Hello dear, welcome to healthcare magic.I understand your concern.
In my opinion, bleeding and pain abdomen in first trimester of pregnancy suggests abortion. In a few types of abortion like threatened abortion bleeding occurs as warning signal that there is some abnormality but don't worry pregnancy continues normal till term if the cause is corrected and treated accordingly.

The causes of threatened abortion might be thyroid abnormalities like hypothyroidism, progesterone insufficiency , cervical causes and any physical strain.

I suggest you to get ultrasound to know the status of pregnancy and thyroid profile done after discussing with your doctor.

And coming to susten, it is nothing but progesterone hormone. Normally progesterone hormone is very essential for the maintenance of pregnancy. As in progesterone insufficiency, the bleeding might occur, susten is supplemented to counteract that. It does not harm. It is advised even upto 34 weeks in a few cases.

So dont worry. Take adequate rest. Avoid intercourse. Take adequate fluids and iron rich food like green leafy veggies,dates,jaggery,figs and iron supplements to counteract anaemia caused
due to bleeding.
Relax with apt treatment pregnancy continues normally till term.
Hope this satisfies your query.
Feel free to discuss furthur.
Best regards...Dr srilatha

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