Brief Answer:
Pregnancy increases risk of stroke.

Detailed Answer:
I read your question carefully and your concern is completely justified.

Generally speaking every pregnancy increases the risk for stroke in any women, even without a stroke history. In your case since you have a history of stroke already, that risk I am afraid is even higher. That happens due to hormonal and blood pressure changes in your body preparing for the birth.

The risk is higher during the last period of the pregnancy and the first weeks after birth, a time during which the blood coagulability is naturally increased to minimize blood loss during and after birth.

Of course how higher the recurrence risk is in your case, depends on what caused your stroke in first place. I am sure having had a stroke at an abnormally young age, you must have undergone some imaging, cardiac and blood tests to identify the cause.
So some more info on the nature of your stroke (ischemic or hemorrhagic, test results, proposed cause by the doctors might allow for a better prediction of your risk and the management during pregnancy.

I remain at your disposal for further questions (preferably including the additional info I mentioned).

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