I was just perscribed Marvelon 28 oral contraceptive and was given the generic version Apri 28?

As with any medicine, side effects are possible with birth control pills (oral contraceptives); however, not everyone who uses birth control pills will experience side effects. In fact, most women tolerate them quite well. If side effects do occur, in most cases, they are minor and either require no treatment or can easily be treated by you or your healthcare provider.
Some of the common birth control pill side effects include but are not limited to:
Acne, although birth control pills can also improve acne
Breast tenderness and enlargement
Breakthrough bleeding and spotting between periods
Nausea and vomiting
Changes in your eyes that make it more difficult to wear contact lenses
Bloating
Headaches
Changes in sex drive (typically a decrease).

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Women are often concerned about weight gain due to birth control pills, but recent research suggests that birth control pills do not cause weight gain for most women.
Birth control pills with a high progesterone component a more likely to cause acne and excessive hair growth (Apri 28 does not have a high progesterone component)
Some birth control pill side effects, while occurring infrequently, are potentially serious and should be reported immediately to your healthcare provider. These include but are not limited to:
Depression or other emotional changes
Migraines
Breast lumps
Heavy vaginal bleeding between periods (light bleeding or spotting is normal)
High blood pressure (hypertension)
High cholesterol
Blood clot in leg, lungs,arm, eye
Stroke