Written by Avvo Staff

Dangerous Drug: Depo-Provera Risks & Lawsuit Information

Depo-Provera, manufactured by pharmaceutical giant Pfizer, is an injected progestin-only reversible contraceptive for women administered every three months. Depo-Provera is highly effective, and initial clinical trials showed failure rates less than one percent, averaging 0.3%. The main ingredient in Depo-Provera is progestogen, and works by preventing fertilization via two ways: 1. Depo-Provera stops the ovaries from releasing eggs and 2. It causes the cervical mucus to thicken thus changing the uterine lining, making it harder for sperm to enter or survive in the uterus.

Adverse Risks

The World Health Organization (WHO) does not recommend the use of Depo-Provera by anyone suffering from deep vein thrombosis, severe migraines, a past history for breast cancer (or current infection), history of stroke, diabetes, and several other threatening conditions. The use of Depo-Provera by anyone with such medical concerns raises their risks for arterial and cardiovascular complications.


Depo-Provera has a two week initiation time before it becomes effective, but only if taken after five days of the start of a period cycle. If taken during the first five days, it becomes effective immediately.

As with many contraceptives and birth control products, Depo-Provera does not protect against, or treat, any sexually transmitted infections.

Delayed fertility is common among users of Depo-Provera. After the last injection, fertility takes around nine months to return.

In 2004, the Food and Drug Administration issued a "black box warning" on Depro-Provera, warning that long term use causes bone loss that may be irreversible.

A study in Thailand found that infants exposed to Depo-Provera had an 80% greater risk of dying within the first year of being born.

The most common side-effects are menstrual irregularities (mainly bleeding), abdominal pain and discomfort, headache, changes in weight, weakness or fatigue, and nervousness.

Depo-Provera Class Action Lawsuit

There is a class action lawsuit, filed in Toronto, against Pfizer on behalf of women who have taken Depro-Provera and developed osteoporosis. The lawsuit claims that Pfizer failed to warn consumers of the real risks evident in research. Pfizer issued a follow-up statement, noting that they are prepared to vigorously defend the lawsuit and emphasized that Depo-Provera is an important option for women and is used safely by millions around the world. The lawsuit continues and has made little progress.

Getting Legal Help

If you or a loved one has suffered serious side effects from Depo-Provera, there is legal help available. Many personal injury lawyers can help determine whether a doctor or drug company, such as Pfizer, can be held liable for damages developed under Depo-Provera.

Before retaining a lawyer, collect as much medical information you can, such as prescription dates, doctor's name and number, dosage, dates injected, etc. Documenting symptoms, the duration of the contraceptive, and any side effects experienced are all important to creating a strong case.

Cases can also be based on damages to a child during pregnancy while the mother used Depo-Provera. Negligent doctors can be found liable for patients who have suffered stillbirths, miscarriages, and/or birth defects. In these cases, patients can often collect damages from doctors for related medical expenses, lost wages, mental anguish, and pain and suffering.

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