If you undergo in vitro fertilization, your doctor typically gives you the hormone progesterone to help create a favorable environment for an embryo to implant and to help support an ongoing pregnancy. Progesterone can be given in several different ways; two common routes are as a vaginal suppository or an intramuscular injection in the hip. Side effects may vary a bit depending on the route of administration.
Most women experience only mild side effects from taking progesterone as part of IVF treatment because they use it for a relatively short time. Progesterone use with IVF is stopped immediately if the pregnancy test is negative. If the pregnancy test is positive, progesterone is continued for the first nine to 12 weeks of pregnancy until the placenta makes enough progesterone by itself to support the pregnancy.
The most common side effects from progesterone are those that mimic premenstrual syndrome. You may experience headaches, bloating, irritability, breast tenderness, sleepiness, depression and mood swings. Because these symptoms can be caused by either an oncoming period or pregnancy, women are encouraged to stay on their post-IVF medications until after the pregnancy test.
Muscle Injection Side Effects
When progesterone is prepared in a liquid form for injection in the muscle, the liquid used to carry the progesterone is an oil. Although progesterone in oil has not been approved for use in IVF by the Food and Drug Administration, some physicians still prefer giving progesterone in this traditional form because it causes higher progesterone levels in the blood than with other methods of giving progesterone. However, many women find these intramuscular injections painful. Some have an allergic reaction to the oil, developing hives, rashes or painful lumps at the site of injection. Women who experience these symptoms should let their doctor know so they can switch to another progesterone treatment.
Vaginal Side Effects
Vaginal progesterone administration has fewer side effects than intramuscular administration, but it also produces lower progesterone levels on blood tests, providing less reassurance to the patient and physician that local uterine progesterone levels are high enough to support the pregnancy. If progesterone is administered as a suppository or vaginal cream, vaginal irritation is a possible side effect. Some women find the creams messy and unpleasant to use. Some women experience yeast infections when using progesterone. Vaginal dryness is another possible side effect of taking progesterone.
Cardiovascular Side Effects
Rarely, patients may experience life-threatening side effects from progesterone use related to the formation of blood clots. If you develop a blood clot, symptoms might include persistent pain in the calf, shortness of breath, acute chest pain or coughing up blood. You also might experience stroke symptoms, such as sudden blindness, sudden headache, vomiting, dizziness with or without fainting, sudden weakness in the limbs or speech problems. Any such symptoms of a possible blood clot or stroke require immediate emergency medical attention.