Progesterone-only contraceptives come in forms of progesterone-only pills (mini pill), tri-monthly injections, hormone containing IUCD (intrauterine contraceptive device) and emergency pill. These contraceptives have a higher failure rate than other contraceptives in young, healthy, sexually active women. Though no exact number can be used, on average, studies put it that up to 8-9 in every 100 women are at risk of getting pregnant with progesterone only pills compared to 1-2 in every 100 for combined pills and less than 1 with IUCD.
Progesterone only contraceptives are, in an ideal world, recommended for people who want to use hormonal contraceptives but have risk factors that make it undesirable for them to be on estrogen containing contraceptives. These include;
- Breastfeeding mothers – Six weeks after delivery, any woman who is planning to be sexually active should start on their contraceptive of choice. (Women should technically not be sexually active before six weeks so as to heal, allow hormones to settle down and sexual desire to return!) For those women intending to use progesterone only contraceptives, please note that this is ideal only if you continue to breastfeed on demand. Breastfeeding confers additional contraception benefits but if one breastfeeds occasionally, then that benefit is reduced significantly.
- DVT (Deep Venous Thromboses) – DVT basically means depositing clots in the big veins of the body. These have local effects but run the risk of being dislodged and sent to the lungs, heart, brain or other organs. In the extreme, the dislodged clot can prove fatal. Anyone with history of having suffered from deep venous thrombosis should avoid estrogen containing hormonal contraceptives. Anyone with a previous history of DVT has a much higher risk of forming another clot and thus all known risk factors should be eliminated from their lifestyle if possible.
- Heavy smokers – Heavy smokers run the risk of developing deep venous thrombosis due to the effects of cigarettes on blood components predisposing to clot formation. This adds to the risk of estrogen predisposing to the same and making such a person more likely to suffer from DVT.
- Diabetes Mellitus – One of the things affected in diabetes is blood vessels. Thus use of estrogen may increase one’s risk of developing deep venous thromboses. In addition, estrogen may have unwanted effects on blood pressure and lipid metabolism. Thus, alternative contraception methods are advised in these women.
- Hypertension – Estrogen once again due to its effects on one’s body can cause an increase in blood pressure. In this regard, it is usually advisable for all people with very high pressures or poorly controlled blood pressure avoid hormonal contraceptives as they can aggravate the situation putting one at risk of complications.
- Abnormal vaginal bleed – Any person suffering from abnormal vaginal bleeding should be evaluated for a diagnosis before commencing hormonal contraceptives especially any containing estrogen. Some of the causes of abnormal vaginal bleeding can be tumors like of the uterus and some of these tumors are fueled by presence of estrogen.
- Heart disease – Patients with heart disease should ideally avoid hormonal contraceptives and especially those containing estrogen due to the risks of DVT and raised blood pressure which can aggravate the heart condition and cause additional strain on the heart.
- Liver disease – The liver is the primary detoxifying organ in the body. It is used to remove any excess or unwanted drugs in the body and thus if it is not functioning well, will result in more unwanted side effects of the hormones.
- Sickle cell disease – Estrogen increases viscosity of blood. For this reason, sicklers who are already prone to reduced oxygenation due to their abnormal red blood cells become more likely to go into crises if they use combined pills.
- Migraines – Patients who are prone to migraines should avoid estrogen containing contraceptives. In addition, those who have not had migraines but develop migraines after they start using the contraceptives should also have them withdrawn and changed to one they can tolerate.