Femara And Infertility
Femara is the latest drug which is being used for infertility treatment. Fertility drugs are also being used now for infertility treatment. These drugs will make the egg develop and it will help women who are facing any difficulty while ovulating. This is also known as ovulation induction. These fertility drugs can also be used to increase the chances of a pregnancy in women who are already ovulating and this is known as super ovulation. Many fertility clinics have used clomiphene citrate (Clomid, Serophene) for many years to induce ovulation and for super ovulation. This has also been a very effective medicine. But clomiphene citrate stays in the body for a very long time and it can cause some damage to the cervical mucus and the lining of the uterus. Women who have PCOS - polycystic ovary syndrome might not respond well to clomiphene citrate. Fertility drugs which are given in the form of injections are known as gonadotropins. These help in inducing ovulation and the chances of a pregnancy are much better when compared to clomiphene citrate. But there are many patients who do not like injections and gonadotropins also increase the chance of a multiple pregnancy. Femara is usually used to treat women who have had breast cancer and this belongs to a class of medications which is known as aromatase inhibitors.
Women who took Femara while they were pregnant had a greater chance of having children who had birth defects. Novartis, the company that makes letrozole, found that out of 13 women who had taken Femara, 2 of them had children with birth defects. In the United States, letrozole is a name which means birth defects. Novartis has not got FDA certification to sell letrozole as a fertility drug and it is worried about giving this drug in times of a pregnancy.
But there have no cases of children having birth defects if letrozole was given before the pregnancy. Femara is a medicine which gets metabolized properly and you cannot find high levels of Femara in the blood and the tissues. There is another pharmaceutical company, Serono, which is conducting studies with a similar drug called anastrozole and it wants to get the FDA approval before selling this as a fertility drug.
Aromatase is an enzyme which helps in producing oestrogen in the body. Femara suppresses aromatase and also reduces the production of oestrogen. Clomiphene citrate blocks the oestrogen receptors. Due to this the pituitary gland has to secrete more hormones to make the ovaries work. The hormones FSH and LH will increase ovulation in women and it will also increase the quantity of the eggs in women who are already ovulating. Many studies have used letrozole as a drug. A study was conducted on 12 women who did not respond well to clomiphene citrate and used letrozole. Ovulation took place in 9-12 cycles and three women were able to conceive.
Studies were also done to compare letrozole and clomiphene citrate. Ten women took clomiphene citrate and nine women took letrozole. But this study was inconclusive and could not show any difference in women ovulating, the quantity of eggs and the thickness of the uterus lining. But a more recent study has shown that letrozole makes the uterus lining thicker and the risk of miscarriage also reduces. But the actual dose of letrozole has not yet been determined. It has been given at 2.5mg, 5mg and 7.5mg. Different doses have been given in different studies and the length of the dose is for five days. The pregnancy rate for letrozole was much higher than clomiphene citrate and even gonadotropins. But later studies showed that the pregnancy rate for letrozole was lower than that of gonadotropins. But women who are older have a lower chance of success. But letrozole has proved successful where other treatments have failed.