Increasing would result in ovulation if the initial dose does not fit, but usually more than 2 tablets per day are not necessary.  

Both Letrozole and Clomid stimulate ovulation, but it is essential to stop taking them if pregnancy is suspected because both  Clomid and Letrozole might cause an increased risk of congenital defects.

Four years ago a study was published in a medical magazine Fertility and Sterility. The objective of study was to evaluate the possibility and incidence of congenital defects and malformations among mothers who conceived with the help of Clomid or Letrozole. Study included five fertility centers in Canada and more than  9 hundred newborns from women who after being diagnosed with infertility issues conceived with the help of Clomid and Letrozole.  Results showed that there was no major difference in the overall rates of major and minor malformations, including chromosomal abnormalities, cardiac abnormalities, among mothers who conceived with Letrozole or Clomid.

14 babies (2.4%) out of 514 conceived with letrozole were found to have congenital malformations and chromosomal abnormalities, and 19 (4, 8%) out of 397 newborns in the Clomid group, which appears to have double negative effect. Again doubled effect with major malformation: in the letrozole group was 1.2% and 3.0% in Clomid group; 02% of newborns had a ventricular septal defect in latrozole conceived group, while 1% in Clomid group; again the rate of congenital cardiac anomalies was significantly higher in Clomid group comparing to group conceived with Letrozole, where the rate was (only) 0.2%

One of the most serious side effects of letrozole is that if used and a woman becomes pregnant, there is a risk of birth defects.  Because the drug is not marketed as a fertility drug and the Food and Drug Administration has never approved the use of the medication in this manner, there is a liability if prescribed to a pregnant woman.  Therefore, if woman feels any of these pregnancy signs or symptoms , she should immediately contact her health provider. However, there are no research reports that indicate the drug is dangerous if given to a female prior to pregnancy.

Letrozole’s mechanism of action is based upon the drugs ability to reduce estrogen levels in females.  Low estrogen in the body can cause a female to have side effects from the medication, which can be treated.  The statistical information available on letrozole side effects are based upon the drug being used to treat cancer, not when used for fertility treatment.  Some of the side effects witnessed can include; hot flashes, headaches and breast tenderness.

Statistical information has not shown that letrozole puts a woman at an increased or decreased risk of miscarriage.  Letrozole should never be prescribed to a woman that is already pregnant, when studies were conducted using rats and mice being administered the drug, there was an increased risk of fetal death and malformations.  To date there have been no studies performed in human beings, but it is believed that the risks would be the same.

Letrozole is not a medication that should be taken without a prescription and strict medical supervision.  With all the information available, it is up to a woman to become educated and aware of the side effects of the drug and make the best decision for her unique situation.  With the advice of a medical professional, letrozole side effects can be managed and even avoided and a woman can conceive the child she has always longed for.