Clomiphene Citrate was the original ‘fertility pill’, and it is still widely used. It’s the most ‘natural’ scientifically proven fertility treatment – no injections, and you still have sex to become pregnant.
Clomiphene is mainly used for two groups of people:
- Women who don’t ovulate or who have irregular cycles.
- Women with a shorter duration of unexplained infertility.
Letrozole is a new alternative for women who don’t ovulate or have irregular cycles. Overall, about 20-30% of women aged 37 and under have a child over a course of up to 3-4 cycles of Clomiphene or Letrozole.
There is a slightly increased chance of twins, which can be reduced to around 5–10% by checking the body’s response to the medication using a blood test or an ultrasound scan.
How it works
Clomiphene & Letrozole
As we have mentioned in how hormones work:
- The pituitary gland at the base of the brain produces a hormone called FSH which makes follicles grow in the ovary;
- The follicles then make a hormone called oestradiol (E2);
- When the pituitary gland senses increasing levels of oestradiol, it reduces the amount of FSH it releases.
Producing one follicle is the aim for women having clomiphene or letrozole to restore a regular cycle, while 2-3 follicles is the aim when using clomiphene treatment for unexplained infertility.