Ovulation induction: definition and meaning
Ovulation induction is fertility treatment that uses medicine to stimulate the ovaries to develop and release an egg in people who don't ovulate, or ovulate rarely. Common options are letrozole, clomiphene and gonadotropin injections. The aim is usually one mature egg per cycle, timed with sex or insemination, while keeping the risk of twins and overstimulation low.
Who it can help
- People with anovulation, most often from PCOS
- Hypothalamic amenorrhea, sometimes treated with GnRH pumps or injections
- Some people with unexplained infertility, combined with insemination
- People with high prolactin (treated with a different medicine)
Main treatments
| Treatment | How it works | Notes |
|---|---|---|
| Letrozole | lowers estrogen so the brain makes more FSH | first-line for PCOS |
| Clomiphene | blocks estrogen signals in the brain | long-used tablet; twins in about 5 to 8% |
| Gonadotropin injections | FSH, sometimes with LH, given directly | needs close ultrasound monitoring |
| Metformin | improves insulin sensitivity | sometimes added in PCOS |
How cycles are monitored
Clinics often use ultrasound to count and measure follicles, and a blood test about a week after expected ovulation to confirm it. At home, many people use ovulation predictor kits. You can estimate timing with the Clomid ovulation calculator.
Looking after yourself
Treatment cycles bring hormone side effects, timed sex and a lot of waiting. Mood dips are common. It helps to agree on a plan, such as how many cycles before reviewing, and to protect time that has nothing to do with trying.
Contact your clinic for severe bloating, pelvic pain, sudden weight gain or breathlessness, which can signal ovarian hyperstimulation. Ask before starting each new cycle if your period is late.
Frequently asked questions
Is ovulation induction the same as IVF?
No. Ovulation induction helps the body release an egg naturally; in IVF eggs are collected and fertilized in a lab.
How successful is ovulation induction?
For people with PCOS, letrozole leads to ovulation in most and a live birth in roughly a quarter to a third over several cycles in trials.
Sources
This page is for information only and isn鈥檛 medical advice. If something worries you, please talk to a doctor.
Keep reading
What is letrozole?Letrozole is an aromatase inhibitor used off-label to trigger ovulation, often with PCOS. How it works, timing, side effects and how it compares with Clomid.
What is clomiphene (Clomid)?Clomiphene (Clomid) is a pill that triggers ovulation. How it works, when ovulation happens after taking it, side effects including mood, and the risks.
Clomid ovulation calculator: when will I ovulate on Clomid or letrozole?Free Clomid ovulation calculator: enter cycle day 1 and your first pill day to see when you'll likely ovulate and when to start LH tests. Letrozole too.
Anovulation: definition and meaningAnovulation means a cycle where no egg is released. What it is, why it happens, how it changes your period and mood, and when to talk to a doctor.
Infertility: definition and meaningInfertility means not getting pregnant after 12 months of regular unprotected sex, or 6 months if you're 35 or older. Causes, tests and next steps.