How to Take Letrozole 7.5mg for Fertility
Start with 2.5 mg daily for 5 days (cycle days 3-7), and only escalate to 7.5 mg in subsequent cycles if you fail to develop adequate follicles or ovulate with lower doses. 1
Standard Dosing Protocol
- Begin with 2.5 mg daily taken orally for 5 consecutive days, starting on day 3,4, or 5 of your menstrual cycle (most commonly day 3-7) 1
- If you don't respond adequately (no follicle development or ovulation), increase to 5 mg daily in the next cycle 1
- Only escalate to 7.5 mg daily if you continue to show inadequate response at 5 mg 1
- The medication is taken for exactly 5 days, then stopped 1, 2
Essential Monitoring Requirements
You must have ultrasound monitoring during each treatment cycle—this is not optional. 1, 3 This monitoring serves two critical purposes:
- Confirms that follicles are developing appropriately (looking for follicles reaching 18mm diameter) 1
- Prevents dangerous multiple pregnancies by ensuring you're not developing too many mature follicles 1, 3
- Tracks endometrial thickness to ensure adequate uterine lining 1
Your physician will typically start ultrasound monitoring around cycle day 10-12 and continue until a mature follicle is identified 4.
Timing Intercourse or Insemination
- When your largest follicle reaches 18mm on ultrasound, you'll receive an hCG injection (typically 10,000 units) to trigger ovulation 4
- Have timed intercourse or undergo intrauterine insemination (IUI) 24-36 hours after the trigger injection 5
Treatment Duration and Next Steps
- Continue letrozole for 3-6 cycles before considering it unsuccessful 1, 3
- If pregnancy doesn't occur after 3-6 cycles, add intrauterine insemination (IUI) to your letrozole treatment 1, 6
- If letrozole with IUI fails after an appropriate trial, referral for IVF is recommended 1, 3
Why Higher Doses May Not Be Better
While 7.5 mg produces more follicles and faster follicle development compared to lower doses 7, 2, research shows no improvement in actual pregnancy rates with 7.5 mg versus 2.5 mg 2. A randomized trial found pregnancy rates of 25.8% with 5 mg versus 21.2% with 7.5 mg—not statistically different 5. Another study confirmed that 7.5 mg produced significantly more follicles but identical pregnancy and miscarriage rates compared to 2.5 mg 2.
The practical implication: start low and only escalate if you're not ovulating, as higher doses increase follicle numbers (and thus multiple pregnancy risk) without improving your chances of getting pregnant 2.
Critical Safety Considerations
- Never skip ultrasound monitoring—this is the only way to prevent high-order multiple pregnancies (triplets or more), which carry serious maternal and fetal risks 1, 3
- Letrozole maintains normal endometrial thickness even at high doses, unlike clomiphene citrate 1, 3
- The drug keeps estrogen levels near physiologic ranges, reducing the risk of ovarian hyperstimulation syndrome (OHSS) 1, 3
- Miscarriage rates with letrozole (14-20%) are similar to spontaneous pregnancies 8
Common Pitfall to Avoid
The most dangerous mistake is attempting letrozole treatment without proper ultrasound monitoring, as you cannot know how many follicles are developing without imaging 1, 3. Multiple mature follicles significantly increase the risk of high-order multiple pregnancies, which are associated with severe maternal complications (preeclampsia, gestational diabetes, hemorrhage) and poor neonatal outcomes (extreme prematurity, cerebral palsy, death).