How long should I wait to conceive after stopping finasteride (dutasteride)?

Waiting Period After Stopping Finasteride Before Conception

Men should wait at least 3 months after discontinuing finasteride before attempting conception to ensure complete clearance of the medication and normalization of sperm parameters.

Effects of Finasteride on Male Fertility and Pregnancy

• Finasteride can affect male fertility by potentially causing oligospermia (low sperm count) in some men, particularly those who are already subfertile 1
• Studies have shown an average 11.6-fold increase in sperm counts after finasteride discontinuation, with 57% of men with severe oligospermia (<5 million/mL) improving to counts >15 million/mL after stopping the medication 1
• The FDA label notes that finasteride treatment for 24 weeks in healthy male volunteers showed a 0.6 mL (22.1%) median decrease in ejaculate volume with reduced total sperm per ejaculate, though these parameters remained within normal range 2
• These semen parameters typically return to baseline after discontinuation, with an average time to return of 84 weeks, though this varies significantly between individuals 2

Teratogenic Concerns

• Finasteride is a 5-alpha reductase inhibitor that can potentially cause abnormal development of male external genitalia if a pregnant woman is exposed to the medication 2
• Animal studies have shown that maternal exposure to finasteride during pregnancy can result in external genital abnormalities in male fetuses 2
• The FDA label specifically mentions concerns about the potential for finasteride to cause birth defects, particularly hypospadias (abnormal positioning of the urethral opening) in male fetuses 2

Recommended Waiting Period

• Based on the pharmacokinetics and effects on spermatogenesis, a minimum 3-month waiting period after stopping finasteride is recommended before attempting conception 1
• This timeframe allows for:
  1. Complete elimination of the drug from the body
  2. Production of new sperm that were not affected by the medication
  3. Normalization of semen parameters 1

Case Reports and Evidence

• There are documented cases of successful pregnancies after discontinuation of finasteride, suggesting that the effects on fertility are reversible 3
• One case report described a couple who conceived one month after the male partner stopped taking finasteride after 10 years of use, with a healthy baby delivered at full term 3
• Another study found no reports of adverse pregnancy outcomes among women whose partners were taking finasteride 4

Comparison to Other Medications Requiring Pre-Conception Discontinuation

• Other medications with potential reproductive concerns have similar recommended discontinuation periods:
  • Methotrexate: 3 months before conception 5, 6
  • Cyclophosphamide: 3 months before conception 5, 6
  • Mycophenolate: 6 weeks before conception 6
  • Anabolic androgenic agents: 2 months before conception 6

Important Considerations

• Men taking finasteride who are planning pregnancy should:
  1. Discuss their plans with their healthcare provider before stopping the medication
  2. Consider semen analysis if there are concerns about fertility
  3. Use reliable contraception during the 3-month waiting period after discontinuation
  4. Be aware that individual response may vary, and some men may require longer periods for complete normalization of sperm parameters 1

Common Pitfalls to Avoid

• Stopping finasteride abruptly without consulting a healthcare provider
• Attempting conception too soon after discontinuation
• Handling crushed or broken finasteride tablets by pregnant women (though the risk of significant absorption through skin contact is extremely low) 4
• Assuming that all men will experience fertility issues while taking finasteride (effects vary significantly between individuals) 1