Scott Alexander analyzes the complex relationship between contraception and abortion rates, concluding that in societies where contraceptives are already legal, increasing access likely decreases abortion rates. Longer summary

Scott Alexander examines the complex relationship between contraception use and abortion rates. He first presents arguments suggesting contraception might increase abortion rates, including the Peltzman effect where safety measures lead to riskier behavior. He then explores evidence that contraception decreases abortion rates, including historical data and controlled studies. Scott concludes that while legalizing contraceptives in a society might initially increase abortion rates as part of a broader cultural shift, in societies where contraceptives are already legal, increasing access likely decreases abortion rates. He especially emphasizes that highly effective contraceptives like implants or RISUG are very likely to reduce abortions when they replace less effective methods. Shorter summary