Background Surveillance of drug quality for antibiotics, antiretrovirals, antimalarials and vaccines is better established than surveillance for maternal health drugs in low-income countries, particularly uterotonic drugs for the prevention and treatment of postpartum hemorrhage. The objectives of this study are to: assess private sector accessibility of four drugs used for uterotonic purposes (oxytocin, methylergometrine, misoprostol, valethamate bromide); and to assess potency of oxytocin and methylergometrine ampoules purchased by simulated clients. Methods The study was conducted in Hassan and Bagalkot districts in Karnataka state and Agra and Gorakhpur districts in Uttar Pradesh state. A sample of 877 private pharmacies was selected (using a stratified, systematic sampling with random start), among which 847 were successfully visited. The target sample size for assessment of accessibility was 50 pharmacies per drug, per district. The target sample size for potency assessment was 100 purchases each of oxytocin and methylergometrine across all districts. Successful drug purchases varied by state. Results In Agra and Gorakhpur, 90%-100% of visits for each of the drugs resulted in a purchase. In Bagalkot and Hassan, only 29%-52% of visits for each drug resulted in a purchase. Regarding potency, the percent of active pharmaceutical ingredient was assessed using United States Pharmacopeia monograph #33 for both drugs; 193 and 188 ampoules of oxytocin and methylergometrine, respectively, were assessed. The percent of oxytocin ampoules outside manufacturer specification ranged from 33%-40% in Karnataka and from 22%-50% in Uttar Pradesh. In Bagalkot and Hassan, 96% and 100% of the methylergometrine ampoules were outside manufacturer specification, respectively. In Agra and Gorakhpur, 54% and 44% were outside manufacturer specification, respectively. Conclusion Private sector accessibility of uterotonic drugs in study districts in Karnataka warrants attention. Most importantly, interventions to assure quality oxytocin and particularly methylergometrine are needed in study districts in both states.