Oklahoma physicians in three specialty areas (ob/gyn, family practice, and general practice) were surveyed in regard to their practice of obstetrics. The 611 physicians who responded included a representative sample in regard to county of practice, rural vs urban, age, degree (DO & MD), specialty, and type of practice. Respondents accounted for 51% of the total 1989 births in Oklahoma during calendar year 1989. The vast majority (greater than 90%) of respondents report that they normally provide delivery services and prenatal care in combination. Cesarean sections are performed by almost all ob/gyns (97.6%), more than half of the family practitioners (56.5%), and a very few general practitioners (18.9%). Half of all physicians responding have made changes in their obstetric practice in the last 3 years. The most common changes are: reducing care of medically high risk, uninsured, and/or Medicaid patients. The most important reasons for these changes are: fear of obstetric malpractice suits, inconvenience of obstetrics and excessive professional liability insurance premiums. Specific reasons for reducing care to medically high risk patients were reported to be: increased medical legal liability, belief that high risk patients should be cared for by specialists, and lack of Medicaid reimbursement for diagnostic services. Almost 90% of the physicians responding to the survey are required to carry a minimum amount of professional liability insurance by the hospital where they practice with the most frequently stated amount being $1,000,000. Current average "global fees" reported by the respondents were $1,202 for a spontaneous vaginal delivery and $1,543 for a cesarean delivery.(ABSTRACT TRUNCATED AT 250 WORDS)