Objective To evaluate the effects of intravenous anesthesia with propofol on the number of natural killer (NK) cells and pregnancy outcome of patients undergoing oocyte retrieval. Methods According to the random number table method, 110 patients, aged 20 to 40 years, American Society of Anesthesiologists (ASA) Ⅰ or Ⅱ, who were scheduled for in vitro fertilization and embryo transfer (IVF‑ET) were enrolled and divided into two groups (n=55): a propofol group (group P) and a ibuprofen group (group C). Their general clinical data were collected before operation; the vital signs were monitored after entry into the operating room and venous access was established. Group P was intravenously infused with 2.0‒2.5 mg/kg of propofol and the operation started when the score of sedation reached 6, with anesthesia maintenance with propofol at 8‒12 mg·kg−1·h−1. Group C was vaginally placed with ibuprofen suppository 15 min before operation. Then, their age, body mass index (BMI), the duration of infertility, operation time, ASA grades, the days of superovulation, total dose of ovulation induction, and the levels of basal follicle‑stimulating hormone (FSH), luteinizing hormone (LH) and estradiol (E2) were recorded. The mean arterial pressure (MAP), heart rate and pulse oxygen saturation (SpO2) were recorded before anesthesia induction (T0), immediately after operation (T1), immediately after operation (T2) and 10 min after operation (T3), VAS scores at T3 and adverse reactions were recorded. The venous blood samples were collected at T0, T2, day 1 after operation (T4) and before embryo transfer (T5) to measure the number of NK cells by flow cytometry. Their pregnancy outcomes were recorded. Results MAP and heart rate in group P were lower than those in group C at T1, T2 and T3 (P<0.05). Compared with those at T0, MAP and heart rate in group P increased at T1 and decreased at T3 (P<0.05), and MAP and heart rate in group C increased at T1, T2 and T3 (P<0.05). There was no statistical difference in SpO2 at each time point between the two groups (P>0.05). The VAS score in group P was lower than that in group C at T3, and the number of movement cases in group P was lower than that in group C (P<0.05). There was no statistical difference in the incidence of aspiration inhibition and postoperative nausea and vomiting between the two groups (P>0.05). The number of NK cells in group P was less than that in group C at T2 (P<0.05). The number of NK cells decreased at T2 compared with T0 in group P (P<0.05). There was no statistical difference in the rates of zygote formation, embryo formation, early abortion and clinical pregnancy between the two groups (P>0.05). The number of oocytes and oocyte retrieval rate in group P were higher than those in group C (P<0.05). Conclusions Intravenous anesthesia with propofol can reduce the number of NK cells during oocyte retrieval operation. Although it does not significantly improve the outcome of single pregnancy, it can achieve a higher oocyte retrieval rate and promote the outcome of subsequent pregnancy.