General anesthesia versus monitored anesthesia care with remifentanil for assisted reproductive technologies: effect on pregnancy rate

Pain Management during Ultrasound Guided Transvaginal Oocyte Retrieval - A Narrative Review

Transvaginal oocyte retrieval (TVOR), done for the purpose of assisted reproduction can instigate enormous pain and therefore requires adequate analgesia with the least adverse effects. As the procedure involves retrieving oocytes for in vitro fertilisation, the effect of the anaesthetic drugs on the oocyte quality should also be considered. This review focuses on the various modes of anaesthesia and the anaesthetic drugs which can be administered safely to provide effective analgesia in normal and in special conditions such as women with pre-existing comorbidities. Medline, Embase, PubMed and Cochrane electronic databases were searched according to modified Preferred Reporting Items for Systemic Reviews and Meta-Analyses guidelines. According to this review, conscious sedation appears to be the most preferred mode of anaesthesia in women undergoing TVOR owing to fewer adverse effects, faster recovery, better patient and specialist comfort and the least effect on oocyte quality and embryo development. Combining it with paracervical block resulted in lesser consumption of the anaesthetic drug, which may have a beneficial effect on the oocyte quality.

Isoflurane impairs oogenesis through germ cell apoptosis in C. elegans

Anesthetic isoflurane has been reported to induce toxicity. However, the effects of isoflurane on fecundity remain largely unknown. We established a system in C. elegans to investigate the effects of isoflurane on oogenesis. Synchronized L4 stage C. elegans were treated with 7% isoflurane for 4 h. Dead cells, ROS, embryos, and unfertilized eggs laid by hermaphrodites were measured by fluorescence imaging and counting. The C. elegans with losses of ced-3, cep-1, abl-1, male C. elegans, and oxidative stress inhibitor N-acetyl-cysteine were used in the interaction studies. We found that isoflurane decreased the numbers of embryos and unfertilized eggs and increased the levels of dead cells and ROS in C. elegans. The isoflurane-induced impairment of oogenesis was associated with abl-1, ced-3, but not cep-1. N-acetyl-cysteine attenuated the isoflurane-induced impairment of oogenesis in C. elegans. Mating with male C. elegans did not attenuate the isoflurane-induced changes in oogenesis. These findings suggest that isoflurane may impair oogenesis through abl-1- and ced-3-associated, but not cep-1-associated, germ cell apoptosis and oxidative stress, pending further investigation. These studies will promote more research to determine the potential effects of anesthesia on fecundity.

Comparison of Two Different Sedation Protocols during Transvaginal Oocyte Retrieval: Effects on Propofol Consumption and IVF Outcome: A Prospective Cohort Study

(1) Background: There has been various reports on the potential impact of anesthetic agents used during oocyte retrieval (OR) on the impairment of the capacity of the oocyte for fertilization and subsequent embryo quality; results have been conflicting; (2) Methods: The effects of two different sedation protocols during OR in two groups of patients undergoing In Vitro Fertilization/Intra-Cytoplasmic Sperm Injection IVF/ICSI, were compared on propofol consumption and on in vitro fertilization (IVF)/ICSI success. The study group received dexmedetomidine and fentanyl, while the control remifentanil and midazolam. In a prospective cohort study, we encompassed 72 cycles/patients. The administered dose of propofol per patient and fertilization rates were the primary outcomes, while anesthesiological parameters and IVF/ICSI outcomes were the secondary endpoints; (3) Results: We found a significant increase in propofol consumption in the study compared to the control group (77.0 ± 10.6 mg vs. 12.1 ± 6.1; p < 0.001), but fertilization rates were similar (p = 0.469). From the secondary anesthesiological outcomes, the post anesthesia discharge scores were better in the control group (15.0 (13.5 min) vs. 5.0 (10.0 min), p = 0.028). From the IVF/ICSI secondary outcome parameters, we found a higher quality of embryos on day three in the study compared to the control group (p = 0.040). The comparison of the other secondary outcomes yielded non-significant differences; (4) Conclusions: The use of dexmedetomidine, as an alternative agent during OR, was associated with higher propofol consumption as a rescue dose compared to remifentanil but was linked with similar fertilization rates and higher quality of embryos produced.

High level of satisfaction among women who underwent oocyte retrieval without anesthesia

OBJECTIVE

To assess the level of satisfaction of women undergoing transvaginal oocyte retrieval (TOR) without anesthesia as well as the comfort of the gynecologists.

DESIGN

Single-center, prospective cohort study of women undergoing TOR from July 2017 to January 2018.

SETTING

This study was conducted in an academic public hospital.

PATIENT(S)

Women with ≤15 follicles for retrieval were eligible. Women with body mass index > 35, difficult vaginal approach, endometrioma > 5 cm, or pelvic inflammatory disease were excluded.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Our primary endpoint was patient satisfaction. Secondary endpoints were women's willingness to recommend or undergo the procedure again without anesthesia, anxiety levels before the procedure, expected level of pain, actual pain levels during the procedure, and gynecologist's level of difficulty or technical compromise.

RESULT(S)

During the study period, 500 TORs were performed, of which 402 (80%) were screened for study eligibility. Overall, data were analyzed for 50 eligible women who had their first in vitro fertilization cycle (participating in the study) without anesthesia. High rates of satisfaction were reported, and 90% would recommend the procedure without anesthesia to their friends. Physicians graded the difficulty of the procedure as very easy in 35 procedures; in only two procedures was difficulty reported.

CONCLUSION(S)

TOR without anesthesia is feasible, with a relatively high satisfaction rate from both patients and gynecologists, suggesting that it should be considered in selected women.

Comparison of chemical pregnancy rates according to the anesthetic method during ultrasound-guided transvaginal oocyte retrieval for in vitro fertilization: a retrospective study

Background

Oocyte retrieval is the most important procedure in in vitro fertilization (IVF). Various anesthetic methods are used to control a patient’s anxiety and pain during IVF; however, there are no recommended anesthetic methods at present. In this study, we retrospectively investigated chemical pregnancy rates according to the anesthetic method used for oocyte retrieval.

Methods

We reviewed records of patients who underwent oocyte retrieval between January 1, 2012 and December 31, 2017. Patients were divided into the spinal anesthesia (SA) and monitored anesthesia care (MAC) groups. The primary outcome was chemical pregnancy rate after IVF.

Results

The study included 95 patients. SA was administered in 77 (81%) and MAC in 18 (19%). The overall chemical pregnancy rate was 32.6% (31/95). According to the anesthetic method, the pregnancy rate was 32.5% (25/77) in the SA group and 33.3% (6/18) in the MAC group. There was no statistical difference in the pregnancy rate between the groups (P = 0.575). The procedural time was significantly shorter in the SA group than in the MAC group (P < 0.001).

Conclusions

Chemical pregnancy rates were not significantly different between the SA and MAC groups. However, the procedure duration was shorter in the SA group than in the MAC group.

Hemodynamic parameters and reproductive outcome after intracytoplasmic sperm injection and fresh embryo transfer in patients undergoing oocyte retrieval with general anesthesia using fentanyl, remifentanil or alfentanil - A randomized clinical trial

OBJECTIVE

Anesthesia for assisted reproductive technology is very important to provide less stressful and painful environment for patients, with minimal side effects on oocytes. In the present study, we aimed to evaluate hemodynamic parameters, recovery time and intracytoplasmic sperm injection (ICSI) outcome among patients underwent anesthesia with fentanyl, remifentanil or alfentanil.

MATERIAL AND METHODS

This randomized double-blinded clinical trial was conducted in patients undergoing anesthesia for transvaginal ultrasound guided oocyte retrieval (TUGOR). Patients were randomly allocated to alfentanil (A; 15 μg/kg), fentanyl (F; 1.5 μg/kg) or remifentanil (R; 1.5 μg/kg) groups.

RESULTS

Three hundred forty patients were assessed for eligibility and randomized for transvaginal oocyte retrieval following general anesthesia and 105 were lost to follow up. No statistically significant differences were noted among groups regarding basic characteristics. Although, time to respond to verbal command was significantly different among groups (A: 1.99 ± 1.64, F: 2.56 ± 1.72, R: 1.78 ± 1.34, P = 0.014). There were no significant differences among groups with respect to the first and second postoperative pain intensity, patient satisfaction, pre-induction and post-induction systolic and diastolic blood pressure (BP). Terminal systolic (A: 101.61 ± 9.15, F: 105.29 ± 12.61, R: 102 ± 12.91, P = 0.01) and diastolic (A: 59.97 ± 9, F: 65.63 ± 9.13, R: 63.69 ± 11.01, P = 0.003) BP was significantly different among groups. The fertilization rate was significantly different among groups (A: 51.6%, F: 54.4%, R: 62.2%, P = 0.018). Implantation rate, biochemical and clinical pregnancy rate was similar among groups.

CONCLUSIONS

The results of present study demonstrated that all three opioids have the same efficiency, in regards to patient satisfaction and pregnancy outcome. However, Anesthesia with alfentanil compared with fentanyl and remifentanil, seems to be inferior for TUGOR due to higher effect on fertilization rate and less hemodynamic stability.

REGISTRATION NUMBER

IRCT201410258677N4.

Efficacy of bispectral index monitoring for prevention of anestheticawareness and complications during oocyte pick-up procedure

Background/aim: This study was planned by considering that the use of bispectral index (BIS) monitoring ensures sufficient depth of anesthesia and avoids anesthetic awareness and patient movement in the oocyte pick-up (OPU) procedure.Materials and methods: Ninety-eight patients undergoing OPU were randomly divided into 2 groups as the control group (n = 48) and BIS group (n = 50). After propofol and remifentanil induction, the control group was given additional propofol according to reaction response, while the BIS group was given propofol at BIS values of 60 and above with the aim that BIS values be 40?60. Total procedure time, recovery time, patient movement, additional propofol consumption, total number of oocytes, and awareness during anesthesia were recorded. Results: Demographic data were similar in the two groups (P > 0.05 for all). The recovery time in the BIS group was significantly shorter compared to the control group (P < 0.001) while additional propofol consumption was found to be significantly lower (P < 0.001). Baseline BIS values fell compared to all other times after induction significantly (P < 0.001). No patient had anesthesia awareness.Conclusion: During the OPU procedure BIS monitoring is considered to prevent anesthesia awareness, intraoperative movement, and complications caused by insufficient anesthetic use as it ensures optimal doses of anesthetic agents used and early recovery.

Flurbiprofen Axetil Provides Effective Analgesia Without Changing the Pregnancy Rate in Ultrasound-Guided Transvaginal Oocyte Retrieval: A Double-Blind Randomized Controlled Trial

BACKGROUND

In this prospective double-blind randomized study, we evaluated the analgesic effect and potential effect on pregnancy rate of the nonsteroidal anti-inflammatory drug flurbiprofen axetil in patients undergoing ultrasound-guided transvaginal oocyte retrieval under propofol-remifentanil anesthesia.

METHODS

A total of 200 patients scheduled to undergo ultrasound-guided transvaginal oocyte retrieval were randomly allocated to receive 1.5 mg/kg of flurbiprofen axetil (FA group) or placebo (control group) 30 minutes before the procedure. Postoperative pain scores, embryo implantation rate, and pregnancy rate were recorded. Neuroendocrine biomarkers and prostaglandin E2 levels in follicular fluid were tested after oocyte retrieval.

RESULTS

Patients in the FA group awakened earlier after surgery than patients in the control group (3.3 ± 2.6 vs 5.3 ± 3.4 minutes, P < .05) and had lower pain scores than patients in the control group (2.0 [0.0, 2.8] vs 5.0 [3.0, 5.0], P< .001). The difference in pregnancy rates between the 2 groups (44%-44%) was 0% (conventional 2-sided 95% confidence interval, -13.8% to 13.8%). The lower limit of the 90% 1-sided confidence interval for this difference was -9.0%, which was within the predefined noninferiority margin of -15.0%. The concentration of prostaglandin E2 in follicular fluid was decreased in the FA group (24.51 ± 1.52 vs 25.15 ± 1.49 pg/mL, P = .039), although the difference does not appear to be clinically important.

CONCLUSIONS

Flurbiprofen axetil given before ultrasound-guided transvaginal oocyte retrieval for patients under propofol-remifentanil general anesthesia relieves pain without any detrimental effect on clinical pregnancy rate.

A Prospective Randomized Trial Comparing Dexmedetomidine and Midazolam for Conscious Sedation During Oocyte Retrieval in An In Vitro Fertilization Program

Background:

Various sedative and analgesic techniques have been used for pain relief during oocyte retrieval which is the most painful part of in vitro fertilization (IVF) procedures.

Aim:

This study aimed at comparing dexmedetomidine and midazolam for conscious sedation in women undergoing transvaginal oocyte retrieval during an IVF program.

Settings and Design:

Prospective randomized double-blinded comparative study.

Patients and Methods:

Fifty-two patients undergoing oocyte retrieval in their first IVF cycle were randomly allocated into two equal groups. The intervention started with giving fentanyl1 mcg/kg intravenous (IV) followed by paracervical block in both groups. Then, subjects in group (D) received dexmedetomidine at a loading dose of 1 μg/kg IV over 10 min followed by 0.5 μg/kg/h infusion until Ramsay Sedation Scale (RSS) reached 3–4. Patients in group (M) received a loading dose of midazolam 0.06 mg/kg IV over 10 min followed by 0.5 mg incremental doses until RSS reached 3–4.

Statistical Analysis:

Statistical analysis was performed using SPSS program version 19 and EP 16 program.

Results:

Visual analog scale scores significantly decreased in group D than group M at 5 and 10 min during the procedure (P = 0.03 and 0.01, respectively), and at 20 min during postanesthesia care unit (PACU) time (P = 0.04). Intraoperative rescue sedation by propofol and postoperative rescue analgesia by acetaminophen showed a highly significant decrease (P < 0.01) in group D compared with group M. Furthermore, the time of PACU stay was significantly less (P < 0.01) in group D (49.03 ± 12.8 min) compared to group M (62.5 ± 18.34 min). Although significant bradycardia was noted in group D (23% of patients) during the procedure (P = 0.02), no cases were reported in group M. Patient satisfaction was significantly higher in group D (P < 0.1).

Conclusion:

Dexmedetomidine is an effective analgesic alternative to midazolam during oocyte retrieval for IVF. It offered not only a shorter PACU stay without significant side effects, but also better overall patient satisfaction scores.

Anesthesia Related Toxic Effects on In Vitro Fertilization Outcome: Burden of Proof

Management of pain and anxiety during oocyte retrieval makes anesthesia an important part of the in vitro fertilization (IVF) procedures. There are many studies investigating the influence of anesthesia on IVF success. This review article provides an overview of published data regarding the potential toxic effects of different anesthetic techniques (Loco-regional, general anesthesia (GA), and monitored anesthesia care (MAC)), different anesthetic agents, and alternative medicine approach (principally acupuncture) on the IVF outcome. From our analysis, evidence of serious toxicity in humans is not well established. Trials regarding different anesthetic techniques ended up without clear conclusions. Studies about GA came up with conflicting results. A few trials relate GA with lower pregnancy rates, although some others failed to prove this conclusion. Furthermore, detectable amounts of some anesthetic agents are measurable in the follicular fluid but these findings are not strongly associated with toxicity. MAC and Loco-regional anesthesia appear as safe alternative choices and there is evidence of improved outcome. Whereas acupuncture may provide assistance increasing IVF success according to some trials, some others could not obtain these effects. Questions about the appropriate time of application and the underlying mechanism of action are not answered yet, so further investigation should be done.

Patient-Controlled Remifentanil Analgesia as Alternative for Pethidine with Midazolam During Oocyte Retrieval in IVF/ICSI Procedures: A Randomized Controlled Trial

BACKGROUND

Pethidine with midazolam-induced conscious sedation for pain relief during transvaginal oocyte retrieval for in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) procedures is associated with residual pain and oversedation. Patient-controlled analgesia (PCA) with remifentanil may serve as an alternative for pethidine. We investigated whether PCA remifentanil with diclofenac was associated with improved periprocedural pain relief than pethidine analgesia during IVF/ICSI procedures, with sedation scores, safety profiles, and patient satisfaction as secondary endpoints.

METHODS

Seventy-six women were randomized to receive pethidine (2 mg/kg i.m.) and midazolam (7.5 mg)-induced conscious sedation (n = 40) or PCA with remifentanil and diclofenac (50 mg; n = 36). The Numeric Rating Scale, McGill Pain Questionnaire (MPQ), Ramsey Sedation Scale, and a 5-day pain-and-discomfort diary were used to evaluate pain and sedation levels.

RESULTS

There were no differences in baseline characteristics and reproductive outcomes between both groups. Periprocedural pain scores were comparable for remifentanil and pethidine groups (4 [3 to 7] vs. 6 [4 to 8]; P = 0.13). Pain scores in the pethidine group were significantly lower at 30 minutes after the procedure (1 [0 to 3] vs. 2 [1 to 5]; P = 0.016), but at cost of higher sedation levels when compared to remifentanil (4 [2 to 4] vs. 2 [2 to 2]; P < 0.001). Patient satisfaction was higher, and MPQ scores were lower in the remifentanil group. There were no differences in safety profiles between both analgesics.

CONCLUSIONS

Patient-controlled analgesia with remifentanil showed a similar reduction in pain scores than pethidine with midazolam during oocyte retrieval, while pethidine induced the highest pain relief after the procedure. However, PCA remifentanil was associated with less sedation and a better patient satisfaction profile than pethidine.

Does Spinal Analgesia have Advantage over General Anesthesia for Achieving Success in In-Vitro Fertilization?

OBJECTIVE

Because of high psychological burden and considerable costs of in-vitro fertilization, it is greatly important to identify all factors that may influence its results. In this study, general anesthesia and spinal analgesia used for oocyte retrieval were compared in terms of success in treating infertility among couples who had undergone in-vitro fertilization at an infertility center in Tehran, Iran.

METHODS

This cohort study that was based on analysis of patient records at Mirza Kochak Khan Hospital, Tehran University of Medical Sciences, in 2008-2009. In this study, the status of chemical pregnancy among those who experienced general anesthesia or spinal anesthesia for in-vitro fertilization for the first time were compared, and the possible effects of clinical and laboratory factors using logistic regression models were considered.

RESULTS

Considering the number of transferred embryos, underlying cause of infertility and fetus grade, it was found that practicing spinal anesthesia is significantly related to increased chance of chemical pregnancy (adjusted Odds Ratio=2.07; 95% CI: 1.02,4.20; p=0.043).

CONCLUSION

According to analysis of recorded data in an infertility treatment center in Iran, it is recommended to use spinal anesthesia instead of general anesthesia for oocyte retrieval to achieve successful in-vitro fertilization outcome. This can be studied and investigated further via a proper multicentric study in the country.

Pharmacologic neuroprotective strategies in neonatal brain injury

This article explains the mechanisms underlying choices of pharmacotherapy for hypoxic-ischemic insults of both preterm and term babies. Some preclinical data are strong enough that clinical trials are now underway. Challenges remain in deciding the best combination therapies for each age and insult.

A comparison of three different target-controlled remifentanil infusion rates during target-controlled propofol infusion for oocyte retrieval

OBJECTIVE

To evaluate the effects of three different target-controlled remifentanil infusion rates during target-controlled propofol infusion on hemodynamic parameters, pain, sedation, and recovery score during oocyte retrieval.

METHODS

Sixty-nine women were scheduled for oocyte retrieval. Target-controlled propofol infusion at an effect-site concentration of 1.5 μg/mL was instituted. The patients were randomly allocated to receive remifentanil at an effect-site concentration of either 1.5 (group I, n = 23), 2 (group II, n = 23) or 2.5 ng/mL (group III, n = 23). Hemodynamic variables, sedation, pain, the Aldrete recovery score, and side effects were recorded.

RESULTS

Hemodynamic variables, sedation and pain scores and the number of patients with the maximum Aldrete recovery score 10 min after the procedure were comparable among the groups. The number of patients in group III with the maximum Aldrete recovery score 5 min after the procedure was significantly lower than that in groups I and II. One patient in group II and one patient in group III suffered from nausea.

CONCLUSION

Similar pain-free conscious sedation conditions without significant changes in hemodynamic parameters were provided by all three protocols. However, target controlled infusion of remifentanil at 1.5 or 2 ng/mL proved superior at providing early recovery compared to 2.5 ng/mL.

Office based--is my anesthetic care any different? Assessment and management

Office-based anesthesia (OBA) is a unique and challenging venue, and, although the clinical outcomes have not been evaluated extensively, existing data indicate a need for increased regulation and additional education. Outcomes in OBA can be improved by education not only of anesthesiologists but also of surgeons, proceduralists, and nursing staff. Legislators must be educated so that appropriate regulations are instituted governing the practice of office-based surgery and the lay public must be educated to make wise, informed decisions about choice of surgery location. The leadership of societies, along with support from the membership, must play a key role in this educational process; only then can OBA become as safe as the anesthesia care in traditional venues.

Anaesthetic Issues in In-vitro Fertilisation

BACKGROUND

Ultrasonically guided transvaginal oocyte retrieval is a relatively short procedure that is performed on an outpatient basis. Any anaesthetic technique may interfere with certain aspects of human oocyte fertilisation or embryo implantation. The optimal anaesthetic technique should allow good surgical anaesthesia with minimal side effects, a short recovery time and high rate of successful pregnancy.

METHOD

We present our experience and evaluation of the various techniques studied to carry out this technique.

RESULTS AND CONCLUSION

Amongst the various available total intravenous anaesthesia options, propofol/ remifentanil or fentanyl technique of sedation appears to be safe and effective.

Effect of nitrous oxide on propofol requirement during target-controlled infusion for oocyte retrieval

BACKGROUND

Oocyte (egg) retrieval for in-vitro fertilization is a relatively short procedure, usually performed as an outpatient. Propofol is a suitable anesthetic agent. Target-controlled infusion is a recently developed system that aids rapid recovery from propofol anesthesia. This study sought to determine the target concentration of propofol required to prevent movement in 50% (Cp50) and 95% (Cp95) of women during oocyte retrieval, and investigated whether supplemental nitrous oxide (N2O) modified the Cp50 and Cp95.

METHODS

Forty-seven women scheduled for oocyte retrieval were randomly selected to receive either O2-air mixture (control group; n = 23) or 50% O2-N2O mixture (Nitrous oxide group; n = 24). Propofol was infused using a target-controlled infusion system with the concentration determined by up-down sequential allocation using 0.5 microg/mL step size. Transvaginal oocyte retrieval was performed after reaching target blood concentration. Patient responses to oocyte retrieval were noted as either no movement or movement.

RESULTS

Using target-controlled infusion the Cp50 was 4.1 microg/mL in the control group and 3.3 microg/mL in the nitrous oxide group. Calculated Cp95 values were 4.0 microg/mL and 5.1 microg/mL with and without 50% nitrous oxide respectively.

CONCLUSIONS

The Cp50 value for target-controlled infusion propofol during oocyte retrieval was significantly reduced by a factor of 1.24 (95% CI 1.07-1.44) with the use of 50% nitrous oxide.

Auricular electro-acupuncture as an additional perioperative analgesic method during oocyte aspiration in IVF treatment

BACKGROUND

The aim of this study was to compare the pain-relieving effect and the subjective well-being between auricular electro-acupuncture (EA) analgesia, auricular acupuncture (A) and conventional analgesia with remifentanil (CO).

METHODS

A total of 94 women undergoing IVF were randomized to auricular acupuncture with (EA, n = 32) or without (A, n = 32) continuous 1 Hz auricular stimulation (using a battery-powered miniaturized stimulator, P-Stim) or with adhesive tapes instead of needles and no electrical stimulation (control group, CO, n = 30) at the auricular acupuncture points 29, 55 and 57. All patients received patient-controlled analgesia (PCA) with remifentanil. Pain intensity and psychological well-being were assessed by means of visual analogue scales (VAS); tiredness, nausea and vomiting and analgesic drug consumption were documented.

RESULTS

Pain relief and subjective well-being were significantly greater in group EA during and after the procedure as compared with groups A and CO (P < 0.001). The patients were significantly more tired in group CO than in groups A and EA (P < 0.001). Consumption of the opioid remifentanil was significantly lower in group EA, comparable nausea (P < 0.001).

CONCLUSION

Auricular EA significantly reduces pain intensity and analgesic consumption of the opioid remifentanil during oocyte aspiration in IVF treatment.

Anesthesia for in-vitro fertilization

PURPOSE OF REVIEW

To review the most recent literature on anesthesia for in-vitro fertilization.

RECENT FINDINGS

Very limited new information has become available in the review period. Propofol seems to be an acceptable option for anesthesia/sedation during in-vitro fertilization but more research is necessary to definitively establish its safety. Remifentanil is also an effective alternative.

SUMMARY

Presently, propofol and remifentanil seem to be acceptable options for anesthesia for in-vitro fertilization but further research is required.