Effects of Patients' Hormone Levels on Sedoanalgesia

In anaesthesia practice, the need for anaesthetic agents can be affected by many different factors. These factors may include age, gender, body weight, existing hepatic or renal insufficiency, cardiovascular diseases, low ejection fraction, and some hormonal changes may also be effective in the need for anaesthetic agents. For example, there are studies showing that progesterone, which increases in the last period of pregnancy in pregnant women, decreases the use of anaesthetic agents due to its central effects. In a study by, the MAC level of sevoflurane was measured by following the haemodynamic data and bispectral indexes of the patients and the amount of sevoflurane used was found to be less in patients with higher serum progesterone levels in pregnant women with gestational pregnancies older than 36 weeks undergoing planned cesarean section.

Estrogen and progesterone ratios regulate gonadotropin secretion and sexual behaviour in the brain. In addition, although it is known to be effective in analgesia and pain sensation pathways, this mechanism has not yet been fully understood . In an experimental animal study, it was concluded that estrogen facilitates pain transmission in acute pain pathways. In an animal study conducted in female rats, the need for anaesthetic agent in anaesthesia practice can be affected by many different factors at different times of the menstrual cycle phases. These factors may include age, gender, body weight, existing hepatic or renal insufficiency, cardiovascular diseases, low ejection fraction, and some hormonal changes may also be effective in the need for anaesthetic agents. For example, there are studies showing that progesterone, which increases in the last period of pregnancy in pregnant women, decreases the use of anaesthetic agents due to its central effects. In a study, the MAC level of sevoflurane was measured by following the haemodynamic data and bispectral indexes of the patients and the amount of sevoflurane used was found to be less in patients with higher serum progesterone levels in pregnant women with gestational pregnancies older than 36 weeks undergoing planned cesarean section.

Estrogen and progesterone ratios regulate gonadotropin secretion and sexual behaviour in the brain. In addition, although it is known to be effective in analgesia and pain sensation pathways, this mechanism has not yet been fully understood. In an experimental animal study, it was concluded that estrogen facilitates pain transmission in acute pain pathways. In an animal study in female rats, it was concluded that the characteristics of mu receptors in the brain changed in relation with the amounts of estrogen and progesterone secretion at different times of menstrual cycle phases. There are many publications in the literature examining the effects of estrogen and progesterone on analgesia pathways.

In today's anaesthesia practice, we encounter a large number of female patients both in operation theatres and in daily anaesthesia. In the process of in vitro fertilisation treatments, which is one of these areas, the need for daily anaesthesia arises for many procedures. Especially oocyte collection is performed with sedational procedures. Before the oocyte collection procedure, various hormone supplements are administered to the patients to ensure oocyte maturation, and patients who are shown to have reached adequate hormone levels in the laboratory with pre-procedure USG examination are taken to the oocyte collection procedure for aspiration of the follicles formed. This procedure requires a level of sedation in which patients can be immobilised and painless.

Investigastors hypothesis is that the need for anaesthetic agents is less in patients with high progesterone levels and more in patients with high estrogen levels.

The investigators' plan in this study is to examine the correlations of progesterone level, estrogen level, progesterone/estrogen level parameters with anaesthetic agent consumption via 3 groups

Inclusion criteria

• Between 18-45 years old
• ASA-I ASA-II patients who were sedated for oocyte pick-up between 1 June 2025 and 1 September 2025 at Izmir City Hospital
• Patients whose hormone levels were measured in the preoperative period due to surgical indication and registered in the hospital data processing system

Exclusion criteria

• Lack of patient approvel
• Diagnosed psychiatric disorder
• Use of drugs affecting the central nervous system
• Presence of chronic pain syndrome
• History of continuous analgesic use due to chronic pain
• Hepatic and/or renal insufficiency
• BMI>30
• Changing the method of anaesthesia for any reason