[Influence of the ovarian cycle on the central nervous system]

Influence of the Menstrual Cycle Phase on Pain Perception and Analgesic Requirements in Young Women Undergoing Gynecological Laparoscopy

CONTEXT

The influence of the gonadal hormones on some aspects of the human physiology has been studied with uncertain results. Still a confusion exists in relation to the real effects of the female hormones on the perception of pain. The existing data refer mainly to experimental studies and have provided results not always useful in the clinical practice.

DATA SOURCE

This study was designed to detect whether there are differences in the perception of the postoperative pain in women, during two clearly defined phases of hormonal asset: luteal and follicular phases.

CONCLUSION

The results of this study have demonstrated that in postoperative female patients pain is perceived significantly more in the luteal phase of the menstrual period, than in the follicular phase. This could suggest that female in child-bearing age should be scheduled for elective surgery preferentially during the follicular phase, unless differently necessary. It would guarantee a more comfortable postoperative period, with reduced necessity of analgesics.

Effects of the menstrual cycle on injection pain due to rocuronium

STUDY OBJECTIVE

To investigate the effect of the menstrual cycle on rocuronium injection pain.

DESIGN

Prospective, randomized, double-blinded study.

SETTING

Academic medical center.

PATIENTS

80 ASA physical status 1 and 2 women scheduled for elective surgery with general anesthesia.

MEASUREMENTS

Patients were divided into two groups according to their time in the menstrual cycle. Forty patients at days 8 to 12 of the menstrual cycle were considered to be at the follicular phase (Group F), and 40 patients at days 20 to 24 of the menstrual cycle were considered to be at the luteal phase (Group L).Withdrawal movements were recorded.

MAIN RESULTS

Overall frequency of withdrawal movements was significantly higher in Group L than Group F (P < 0.001). The mean withdrawal movement score was 1.77 ± 0.76 in Group L and 0.52 ± 0.67 in Group F.

CONCLUSION

Menstrual cycle phases affect the severity of rocuronium injection pain. Women exhibit greater pain sensitivity from rocuronium injection in the luteal phase than the follicular phase.

Age-related changes in the oestrous cycle and reproductive hormones in senescence-accelerated mouse

To investigate age-related changes in the oestrous cycle and reproductive hormone levels in senescence-accelerated mouse (SAM), we examined these parameters in 3-, 5-, 7-, 9- and 11-month-old female SAM-prone/8 (SAMP8) and SAM-resistant/1 (SAMR1) strains. Levels of beta-endorphin (beta-EP) and substance P (SP) in the hypothalamus were also measured. The oestrous cycle and dioestrus of 9-month-old SAMP8 mice were significantly prolonged compared with age-matched SAMR1 mice. Furthermore, the concentration of serum oestradiol was lower and the level of pituitary luteinising hormone was higher in SAMP8 mice compared with SAMR1 mice. This characterises the hypothalamus-pituitary-ovary (HPO) axis of the SAMP8 strain as hypergonadotropic-hypogonad. The levels of beta-EP and SP in the SAMP8 hypothalamus were lower than in the SAMR1 hypothalamus. These results indicate that the function of the HPO axis in SAMP8 mice declines early and this may be attributed, in part, to the decline in beta-EP and SP concentrations in the hypothalamus.