Endocrine changes at operation under general anesthesia: reproductive hormone fluctuations in young women.

This study investigated changes in peripheral serum estrogen (E), Progesterone (P), luteinizing hormone (LH), follicle-stimulating hormone, and prolactin (PRL) in 11 women of reproductive age undergoing a variety of operations under general anesthesia without compromise of ovarian vasculature. All hormone determinations were plotted in relation to the midcycle LH peak; eight women with cyclic ovulatory menses served as controls. The absolute value of E declined after surgery but did not reach statistical significance. P levels postoperatively were significantly lower following ovulation (P less than 0.01) on cycle days +1 through +5. Intraoperative and postoperative PRL values were significantly greater than those of control subjects (P less than 0.05). Aside from a transient intraoperative decline in LH, the pattern of gonadotropin secretion was similar to that of control subjects. The decline in peripheral ovarian steroid levels appeared to be independent of abdominal entry or pelvic manipulation. The evidence favors direct inhibition of ovarian steroidogenesis by (1) toxic effects of anesthetic agents or (2) stress-induced changes in other hormone levels, e.g., hyperprolactinemia.