Catecholamine and cortisol reaction to childbirth

One way to study the stressfulness of childbirth is to examine the output o f stress hormones. In this study, urinary catecholamines and salivary corti sol from 50 primiparous women were collected for 1 day during gestational w eeks 37 to 39, hourly during labor and delivery, and 2 hr and 2 days postpa rtum. All three stress hormones increased statistically significantly from pregnancy to labor. The increase in adrenaline and cortisol was more than 5 00%, and the increase in noradrenaline was about 50%. After labor, the outp ut decreased but not statistically significantly below the levels during la te pregnancy. Hormone levels during late pregnancy, during labor and delive ry, and during the period postpartum mostly did not correlate systematicall y. However, noradrenaline and adrenaline, as well as adrenaline and cortiso l, were positively correlated during labor. After administration of epidura l analgesia, there was a moderate but significant decrease in noradrenaline and adrenaline, whereas cortisol did not change. In conclusion, the result s of this study support the assumption that childbirth is a very stressful event and that the stress responses vary considerably among women. The subs tantial increase of adrenaline and cortisol compared with noradrenaline ind icates that mental stress is more dominant than physical stress during labo r.