Epidural drugs are administered usually over several hours via an epidural catheter, into the space around the spinal cord. These drugs include local anaesthetics which are all cocaine derivatives, e.g. bupivicaine/marcaine, more recently combined with low-dose opiates. Spinal pain relief involves a single dose of the same drugs injected through the coverings of the spinal cord and is usually short-acting unless given as a combined spinal-epidural (CSE). Epidural pain relief has major effects on all of the previously mentioned hormones of labour. Epidurals inhibit beta-endorphin production,(26) therefore inhibiting the shift in consciousness that is part of a normal labour. This could certainly be a reason why too many hospital staff are happy to encourage an epidural, because they are not prepared to deal with the irrationality and directness and physicality of a woman labouring on her own terms. Reduced staffing has no doubt influenced this also. When an epidural is in place, the oxytocin peak that occurs at birth is also inhibited because the stretch receptors of a birthing woman’s lower vagina, which trigger this peak, are numbed. This effect probably persists even when the epidural has worn off and sensation has returned, because the nerve fibners involved are smaller than the sensory nerves and therefore more sensitive to drug effects.(27)
A woman giving birth with an epidural will also miss out on the foetal ejection reflex, with its strong final contractions designed to birth her baby quickly and safely. She must then use her own effort, often against gravity, to compensate. This explains
the increased length of the second stage of labour and the increased need for forceps/ventouse when an epidural is used.(28)
Another hormone also appears to be adversely affected by epidurals. Prostaglandin F2 alpha helps to make a labouring woman’s uterus contractible, and levels increase when women labour without epidurals. In one study, women with epidurals experienced a decrease in PGF2 alpha, and average labour times were increased from 4.7 to 7.8 hours.(29) Drugs administered by epidural enter the mother’s bloodstream immediately and go straight to the baby at equal, and sometimes greater levels.(30,31) Some drugs will be preferentially taken up into the baby’s brain(32) and almost all will take longer to be eliminated from the baby’s immature system after the cord is cut. One research her found bupivacaine and its breakdown products in the circulation of babies for the first three days.(33)
Another indication of the effects of epidurals on mother and baby comes from French researchers who gave epidurals to labouring sheep(34). The ewes failed to display their normal mothering behaviour; This effect was especially marked for the ewes in their first lambing that were given epidurals early in labour. Seven out of eight of these mothers showed no interest in their offspring for at least 30 minutes.
Some studies indicate that this disturbance may apply to humans also. Mothers given epidurals in one study spent less time with their babies in hospital, in inverse proportion to the dose of drugs they received and the length of the second stage of labour(35). In another study, mothers who had epidural described their babies as more difficult to care for one month later.(36) Such subtle shifts in relationship and reciprocity may reflect hormonal dysfunctions and/or drug toxicity and/or the less-than-optimal circumstances that often accompany epidural births, i.e. long labours, forceps and caesareans.
There have been no good studies on the effects of epidurals on breastfeeding, although there is evidence that babies born after epidural have a diminished suckling reflex and capacity.(37,38) Certainly Midwives working on a post-natal ward observe all of the above. In fact these babies appear to be suffering the effects of opiates, in that they are sleepy and disinterested, in breastfeeding and their mother.