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Drugs in Labour: What Effects Do They Have 20 Years Hence?
by Beverley Lawrence Beech
© 1999 Midwifery Today, Inc. All Rights Reserved.
[Editor's note: This paper was presented at the Midwives of North America (MANA)
Conference in November 1998, and appeared in Midwifery Today Issue 50, Summer 1999.]
Childbirth is a normal physiological event. However, since the advent
of universal hospitalisation, for the majority of women childbirth has
been transformed into a medical event where labour is processed, monitored
and controlled by the medical profession from beginning to end.
Although childbirth propaganda promotes the normality of birth, few
women giving birth in large centralised medical establishments will experience
a normal birth. Instead, they will find themselves and their babies subjected
to a whole range of powerful drugs.
Although women allegedly give informed consent for the use of those
drugs, the reality is that the majority of women have little information
about drugs in labour. The propaganda promotes the "advantages"
of drug use, but little is said about the disadvantages, particularly
the long-term effects. It is those effects that I would like to examine.
All drugs have unwanted effects, some more serious than others. In the
1950s and 1960s thousands of babies all over the world were born with
severe limb abnormalities as a direct result of their mothers taking thalidomide
during pregnancy. It took 10 years for researchers to establish
thalidomide was to blame, while the medical profession and drug
companies vigorously denied any connection.
During the 1940s and 1950s the hormone diethylstilboestrol (DES) was
used on pregnant women in the belief it could prevent miscarriage.
Unfortunately, it was widely adopted—particularly in the United States—before
any randomised clinical trial was done to show whether it was effective.
When such a trial was eventually done, the drug was shown not to work.
Nonetheless, some doctors continued to use it. The time bomb effect came
to light when a cluster of young women in one town developed an unusual
form of cancer: clear cell carcinoma of the vagina. Had they developed
a more common cancer—squamous cell cancer of the cervix, for example—the
link would not have been made. They also had other problems, such as abnormalities
of the genital tract. However, more subtle difficulties were discovered
only when British researchers (Vassey et al., 1983) studied the now grownup
offspring of women who had been involved in a randomised clinical trial
in which half were given stilboestrol when pregnant, with the other half
serving as controls. Exposed children were significantly more likely to
have serious mental illness, and boys were less likely to have married.
Furthermore, 40 percent to 50 percent of DES-exposed daughters had pronounced
uterine structural abnormalities. Infertility was reported among the women
and diminished fertility among the men.
More than four to eight times as many of the DES-exposed children as the unexposed went
on to have tubal pregnancies. A quarter of all pregnancies
among the DES-exposed children went on to miscarry, compared with the normal
10 percent rate. Premature birth occurred in three times as many babies.
For DES-exposed sons, nearly a third had testicular abnormalities that
decrease male fertility, including undescended testes, sperm abnormalities
and low sperm counts. It would appear that many of the non-physical, but
serious, adverse effects would not have been identified except for the
fact that exposed girls had developed a particularly unusual cancer. In
the United States, the granddaughters of women given stilboestrol in pregnancy
are now suing for injuries they suffered because of alleged stilboestrol-induced
abnormalities in the genital tracts of their mothers, who were exposed
in the womb. This is an example of how damage may be transmitted from
generation to generation. Therefore, one would expect the medical profession
to be particularly careful about using drugs in pregnancy and labour.
One of the most common drugs used in the labour ward is pethidine, a
synthetic, addictive, narcotic drug that is similar to morphine. In Britain
it is also known as meperidine, and in America it is known as Demerol. It has become
the drug of first choice for the majority of UK midwives, mainly because
it is the only pharmacological narcotic they are licensed to prescribe.
Commonly, women are given a dose of 150 mg, yet those midwives who
use Demerol sparingly often give a much smaller dose—25 mg, for example—
and claim it is just as effective.
Demerol readily crosses the placenta. The baby may have greater sensitivity
to the drug because of the immaturity of the blood-brain barrier and the
circulatory bypass of the liver (Burt,1971). If the baby is expected to
be born within an hour, most midwives try to ensure that Demerol is not
given because of the risk that the drug will be present in the baby. However,
research shows that Demerol is most likely to have a depressant effect
on the fetal respiratory system if the dose is administered two or three
hours before birth. The higher the dose to the mother, the greater the
effect on the fetus (Yerby, 1996). Because the baby's liver is immature,
it takes a great deal longer—18 to 23 hours—to
eliminate the drug from its system.
Although 95 percent of the drug is excreted in two to three days, this
can have significant implications for breastfeeding. Rajan demonstrated
that "Demerol proved to be the (drug) most inhibiting to breastfeeding."
By breastfeeding, the mother often unknowingly gives the baby a second
dose of Demerol, as the drug is transferred to the baby through the breast milk.
She may not be aware that Demerol is the cause of her "sleepy"
baby and her problems with getting the baby latched on.
Little research has been done into the long-term effects of Demerol.
However, infants with high Demerol exposure were more likely to cry when
handled on days seven, 21 and 42, as were those with a
high cord-blood concentration on day 21. Demerol also reduced
the infant's ability to quiet himself once aroused. This was still observed
at three and six weeks (Belsey, 1981). It is interesting that researchers
consider three to six weeks to be "long-term." Our definition
would be in years.
For those babies whose breathing is depressed at delivery, naloxone is
given to reverse the effects, but the reversal is only temporary unless
it is given in an adult dose (Weiner, 1977). We know of no research that
investigates the short- or long-term effects of naloxone on the baby.
The Pain of Labour
A consistent criticism Association for Improvements in the Maternity
Services (AIMS) members make of obstetrically managed births is that there
is pressure to deliver all babies as quickly as possible, as if this were
a benefit to both mother and baby. We know of no study that asked women
whether they wanted a faster, but more painful, labour.
It is extremely difficult to assess the level of pain a woman is experiencing;
different women react in different ways. Interestingly, when a woman fails
to experience pain relief from Demerol or other drugs, she will often
be told that she has a "low pain threshold." I have yet to hear
the problems described as a failure of the drug to act effectively. In
a survey of pain relief in childbirth (Chamberlain, 1993) 84 percent of
midwives rated Demerol as very good or good, compared with only 71 percent
of women and 72 percent of partners. The authors speculated: "Perhaps
the drowsiness of the woman following the administration of pethidine
(Demerol) is associated with effective pain relief by the midwife."
From the woman's perspective Demerol has been described as causing a loss
of control, disorientation and dizziness. As one mother described it:
"I felt that my brain had gone out to lunch. I could not put a sentence
together, but it did nothing for the pain—it just shut me up."
Women who end up with caesarean sections have often experienced induced
or accelerated labours, and Demerol is often one of the many drugs they
have been given during that time. However, Demerol delays maternal gastric
emptying and, in concert with sedation, increases the risk of aspiration
and thus the danger of general anaesthetic (Olofsson, 1997).
Chamberlain's Study Pain
and Its Relief in Childbirth found that Demerol appeared last on a
list associated with enjoyment of labour, being in control of labour and
delivery, and physical and mental health afterward. Demerol was unlikely
to be wanted for future delivery and was most strongly associated with
problems in the baby, such as side effects, temperament and feeding difficulties.
It gave low satisfaction for pain in labour—and especially pain during
delivery—was associated with poor physical and mental health in the mother
after delivery, and had a fairly low rating for enjoyment of labour and
Instead of urging non-pharmacological methods of pain relief (for example,
water pools), the latest research paper to reveal the inadequacy of Demerol's
pain-relieving effects suggests that epidural anaesthesia should now be
widely available (Olofsson, 1996). The authors have few worries about
the adverse effects of this drug.
In 1981 Rosenblatt published a six-week follow-up of the effects of
epidural anaesthesia, which showed that immediately after delivery, infants
with greater exposure to bupivacaine in utero were most likely to be cyanotic
and unresponsive to their surroundings. Visual skills and alertness decreased
significantly with increases in the cord-blood concentration of bupivacaine,
particularly on the first day of life but also throughout the next six
weeks. Adverse effects of bupivacaine levels on the infants motor
organisation, his ability to control his own state of consciousness and
his physiological response to stress were also observed. Interestingly,
this study considered six weeks to be "long-term," but what
are the long-term effects at 5, 10, 20 or 50 years?
Women who choose water for pain relief have been warned that a rise
in the water temperature over 37° C could cause a rise in the mother's
temperature and result in brain damage in the babies, with no research
evidence whatsoever to support that suggestion. As a result, many UK hospitals
have refused women access to water pools. However, research by Lieberman
(1997) revealed that intrapartum fever greater than 100.4° F occurred in
14.5 percent of women receiving an epidural. If the labours lasted longer
than 18 hours the rate increased to 36 percent. Not a single
paediatrician has expressed concern about this risk.
In her submission to the Food and Drug Administration (FDA), Yvonne
Brackbrill commented that at that time there had been at least 40 studies
of neurobehavioural changes in human infants that were observed after
administration of anaesthetic and pre-anaesthetic agents to their mothers
during labour and delivery. "None has shown that drugs enhance or
improve behavioural functioning in infants," she wrote (Brackbrill,
In the human being, the period of vulnerability to central nervous system
damage from exposure to drugs and chemicals lasts a long time. Even after
birth, important areas of the brain are still developing and differentiating
at a very rapid rate, and because of this rapid period of growth they
are maximally vulnerable to damage. It has been estimated, for example,
that the brain growth spurt in the cerebellum lasts for 18 months
after birth and in the hippocampus for about four and one-half years.
Some parts of the brain are fairly well developed at the time a human
being is born, but other parts are not. Some parts, particularly the cerebellum,
are very underdeveloped; and the introduction of toxic substances during
this period of rapid development, even for a single acute administration,
can either kill cells or cause aberrations in them. When cells proliferate
in the cerebellum, thats not the end of it—they have to migrate
into their final position and link up with other cells. Both the rate
of cell death and the patterns of migration of cells in the cerebellum
have been shown to be very sensitive to the introduction of toxic substances
Desmond Bardon, a respected British psychiatrist, asked what prolonged
exposure to maternally administered drugs means to the later neurologic
development and behaviour of the offspring. Drug-induced biochemical alterations
within the brain of the about-to-be-born or newly born infant have the
potential for permanently disrupting the normal link-up of the baby's
brain cells by altering the biochemical markers that guide the cells
into their proper places. It is somewhat analogous to the unintentional
spilling of a chemical over telephone wires that are being connected according
to the colour code at the end of each wire. The chemical removes the colour
from the wire ends. The technician must continue to connect the wires,
not knowing exactly which wires to connect with what. The circuitry is
completed: It functions, but imperfectly.
While the process of cell migration is not yet fully understood, present
knowledge of neurobiology suggests that the normal biochemical message
left along the pathway of the neuron by the preceding cell (as it travels
to its proper place within the central nervous system) serves to direct
the next brain cell into place. Drug-induced changes in the biochemical
message can disrupt this vital process. Could dyslexia be the result?
In the developed world there is an epidemic of dyslexia, drug addiction
and behavioural problems. I suggest that one of the reasons for this
is the overuse of powerful drugs in labour.
I find the hypocrisy about drug use quite astonishing. In the United
States, it appears that women who smoke or drink alcohol in pregnancy
can be publicly chastised; if they take heroin, or other street drugs,
they can find themselves in jail or threatened with removal of the baby
and their other children. But no one raises even a murmur about the far
more powerful addictive drugs that are used on the labour ward, and no
one appears concerned about the effects these drugs can have on a still-developing fetal brain.
There are plenty of studies examining the immediate effects of drugs
in labour, but where are the studies examining the long-term effects?
By that I mean effects that can emerge, 5, 10, 20 or even 50
I suggest we are sitting on a time bomb, and we persist in ignoring
the research because of the horrendous implications. No one wants to admit
that their care is creating drug addicts, but I believe the overuse of
drugs in pregnancy and childbirth is doing just that.
In a well-designed case control study at the Karolinska Institute in
Stockholm in 1990, researchers compared children exposed to pain-relieving
drugs in labour with those who were not exposed and discovered an increased risk
of drug addiction later in life (Jacobson et al., 1990). In 1988 they
showed that when nitrous oxide was given to the mother the child was five
and one-half times more likely to become an amphetamine addict than a brother
or sister born to the same parents. In their paper in the British Medical
Journal(1990), patients who had died from opiate addiction were compared
with brothers and sisters; the researchers found that if the mothers had
been given opiates or barbiturates or larger doses of nitrous oxide, the
risk to the child of opiate addiction in later life was increased 4.7
times. In a further study, researchers discovered that the risk of drug
addiction was related to the hospital in which they were born. In other
words, the likelihood of a child developing drug addiction in later life
depended on the labour ward policies of the hospital the mother chose
for the birth, and I quote: "For the amphetamine addicts, hospital
of birth was found to be an important risk factor even after controlling
for residential area" (Nyberg, 1993). Jacobson and Nybergs
research suggests that the use of opiates, barbiturates and nitrous oxide
in labour causes imprinting in the babies, and we are now reaping the
The U.S. Department of Health and Human Services estimated that one
out of every nine American children is significantly learning disabled
despite having normal intelligence. Seventy-five percent of these children
are born at full term into middle- and upper-class families. The U.S. National
Institute of Health estimates that 75 percent to 85 percent of all disabled
children in the United States were born within the normal range of birth
weight and gestational age and had no familial or sociologic predisposing
factors (Haire, 1989).
In 1984, Desmond Bardon suggested that a significant proportion of the
millions of children and youths in the United States who are afflicted
with significant mental and neurologic dysfunction are the victims of
obstetric medications administered with the very best of intentions to
the mother during labour and birth in medicalised maternity units. Not
only have Bardons concerns not been addressed, but since that time
even more women and babies have been subjected to high levels of drugs in pregnancy
and labour, and little has been done to investigate the possibility that
the huge increases in drug addiction and associated crime are a direct
result of the drugs used on the labour wards. While various agencies work
hard to pull the bodies out of the river, no one is investigating who
is pushing them in upstream. It is time they did.
Beverley A. Lawrence Beech, honourary chairwoman of the Association for Improvements
in the Maternity Services (AIMS), is a freelance writer and lecturer and
lives in the United Kingdom.
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presented at the conference Obstetrical Management and Infant Outcome arranged by
the American Foundation for Maternal and Child Health, New York.
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and delivery on breast feeding. Midwifery, 10(2): 87-103.
- Rosenblatt, D. B. et al. (1981).The influence of maternal analgesia on neonatal
behaviour: 11 Epidural bupivacaine. British Journal of Obstetrics and Gynaecology,
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