"Unless conception occurred via in vitro fertilization, techniques used for obstetric dating are accurate to 3 to 5 days if applied in the first trimester, and only to 1 to 2 weeks subsequently. Estimates of fetal weight are accurate only to 15% to 20%. Even small discrepancies of 1 or 2 weeks between estimated and actual gestational age or 100 to 200g difference in birth weight may have implications for survival and long-term morbidity. Also, fetal weight can be misleading if there has been intrauterine growth restriction, and outcomes may be less predictable. These uncertainties underscore the importance of not making firm commitments about withholding or providing resuscitation until you have the opportunity to examine the baby after birth."
Textbook of Neonatal Resuscitation, 6th Edition, Ed J. Kattwinkel, American Academy of Pediatrics and American Heart Association (2011), p. 288
We cannot know when a person is supposed to die; neither can we predict exactly when a baby is to be born.
We have some numbers to play with and we do our best under the circumstances. Everyone knows that babies take nine months to grow in their mothers’ wombs. In the Jewish Talmud, it is stated that pregnancy should last 270 days from conception to birth. Modern Western medicine counts 40 weeks from the date of the last normal menstrual period, which gives a baby 38 weeks to mature, if his mother conceived fourteen days after her period. Many midwives will look carefully at a woman’s menstrual cycle, and will try to calculate together with the woman when she may have conceived. Based on these dates, she will give an estimate of a two or three week period during which the woman is likely to give birth. Some women give birth before their due dates, a few exactly on the day, and many give birth up to two or even three weeks after the date has passed. The tendency to carry a baby for over 41 weeks appears to run in families and can sometimes be predicted if a woman has carried her first child “post dates”.
One thing is for sure, babies do come out eventually. However, it is possible that certain risks increase the longer a baby stays in the womb. The placenta may diminish in optimal function after about 42 weeks, putting the fetus at risk for hypoxia. Babies born after 41 weeks often have a higher incidence of meconium in the amniotic fluid, which puts them at higher risk of meconium aspiration. Babies keep growing, so a 42-week baby may have a slightly larger head than she did at 38 weeks, thus making it a little harder for her mother to push her out. Modern medicine tries to diminish these risks by making sure a baby is born on or around the estimated date of delivery, or the due date. There is a lot of controversy about this reasoning, and rightly so. The due date is rather arbitrary. No one really knows when the baby was conceived, and even if they do analyze various ultrasounds, we can still never predict which babies will want to stay in the womb for longer. Occasionally there is a real problem with a baby which prevents the labor from starting spontaneously. This is very rare and does not justify the high induction rates we are seeing.
On |
Let us first have a look at some statistics, remembering that these numbers can be stretched and manipulated just like the perineum during birth. A recent study examined the correlation between labor induction and cesarean section. It looked at a reasonably small group of women (just over 1200) who were at 41 weeks of pregnancy. About half of these women went into labor spontaneously, and the other half was induced. The half who went into labor on their own had a 14% c-section rate, while the rate for the other half was 19%. The increased rate was due to an increase in c-sections performed for “failure to progress”, which was “diagnosed and cesarean delivery performed when cervical dilatation or fetal descent ceased for 2 to 4 hours despite adequate uterine activity”. However, the researchers concluded that the increase was not due to the labor induction “per se”, but rather due to “nulliparity, advanced gestational age, undilated cervix prior to labor, and epidural analgesia”.[i]
It seems to me that if we look at these figures with open eyes we can see that, in fact, induction is definitely an important player in the rise in c-section rates, even if we split hairs and suggest that it is not the main cause. Nulliparity certainly has an effect, and every doula knows that a first-time mother is going to be more of a challenge than a mother who has already gone through the experience. When a first-time mother experiences the contractions produced by synthetic oxytocin, she is much more likely to request an epidural than an experienced mother who knows that labor will, in fact, end and her child will be in her arms soon enough.
A woman with a closed, hard and posterior cervix is not an acceptable candidate for chemical induction. The rates of surgical delivery increase with a lower Bishop’s score. The following chart shows how we calculate this important score.
Score | Dilatation | Effacement | Station | Position | Consistency |
0 | 0 | <40% | -3 | posterior | firm |
1 | 1-2 cm | 40-50% | -2 | mid | moderately firm |
2 | 3-4 cm | 60-70% | -1,0 | anterior | soft |
3 | 5+ cm | 80%+ | +1,+2 | anterior | soft |
A point is added to the score for each of the following:
1. Preeclampsia
2. Each prior vaginal delivery
1. Preeclampsia
2. Each prior vaginal delivery
A point is subtracted from the score for:
1. Postdates pregnancy
2. Nulliparity
3. Premature or prolonged rupture of membranes
1. Postdates pregnancy
2. Nulliparity
3. Premature or prolonged rupture of membranes
The scoring is done according to the physician’s or midwife’s estimation of the cervix, and extra points are added or subtracted. Any score under 6 usually means that the cervix is not ready for induction and cervical “ripening” is initiated using prostaglandins. A score above 6 is encouraging and often means that a woman will be successfully induced and has more chance of a vaginal delivery. Induction leads to a higher epidural rate; epidurals lead to higher c-section rates: it is undeniable that labor induction can increase the risk of a c-section.
More serious is the situation where there is a perceived risk to the baby. In this situation, it is up to the doula to support her client and refrain from bringing doubts, research and opinions into the equation. If a doctor is convinced that, for example, the fluid is dangerously low, it is not the right time for a doula to suggest that perhaps this is physiologically normal or that the ultrasound technician could not see behind the fetus. This is the time for the doula to support her client wholeheartedly.
This is an example of the fine art of being a doula. We are not midwives, working from a rooted trust in the healthy efficiency of the female body. We are not physicians, sensitive to flaws and malfunctions in the labor process. We are there to support a woman through the labor process, as she sees fit, without judging, without voicing our opinion. Here is a story about an induction where the doula was very active in the whole process. This woman’s first labor had been chemically induced and she was hoping to avoid it the second time around.
[i] Obstet Gynecol 2001;97:911-915