- Email: [email protected]
Postmaturity Babies
Postmaturity Babies From the Department of Obstetrics and gynecology, University of California School of Medicine, San Francisco
PHILIP H. ARNOT, M.D., F.A.C.S. Emeritus Clinical Professor of Obstetrics and Gynecology, Um:versity of California School of Medicine; Staff, St. Mary's Hospital
DONALD R. NELSON, M.D., F.A.C.S. Associate Clinical Professor of Obstetrics and Gynecology, University of California School of Medicine; Staff, St. Mary's Hospital
MucH INTEREST has been evident during the last few years in the subject of postmaturity and postmature babies and several articles have appeared in the medical literature on the subject. The term is not a good one as it infers that all babies that remain in utero for 294 or more days, or two weeks more than the·usually figured 280 days, are postmature. The vast majority of such "late" pregnancies are really miscalculations or postdate, overtime, overterm or prolonged pregnancies, to use other terms. We believe, however, that a very few are truly postmature even though it is very difficult or impossible to prove it. The determination of the expected date of confinement is only approximate and the magic number of 280 days as the duration or length of pregnancy has been handed down to us by the people of ancient ages. Centuries ago when the physicians were magicians they sought to explain the onset of labor by happenings or changes of the moon and stars. They came to associate menstruation as something that happened with every full moon, that is, every 28 days. They caJculated that a baby would be carried in utero for ten moon months (280 days) and would be born at the tenfold of the moon, which would also be the tenfold of the menstrual cycle. Thus the folklore of babies being born at the time of a full moon has persisted to the present time. While at Heidelberg, Naegele came forth with his short, rapid method of figuring the expected date of confinement by advising that one count
895
896
PHILIP
H.
ARNOT, DoNALD
R.
NELSON
back three months from the last period and add 7 days. He overlooked the fact that periods do not always occur every 28 days, are often irregular and, furthermore, he did not :my whether to count from the start or end of the menstrual period. Also, there are 12 possible combinations of nine consecutive months and, by subtracting three months and then adding seven days, one gets 280 days seven times, 281 days and 282 days twice, and 283 days once. Most physicians figure from the start of the period in using Naegele's rule and we have always used it in this manner. In 1942 one of us (P.H.A.) went over the records of 3606 private patients for the delivery dates and found that 53.5 per cent were late or went overtime and 42.4 per cent were early or ahead. of time as determined by Naegele's rule, for the same average of 10.2 days. The time of ovulation may also vary considerably in the same individual even though she may menstruate fairly regularly on a 27 to 30 day cycle. So we can see that even if a woman is absolutely sure of her last period and the intervals between the previous ones for a year or more, there is still apt to be considerable error in reckoning the actual duration of the pregnancy because we so seldom know the exact date of conception. Behind this new interest in postmaturity or postdatism is the fact that a certain percentage of postmature babies die during or before labor and in the neonatal period and the question naturally arises as to why they died and how we could have prevented the deaths. Their mothers are patients with perfectly normal prenatal courses and no evidence of toxemia, bleeding, infection or other complications that might be dangerous to the fetus. The first natural question is whether or not these fetal deaths could be due to changes in placental function. There is apparently a placental senescence that sets in or starts about the time of or after term, which might be a factor. Some feel that there is a relative placental insufficiency which could account for this difficulty and that it may occur before term as well as in the patients who go beyond their due date. In a personal communication Nesbitt, in September 1958, said that he does not believe that the problem of postdate pregnancy or postmaturity is chiefly one of progressive placental dysfunction as the pregnancy proceeds beyond term. It seems to be a complex problem characterized by a combination of factors which reduce placental reserve. These patients have larger babies, more abnormal presentations and longer and more difficult labors than do patients delivered at term or under. He feels that there are fetal and uterine as well as placental factors involved in the whole problem. In his experience the preponder-
Postmaturity Babies
897
ance of fetal deaths occurred during labor, usually in association with one or more complicating factors. He finds considerable experimental evidence, such as oxygen gradients across the placental barrier and cord blood studies, to show that postmature pregnancies, uncomplicated by toxemia or difficult labors, maintain a placental function comparable to that noted in mature pregnancies. He has not been able to demonstrate a precise correlation between cord blood counts and gestational age beyond term as Walker reported in 1954 and these data support his clinical impression that the uncomplicated patient who goes beyond term has a good prognosis for the fetus. He feels that the potential hazards to the fetus are principally during labor when more complications occur. Walker and Turnbull in 1953 investigated the hemoglobin and red blood cell content of the fetus at birth and found that the hemoglobin tends to rise from 16.5 gm. at birth (term) to 18.8 gm. at 43 weeks, and Walker in 1954 suggested that this rise in hemoglobin and also in red cell counts is in response to the fall in the oxygen saturation in cord blood that takes place as the pregnancy is prolonged beyond term-a sort of compensatory mechanism. Bancroft-Livingston's and 0. D. Fisher's work in 1958 failed to support the view of Walker that prolongation of pregnancy is associated with hypoxia and, therefore, with a rise in the hemoglobin level, whether the fetus does or does not exhibit clinical evidence of distress before delivery. Clifford believes that there is definitely such a thing as postmaturity and refers to it as "the postmaturity with placental dysfunction." In order for a baby to be classified as postmature, he feels that the pregnancy should be prolonged to 20 days or more beyond the expected date of confinement-that is, 300 or more days of gestation as figured from the beginning of the last period. Clifford divided the babies into three groups or stages as follows. Stage one: There is a loss of vernix from the skin and evidence of malnutrition but the skin is unstained. Stage two: Same findings as in stage one plus a green meconium staining of the amniotic fluid and of the baby's skin, cord and the membranes. Stage three: Evidence of malnutrition may be more severe and the skin, fingernails and cord are stained yellow. PLACENTAL PATHOLOGY
Wislocki and Dempsey demonstrated the aging process of the placenta by means of histochemical studies. They found acid phosphatase in the trophoblastic syncytium only toward the end of gestation whereas
898
PHILIP
H.
ARNO'I', DoNALD
R.
NELSON
alkaline phosphatase was found in the placenta early in pregnancy and increased until term. Strand found age changes starting in the placenta around the seventh month. These changes showed the stroma in the chorionic villi becoming more fibrous and the vascular villi thickened by endarteritis and periarteritis. Syncytium overlying the villi becomes more atrophic and thinner in some areas and fibrin is deposited slowly. Some of the villi degenerate and white infarcts are found as in every mature or term placenta. There are calcareous areas on the maternal surface of the placenta and these are more common on the mature and postmature placentas. Kloosterman found that the average weight of placentas of postmature infants who were born dead or died was 450 gm. as opposed to 535 gm. in those postmaturity infants who were born alive. The placentas of the dead babies showed more infarctions than those of the live babies. Masters and Clayton found that the calcium content of the placentas was very low before the thirty-eighth week of pregnancy and increased in a variable way as term and postmaturity were reached but was generally higher in the postmature pregnancies. They felt that the degree of calcification was an index of the degree of villous degeneration, although villi may degenerate without becoming calcified. In a study correlating radioactive sodium transfer curves with ·the morphologic changes which occur in the placenta during aging, Flexner and his group found a steady increase in placental permeability by the thirty-sixth week, after which there was a marked decrease. This was interpreted as being due to the deposition of fibrin over the surface of the villus. Nesbitt states that he has not been able to demonstrate a placental lesion, either gross or microscopic, which can be considered characteristic and peculiar to postmature pregnancy. He has, however, demonstrated pathologic lesions in the placentas of postmature pregnancies, such as calcification, infarctions of various types, and .areas of disruption and infection. However, he finds these same lesions in placentas of patients who deliver at the regular expected date. He also found that the placentas were larger in postmature pregnancies. In examining nearly 1000 placentas of postdate pregnancies, Nesbitt has not seen objective evidence of excessive aging above that seen in mature pregnancies. He emphasizes, however, that normal structure does not mean the function is also normal. In trying to form some conclusions from what has been written on the subject, we find that most investigators are of the opinion that there are actually few cases of real postmaturity; that they are mostly postdate pregnancies and that, even if there is a slight increase in the fetal mor-
899
Postmaturity Babies
tality in such cases, one should do nothing about it, allow labor to start of its own accord and not induce labor. Many of them believe that the risk of fetal death is greater from induction of labor than from the results of postmaturity and decreased function of the placenta due to its senescence. Others feel that labor should be induced. There seems to be no characteristic, pathognomonic placental lesion of postmaturity but most investigators have found pathological lesions in the placentas of these pregnancies. Our Own Experience
We became interested in this subject in 1957 and 1958 and reviewed our deliveries up to July 1, 1958. We have now reviewed our cases up to December 1, 1961 and present our data and conclusions here. We have had 13,776 private deliveries between July 1, 1922 and December 1, 1961, 779 (5.65 per cent) of which were 14 or more days beyond the expected date of confinement. There were 409 first pregnancies and 370 multiparous pregnancies in this postdate group. Additionally, there were over 100 other pregnancies that were possibly late by 14 or more days but these are not included because of the irregularity of the periods or because the patients were not absolutely certain of their last periods. Table 1 shows the number and percentage of primiparas and multiparas who went overtime as figured by intervals of seven days or weekly Table 1.
Duration of Pregnancy in Weeks and Days
294-300
301-307
308-314
315-321
Days
Days
Days
Days
Days
42-43
43-44
44-45
45-46
46-47
Weeks
Weeks
Weeks
Weeks
Weeks
89 21.5
19 4.64
3
78 21
10 2.7
4 1.08
322-328
Primiparas Number of cases ... 297 Percentage ... ......... 72.6
1 .24
.73
Multiparas Number of cases .... Percentage ........
277 74.8
1 .27
intervals. One sees that about 72 per cent of the primiparas were from 14 to 20 days late (two to three weeks) and that 74.8 per cent of the multiparas were two to three weeks late. Approximately 21 per cent of each group went overtime or past term by 21 to 27 days or three to four weeks. Only a few went over 28 days or four weeks. As to the presentations of the babies, Table 2 shows the number and
900
PHILIP
Table 2.
H.
ARNOT, DONALD
R.
NELSON
Position of Baby
PRIMIPARAS
MULTIPARAS
Number Percentage
Number Percentage
L.O.A ............... 194 R.O.P ............... 91 R.O.A ............... 68 L.O.P ............... 26 L.S.A ............... 11 R.S.A ............... 7 L.S.P ............... 4 R.S.P ............... 1 R.B.A ............... 3 R.M.P .............. 2 L.M.P .............. 0 L.M.A .............. 1 Transverse .......... 1
47.4 22.2 16.6 6.35 2.68 1.7 .97 .24 .73 .48 0 .24 .24
180 62 83 21 4 16 0 1 2 0 1 0 0
48.6 16.7 22.4 5.6 1.08 4.32 0 .27 .54 0 .27 0 0
percentage in each category. The left occiput anterior (L.O.A.) position occurred in approximately 48 per cent of each group; the right occiput positions (R.O.P. and R.O.A.) in about 38 per cent of both, the R.O.P. being slightly more prevalent than R.O.A. in the primiparas while the R.O.A. position was more prevalent than R.O.P. in the multiparas, by the same percentage. Then came L.O.P., 6.35 per cent in the primiparas and 5.67 per cent in the multiparas. There were then a few breech, brow and face presentations in each group and one transverse in a primipara. Most people have the idea that post.mature babies are preponderantly larger than term babies. That. has not. been found in our series. As seen in Table 3, 77 (19.2 per cent) of the babies of primiparous mothers and 42 (11.4 per cent) of the babies of multiparas were between 5 to 7 pounds; 144 (36 per cent) and 110 (29.8 per cent) respectively Table 3. Pounds ................. 5-7 ........... 2300 to Grams .... 3200
Baby Weights
7-8 3201 to 3650
8-9 3651 to 4950
9-10 4096 to 4553
10-11 4554 to 5000
11-12 5001 +
Primiparas Number of cases ....... 77 19.2 Percentage ......
144 36
107 26.7
59 14.2
11 2.77
2
Multiparas Number of cases ....... 42 Percentage ............ 11.4
110 29.8
147 39.9
55 14.9
12 3.26
2
.5
.54
Postmaturity Babies
901
were 7 to 8 pounds; 107 (26.7 per cent) and 147 (39.9 per cent) were 8 to 9 pounds; 59 (14.2 per cent) and 55 (14.9 per cent) were 9 to 10 pounds and 11 (2.77 per cent) and 12 (3.26 per cent) were 10 to 11 pounds. There were only two babies in each group who weighed between 11 to 12 pounds. If one considers only the babies weighing 8 to 12 pounds, we find that 48.1 per cent (about half) of the primiparas and 58.6 per cent (about six out of ten) of the multiparas had what we can call big babies. With 50 to 60 per cent of the babies classified as "large" we could expect that many of these mothers would have long or prolonged labors and more difficult deliveries, with an increased incidence of forceps and cesarean deliveries, at least in the primiparas. Twenty-two per cent of our primiparous mothers had labors of 24 hours or more, which is a larger percentage of long labors than occurred in each of two groups of term primiparas that we reviewed. These were a group of patients with occiput posterior presentations who had 24 hours or more of labor in 17.6 per cent and another group with occiput anterior presentations who had similar prolonged labors in 5.04 per cent. So we must conclude that these longer labors are caused by bigger babies which, in turn, are large because of their postmaturity or postdatism. The methods of delivery are shown in Table 4. The spontaneous Table 4.
Method of Delivery
SPONTANEOUS
CESFORCEPS
BREECH
Primiparas Number of cases ... 177 Percentage ........ 42.2
184 44.9
28 6.84
Multiparas Number of cases ... 312 Percentage ........ 84.3
42 11.3
Av=<' Percentage of ) ... 63.7 Primiparas and
28.1
AREAN
27 6.6
2.95
5 1.35
4.89
3.97
11
VERSION AND EXTRACTION SCANZONI
1
1 .25
0 0
.25 0 0
.24
.24
Multiparas
deliveries in both primiparas and multiparas are less than our general average and the forceps and cesarean deliveries are increased in the primiparas over our general average. We believe that, just as prolonged labors are due to these big babies, the increase in forceps and cesarean deliveries, in the primiparas, is due to the same reason.
902
PHILIP
Table 5.
H.
ARNOT, DONALD
R.
NELSON
Comparative Data PRIMIPARAS
MULTIPARAS
Table 5 shows the number of patients in whom labor was induced, the number who required uterine stimulation in labor, and those cases in which the fetus showed distress and required resuscitation. Also shown are the number of contracted pelves, the number of fetal and maternal deaths and the number showing weight loss during the last one or two weeks before delivery. The main points to emphasize here are: (1) that labor was induced in 8.06 per cent of these primiparas and in 9.19 per cent of the multiparas, which is much above our general average of induction of labor; (2) that uterine stimulation (with pituitrin and, later, with Pitocin when it became available) was required so often because of the large babies and high-riding heads, particularly in the occiput posterior positions, which made for short, weak and infrequent uterine contractions; (3) that fetal distress and resuscitation rate was considerably higher than we have had in non-postmature babies, and (4) that the fetal death rates of 3.66 per cent in primiparas and 2.16 per cent in multiparas (combined average 2.91 per cent) are all above the fetal mortality rate for the State of California, which was 1.8 per cent in 1956 and 1.37 per cen.t in 1960 in white babies, and 1.07 per cent for babies of all races. There were 15 fetal deaths among the 409 primiparous patients for an incidence of 3.66 per cent, and eight fetal deaths among the multiparous patients. The combined incidence was 2.16 per cent (23 deaths). In carefully reviewing these 23 fetal deaths, we found that seven in each group were due to very obvious and definite causes such as a congenital anomaly incompatible with life, short cord complications, luetic infection, premature placental separation and placenta previa. In eight of the babies of primiparas and one of a multipara, no apparent
Postmaturity Babies Table 6.
903
Fetal Deaths from
AGE
DAYS LATE
POSITION
WEIGHT
20
20
L.O:A,
?
25
15
L.O.A.
6-10
31
16
R.S.A.
7-14
30
30
L.O.A.
8
31
24
R.O.A.
7-11
22
19
L.O.A.
7-4.5
34
17
R.O.P.
7-3
29
28
L.O.A.
6-5
23
16
L.O.A.
8-12.5
(lbs.-oz.)
Postmaturity~Causes
TIME OF DEATH
Obscure
COMMENT
Before Stillborn. No life all day. F. H. not labor heard on entry. During Low forceps because of slow, irregular labor fetal heart; meconium; heart beat for 5 min. postpartum. 18 hr. labor During Stillborn. Heart O.K. 1 hour before delabor livery. Easy 10 hour labor and delivery. Before Baby died 10 days before delivery. Lost labor 3 lbs. in last 10 days before delivery. During F. H. not heard for 3 hours before delabor livery. Autopsy: Blood and meconium in bronchi and alveoli. Before Stillborn. No life or F.H. for 24 hours. labor Mature placenta. Scattered areas of lime deposits. Before No life for 24 hours. No F.H. on entry. labor Yellow meconium. Lost 1.5 lbs. in last 2 weeks before delivery. Before Macerated. No movement for 3 days. labor Placenta negative. During Slow F.H. and much meconium started labor 48 minutes before delivery when 4.5 em. dilated. Stillborn. 13 hour labor.
The first 8 are babies of primiparas; the last one is the baby of a para I. F.H. = fetal heart sounds.
reason for the fetal deaths could be seen or found (Table 6). Five of them died before and four during labor. Only two of the babies weighed 8 pounds or more, the majority being under 7 pounds, 14 ounces. The labors were normal and none was over 18 hours, the average being around ten hours. Therefore, big babies and long hard labors were not factors in the deaths of these nine babies. The fact that they were all postmature or postdate was the only thing common to them all. This fact and the lack of any other reason for the fetal deaths make us believe that there is such a thing as postmaturity, with its accompanying placental insufficiency, and that, in a certain small percentage of cases, it is responsible for the death of a fetus. This could be from decreased function of the placenta actually allowing the fetus to die before the onset of labor or lowering its vitality so that it cannot stand the strain and rigors of labor and therefore dies during labor or shortly thereafter. The fact that no characteristic lesion is found in the placenta in a case of postmature pregnancy does not necessarily mean that placenta is functioning perfectly or even sufficiently well to sustain the life of the fetus.
904
PHILIP
H.
ARNOT, DONALD
R.
NELSON
Granted that the duration of a pregnancy is a variable and individual thing and that it takes some women longer to "manufacture" a baby than others, this is no reason to claim that these pregnancies are all due to that individual variability or that we cannot be sure that the pregnancy is really postmature. We cannot shrug the problem off so easily. Our experience with these dead babies convinces us that there are a few real postmature babies among these prolonged pregnancies (2.16 to 3.66 per cent). Furthermore, the babies who die are not necessarily large babies, as all of our nine dead babies, except one, weighed less than 8 pounds. This one weighed 8 pounds, 12 ounces and was born to a multipara. It would seem, therefore, that the size or weight of a baby is not reliable as an indication of postmaturity. Some men say "leave them alone," "let them start up by themselves for there is a higher mortality from induction than from postmaturity." Others advocate the induction of labor, especially when the baby is 20 days or more past due. What should one do? DIAGNOSIS
Before deciding on a course of action, one must establish, if possible, that the pregnancy is actually postdate or postmature. This may be very difficult. The patient must be sure of her last one or two periods and the duration and type of each. She must know whether they were scant, short or according to her usual pattern. Knowing her cycle for the previous year will help. If she menstruates regularly in a 26 to 35 day cycle, we may consider her a postdate possibility. If the cervix is effaced, or effacing, is partially dilated (1 to 3 em.), the presenting part well engaged and the patient two to three weeks past her due date, then we feel that she is definitely due or past due. We then get an x-ray of the abdomen, if the patient is willing (many are afraid of x-ray), hoping to get a picture of the baby's knees to see whether there is ossification present in the proximal tibial epiphyses. If ossification is present, we are inclined to consider this as more evidence that the patient is definitely overdue and that labor should be started. We have been using x-ray during the last three years to aid us in diagnosing postmature babies. Dr. John Bennet, Chief of Radiology at St. Mary's Hospital, San Francisco, has kindly cooperated with us and taken x-rays before the onset of labor and, occasionally, within a few hours after delivery. He has taken x-ray films in 18 postdate patients and found ossification of the proximal tibial epiphyses in 14 of the 18 babies, an incidence of 77.7 per cent. While this is not an absolute
Postmaturity Babies
905
method of diagnosis, we feel that it is of some help. Absence of ossification makes us feel a little more certain that the patient is not overdue and gives us courage to wait a bit longer for labor to start up by itself. An x-ray may also show an abnormal fetus, such as an anencephalic monster or a disproportion between the head and the inlet, which happened in two of our cases. Some patients will have a big baby with a head barely engaged and a cervix without effacement or dilatation and be overdue two to three weeks. We are quite sure that her pregnancy is postmature and it is in these cases that a positive x-ray picture will make us more confident of our diagnosis. WHAT TO DO WHEN THE DIAGNOSIS IS REASONABLY SURE
The patient and her family begin to worry a little when the pregnancy has gone over the expected date of confinement, the amount of worry increasing as each week goes by and they begin to say, "Doctor, can't you take the baby?" We like to induce labor in these patients and always try castor oil first, 1 ounce in a little orange juice. This will start labor in about 75 per cent of the patients in whom the cervix is "ripe." It has occasionally been effective in some cases in which the head was high and the cervix firm, thick and not dilated. Until World War II we gave quinine and castor oil, but quinine became unavailable then, so we had to use castor oil alone. It seemed practically as effective without the quinine, so we have continued to use it alone. Quinine may possibly have been injurious to some babies, so it is just as well that we had to stop using it. The castor oil may be repeated within four to seven days if the first dose is not successful. We do not rupture the membranes unless the head is well or deeply engaged, the cervix thinned out and dilated at least 1 em. We do not give oxytocin (Pitocin) alone to induce labor unless the same situation is present. Castor oil is well worth a trial in a case in which the presenting part is very high, the cervix thick and undilated and where one would not give Pitocin or rupture the membranes. It will sometimes start the labor in such a patient so that she can at least have a trial at it. We have done only two elective cesarean sections for postmaturity and big babies. Both were in primiparas, 38 and 25 days respectively past their due dates, and labor could not be started in them with castor oil (one also had quinine). The babies weighed 9 pounds, 10 ounces and 10 pounds, 1 ounce. For 33 inductions of labor in primiparas, castor oil and quinine were used 25 times, castor oil alone two times, citrate of magnesia and quinine
906
PHILIP
H.
ARNOT, DONALD
R.
NELSON
once, Voorhees bag twice, rupture of membranes followed by nasal Pitocin once, and cesarean section twice. For 34 inductions of labor in multiparas, castor oil and quinine were used 12 times, castor oil alone 12 times, nasal Pitocin four times, Theelin and castor oil twice, rupture of membranes followed by nasal Pitocin twice, rupture of the membranes once and Voorhees bag once. There were no fetal deaths in either of these groups except for one macerated baby which was born to a luetic mother in 1923. The baby had been dead for two weeks before labor was induced with a bag. Those were the days before nasal Pituitrin and before Pitocin was obtainable. We believe that our good results with induction of labor justify its use in an effort to prevent some of these deaths which occur before, during and shortly after delivery and which we believe are due to postmaturity. SUMMARY
1. The question of whether there is such a thing as postmaturity and postmaturity babies is not settled. 2. It is difficult to be sure that a pregnancy is really postmature or postdate. X-ray has not proved as useful as we had hoped as it showed the presence of ossification of the proximal tibial eiphyses in only 77.7 per cent of the cases. It was a small series; we consider it of some value and plan to continue using it as an aid in diagnosis. 3. The weight and length of a baby are not completely reliable as an aid in diagnosis, for many late babies are small. About 48 per cent of our primiparas and 58 per cent of our multiparas had babies weighing between 8 and 12 pounds. 4. There is no characteristic pathological lesion in the placenta in these cases although many show various pathological processes. Similar lesions are often found in term placentas. 5. The high incidence of the occipitoposterior position and the number of large babies makes for more prolonged and difficult labors because their high-riding heads do not produce good uterine irritation. Thus we have weak, short, infrequent pains and long, slow labors, which require uterine stimulation with Pitocin. 6. We believe that some of our babies may have died because of their postmaturity and are now inducing labor in about twice as many patients as we did up to three years ago when we first became seriously interested in this problem. We believe that castor oil is often successful in inducing labor and advise its use. It can be repeated every four to seven days (1 or 2 ounces in a little orange juice) and we have never seen any ill effects from it.
Postmaturity Babies
907
We also believe that oxytocin (Pitocin) alone or with rupture of the membranes is a safe and successful procedure provided the presenting part is well in the pelvis and the cervix well effaced and dilated at least 1 em. We always use Pitocin intranasally (0.5 cc. every half hour) for induction and have found it very successful. The key to success with it is to use a cotton applicator fluffed at the end like a pom-pom and to inject the Pitocin into the cotton with a hypodermic syringe and small needle so that it is not spilled on the floor. One must show and teach the nurse how to prepare it. Finally, we believe that the patient and her family will at least know that we are trying to start labor and this is very reassuring to them for often they really worry when the patient has gone two or three weeks past term and they want something done. This is where castor oil comes in so handily. It is often successful in cases in which we would not use more vigorous methods; it is safe and represents an effort to "take the baby, doctor," which is good public relations. REFERENCES 1. Adams, T. W.: Intrauterine Determination of Fetal Maturity. West. J. Surg., Obst. & Gynec. 65: 197, 1957. 2. Arnot, P. H.: The Duration of Pregnancy. West J. Surg., Obst. & Gynec. 50: 115-125 (March) 1942. 3. Arnot, P. H. and Nelson, D. R.: Experience with Postmaturity. West. J. Surg., Obst. & Gynec. 69: 297-304, 1961. 4. Bancroft-Livingstone, G. and Neill, D. W.: Studies in Prolonged Pregnancy. Part I: Cord Blood Oxygen Levels at Delivery. J. Obst. & Gynaec. Brit. Emp. 64: 498, 1957. 5. Clifford, S. H.: Postmaturity-with Placenta Dysfunction; Clinical Syndrome and Pathological Findings. J. Pediat. 4-~: 1, 1954. 6. Flexner, L. B. and others: Permeability of Human Placenta to Sodium in Normal and Abnormal Pregnancies and Supply of Sodium to Human Fetus, etc. Am. J. Obst. & Gynec. 55: 469, 1948. 7. Kloosterman, G. J.: Prolonged Pregnancy. Gynaecologia 142: 373, 1956. 8. Masters, M. and Clayton, S. G.: Calcification of Human Placenta. J. Obst. & Gynaec. Brit. Emp. 47: 437, 1940. 9. Nesbitt, R. E. L.: Personal communication, 1958. 10. Strand, A.: Prolonged Pregnancy. Acta. obst. et gynec. scandinav. 35: 77, 1956. 11. Walker, J.: Foetal Anoxia. J. Obst. & Gynaec. Brit. Emp. 61: 162, 1954. 12. Walker, J. and Turnbull, E. P. N.: Haemoglobin and Red Cells in Human Foetus and Their Relation to Oxygen Content of Blood in Vessels of Umbilical Cord. Lancet 2: 312, 1953. 13. Wislocki, G. B. and Dempsey, E. W.: Histochemical Age-changes in Normal and Pathological Placental Villi (Hydatidiform Mole, Eclampsia). Endocrinology 8: 90, 1946. 2439 Ocean Avenue San Francisco 27, California (Dr. Arnot)
PHILIP H. ARNOT, M.D., F.A.C.S. Emeritus Clinical Professor of Obstetrics and Gynecology, Um:versity of California School of Medicine; Staff, St. Mary's Hospital
DONALD R. NELSON, M.D., F.A.C.S. Associate Clinical Professor of Obstetrics and Gynecology, University of California School of Medicine; Staff, St. Mary's Hospital
MucH INTEREST has been evident during the last few years in the subject of postmaturity and postmature babies and several articles have appeared in the medical literature on the subject. The term is not a good one as it infers that all babies that remain in utero for 294 or more days, or two weeks more than the·usually figured 280 days, are postmature. The vast majority of such "late" pregnancies are really miscalculations or postdate, overtime, overterm or prolonged pregnancies, to use other terms. We believe, however, that a very few are truly postmature even though it is very difficult or impossible to prove it. The determination of the expected date of confinement is only approximate and the magic number of 280 days as the duration or length of pregnancy has been handed down to us by the people of ancient ages. Centuries ago when the physicians were magicians they sought to explain the onset of labor by happenings or changes of the moon and stars. They came to associate menstruation as something that happened with every full moon, that is, every 28 days. They caJculated that a baby would be carried in utero for ten moon months (280 days) and would be born at the tenfold of the moon, which would also be the tenfold of the menstrual cycle. Thus the folklore of babies being born at the time of a full moon has persisted to the present time. While at Heidelberg, Naegele came forth with his short, rapid method of figuring the expected date of confinement by advising that one count
895
896
PHILIP
H.
ARNOT, DoNALD
R.
NELSON
back three months from the last period and add 7 days. He overlooked the fact that periods do not always occur every 28 days, are often irregular and, furthermore, he did not :my whether to count from the start or end of the menstrual period. Also, there are 12 possible combinations of nine consecutive months and, by subtracting three months and then adding seven days, one gets 280 days seven times, 281 days and 282 days twice, and 283 days once. Most physicians figure from the start of the period in using Naegele's rule and we have always used it in this manner. In 1942 one of us (P.H.A.) went over the records of 3606 private patients for the delivery dates and found that 53.5 per cent were late or went overtime and 42.4 per cent were early or ahead. of time as determined by Naegele's rule, for the same average of 10.2 days. The time of ovulation may also vary considerably in the same individual even though she may menstruate fairly regularly on a 27 to 30 day cycle. So we can see that even if a woman is absolutely sure of her last period and the intervals between the previous ones for a year or more, there is still apt to be considerable error in reckoning the actual duration of the pregnancy because we so seldom know the exact date of conception. Behind this new interest in postmaturity or postdatism is the fact that a certain percentage of postmature babies die during or before labor and in the neonatal period and the question naturally arises as to why they died and how we could have prevented the deaths. Their mothers are patients with perfectly normal prenatal courses and no evidence of toxemia, bleeding, infection or other complications that might be dangerous to the fetus. The first natural question is whether or not these fetal deaths could be due to changes in placental function. There is apparently a placental senescence that sets in or starts about the time of or after term, which might be a factor. Some feel that there is a relative placental insufficiency which could account for this difficulty and that it may occur before term as well as in the patients who go beyond their due date. In a personal communication Nesbitt, in September 1958, said that he does not believe that the problem of postdate pregnancy or postmaturity is chiefly one of progressive placental dysfunction as the pregnancy proceeds beyond term. It seems to be a complex problem characterized by a combination of factors which reduce placental reserve. These patients have larger babies, more abnormal presentations and longer and more difficult labors than do patients delivered at term or under. He feels that there are fetal and uterine as well as placental factors involved in the whole problem. In his experience the preponder-
Postmaturity Babies
897
ance of fetal deaths occurred during labor, usually in association with one or more complicating factors. He finds considerable experimental evidence, such as oxygen gradients across the placental barrier and cord blood studies, to show that postmature pregnancies, uncomplicated by toxemia or difficult labors, maintain a placental function comparable to that noted in mature pregnancies. He has not been able to demonstrate a precise correlation between cord blood counts and gestational age beyond term as Walker reported in 1954 and these data support his clinical impression that the uncomplicated patient who goes beyond term has a good prognosis for the fetus. He feels that the potential hazards to the fetus are principally during labor when more complications occur. Walker and Turnbull in 1953 investigated the hemoglobin and red blood cell content of the fetus at birth and found that the hemoglobin tends to rise from 16.5 gm. at birth (term) to 18.8 gm. at 43 weeks, and Walker in 1954 suggested that this rise in hemoglobin and also in red cell counts is in response to the fall in the oxygen saturation in cord blood that takes place as the pregnancy is prolonged beyond term-a sort of compensatory mechanism. Bancroft-Livingston's and 0. D. Fisher's work in 1958 failed to support the view of Walker that prolongation of pregnancy is associated with hypoxia and, therefore, with a rise in the hemoglobin level, whether the fetus does or does not exhibit clinical evidence of distress before delivery. Clifford believes that there is definitely such a thing as postmaturity and refers to it as "the postmaturity with placental dysfunction." In order for a baby to be classified as postmature, he feels that the pregnancy should be prolonged to 20 days or more beyond the expected date of confinement-that is, 300 or more days of gestation as figured from the beginning of the last period. Clifford divided the babies into three groups or stages as follows. Stage one: There is a loss of vernix from the skin and evidence of malnutrition but the skin is unstained. Stage two: Same findings as in stage one plus a green meconium staining of the amniotic fluid and of the baby's skin, cord and the membranes. Stage three: Evidence of malnutrition may be more severe and the skin, fingernails and cord are stained yellow. PLACENTAL PATHOLOGY
Wislocki and Dempsey demonstrated the aging process of the placenta by means of histochemical studies. They found acid phosphatase in the trophoblastic syncytium only toward the end of gestation whereas
898
PHILIP
H.
ARNO'I', DoNALD
R.
NELSON
alkaline phosphatase was found in the placenta early in pregnancy and increased until term. Strand found age changes starting in the placenta around the seventh month. These changes showed the stroma in the chorionic villi becoming more fibrous and the vascular villi thickened by endarteritis and periarteritis. Syncytium overlying the villi becomes more atrophic and thinner in some areas and fibrin is deposited slowly. Some of the villi degenerate and white infarcts are found as in every mature or term placenta. There are calcareous areas on the maternal surface of the placenta and these are more common on the mature and postmature placentas. Kloosterman found that the average weight of placentas of postmature infants who were born dead or died was 450 gm. as opposed to 535 gm. in those postmaturity infants who were born alive. The placentas of the dead babies showed more infarctions than those of the live babies. Masters and Clayton found that the calcium content of the placentas was very low before the thirty-eighth week of pregnancy and increased in a variable way as term and postmaturity were reached but was generally higher in the postmature pregnancies. They felt that the degree of calcification was an index of the degree of villous degeneration, although villi may degenerate without becoming calcified. In a study correlating radioactive sodium transfer curves with ·the morphologic changes which occur in the placenta during aging, Flexner and his group found a steady increase in placental permeability by the thirty-sixth week, after which there was a marked decrease. This was interpreted as being due to the deposition of fibrin over the surface of the villus. Nesbitt states that he has not been able to demonstrate a placental lesion, either gross or microscopic, which can be considered characteristic and peculiar to postmature pregnancy. He has, however, demonstrated pathologic lesions in the placentas of postmature pregnancies, such as calcification, infarctions of various types, and .areas of disruption and infection. However, he finds these same lesions in placentas of patients who deliver at the regular expected date. He also found that the placentas were larger in postmature pregnancies. In examining nearly 1000 placentas of postdate pregnancies, Nesbitt has not seen objective evidence of excessive aging above that seen in mature pregnancies. He emphasizes, however, that normal structure does not mean the function is also normal. In trying to form some conclusions from what has been written on the subject, we find that most investigators are of the opinion that there are actually few cases of real postmaturity; that they are mostly postdate pregnancies and that, even if there is a slight increase in the fetal mor-
899
Postmaturity Babies
tality in such cases, one should do nothing about it, allow labor to start of its own accord and not induce labor. Many of them believe that the risk of fetal death is greater from induction of labor than from the results of postmaturity and decreased function of the placenta due to its senescence. Others feel that labor should be induced. There seems to be no characteristic, pathognomonic placental lesion of postmaturity but most investigators have found pathological lesions in the placentas of these pregnancies. Our Own Experience
We became interested in this subject in 1957 and 1958 and reviewed our deliveries up to July 1, 1958. We have now reviewed our cases up to December 1, 1961 and present our data and conclusions here. We have had 13,776 private deliveries between July 1, 1922 and December 1, 1961, 779 (5.65 per cent) of which were 14 or more days beyond the expected date of confinement. There were 409 first pregnancies and 370 multiparous pregnancies in this postdate group. Additionally, there were over 100 other pregnancies that were possibly late by 14 or more days but these are not included because of the irregularity of the periods or because the patients were not absolutely certain of their last periods. Table 1 shows the number and percentage of primiparas and multiparas who went overtime as figured by intervals of seven days or weekly Table 1.
Duration of Pregnancy in Weeks and Days
294-300
301-307
308-314
315-321
Days
Days
Days
Days
Days
42-43
43-44
44-45
45-46
46-47
Weeks
Weeks
Weeks
Weeks
Weeks
89 21.5
19 4.64
3
78 21
10 2.7
4 1.08
322-328
Primiparas Number of cases ... 297 Percentage ... ......... 72.6
1 .24
.73
Multiparas Number of cases .... Percentage ........
277 74.8
1 .27
intervals. One sees that about 72 per cent of the primiparas were from 14 to 20 days late (two to three weeks) and that 74.8 per cent of the multiparas were two to three weeks late. Approximately 21 per cent of each group went overtime or past term by 21 to 27 days or three to four weeks. Only a few went over 28 days or four weeks. As to the presentations of the babies, Table 2 shows the number and
900
PHILIP
Table 2.
H.
ARNOT, DONALD
R.
NELSON
Position of Baby
PRIMIPARAS
MULTIPARAS
Number Percentage
Number Percentage
L.O.A ............... 194 R.O.P ............... 91 R.O.A ............... 68 L.O.P ............... 26 L.S.A ............... 11 R.S.A ............... 7 L.S.P ............... 4 R.S.P ............... 1 R.B.A ............... 3 R.M.P .............. 2 L.M.P .............. 0 L.M.A .............. 1 Transverse .......... 1
47.4 22.2 16.6 6.35 2.68 1.7 .97 .24 .73 .48 0 .24 .24
180 62 83 21 4 16 0 1 2 0 1 0 0
48.6 16.7 22.4 5.6 1.08 4.32 0 .27 .54 0 .27 0 0
percentage in each category. The left occiput anterior (L.O.A.) position occurred in approximately 48 per cent of each group; the right occiput positions (R.O.P. and R.O.A.) in about 38 per cent of both, the R.O.P. being slightly more prevalent than R.O.A. in the primiparas while the R.O.A. position was more prevalent than R.O.P. in the multiparas, by the same percentage. Then came L.O.P., 6.35 per cent in the primiparas and 5.67 per cent in the multiparas. There were then a few breech, brow and face presentations in each group and one transverse in a primipara. Most people have the idea that post.mature babies are preponderantly larger than term babies. That. has not. been found in our series. As seen in Table 3, 77 (19.2 per cent) of the babies of primiparous mothers and 42 (11.4 per cent) of the babies of multiparas were between 5 to 7 pounds; 144 (36 per cent) and 110 (29.8 per cent) respectively Table 3. Pounds ................. 5-7 ........... 2300 to Grams .... 3200
Baby Weights
7-8 3201 to 3650
8-9 3651 to 4950
9-10 4096 to 4553
10-11 4554 to 5000
11-12 5001 +
Primiparas Number of cases ....... 77 19.2 Percentage ......
144 36
107 26.7
59 14.2
11 2.77
2
Multiparas Number of cases ....... 42 Percentage ............ 11.4
110 29.8
147 39.9
55 14.9
12 3.26
2
.5
.54
Postmaturity Babies
901
were 7 to 8 pounds; 107 (26.7 per cent) and 147 (39.9 per cent) were 8 to 9 pounds; 59 (14.2 per cent) and 55 (14.9 per cent) were 9 to 10 pounds and 11 (2.77 per cent) and 12 (3.26 per cent) were 10 to 11 pounds. There were only two babies in each group who weighed between 11 to 12 pounds. If one considers only the babies weighing 8 to 12 pounds, we find that 48.1 per cent (about half) of the primiparas and 58.6 per cent (about six out of ten) of the multiparas had what we can call big babies. With 50 to 60 per cent of the babies classified as "large" we could expect that many of these mothers would have long or prolonged labors and more difficult deliveries, with an increased incidence of forceps and cesarean deliveries, at least in the primiparas. Twenty-two per cent of our primiparous mothers had labors of 24 hours or more, which is a larger percentage of long labors than occurred in each of two groups of term primiparas that we reviewed. These were a group of patients with occiput posterior presentations who had 24 hours or more of labor in 17.6 per cent and another group with occiput anterior presentations who had similar prolonged labors in 5.04 per cent. So we must conclude that these longer labors are caused by bigger babies which, in turn, are large because of their postmaturity or postdatism. The methods of delivery are shown in Table 4. The spontaneous Table 4.
Method of Delivery
SPONTANEOUS
CESFORCEPS
BREECH
Primiparas Number of cases ... 177 Percentage ........ 42.2
184 44.9
28 6.84
Multiparas Number of cases ... 312 Percentage ........ 84.3
42 11.3
Av=<' Percentage of ) ... 63.7 Primiparas and
28.1
AREAN
27 6.6
2.95
5 1.35
4.89
3.97
11
VERSION AND EXTRACTION SCANZONI
1
1 .25
0 0
.25 0 0
.24
.24
Multiparas
deliveries in both primiparas and multiparas are less than our general average and the forceps and cesarean deliveries are increased in the primiparas over our general average. We believe that, just as prolonged labors are due to these big babies, the increase in forceps and cesarean deliveries, in the primiparas, is due to the same reason.
902
PHILIP
Table 5.
H.
ARNOT, DONALD
R.
NELSON
Comparative Data PRIMIPARAS
MULTIPARAS
Table 5 shows the number of patients in whom labor was induced, the number who required uterine stimulation in labor, and those cases in which the fetus showed distress and required resuscitation. Also shown are the number of contracted pelves, the number of fetal and maternal deaths and the number showing weight loss during the last one or two weeks before delivery. The main points to emphasize here are: (1) that labor was induced in 8.06 per cent of these primiparas and in 9.19 per cent of the multiparas, which is much above our general average of induction of labor; (2) that uterine stimulation (with pituitrin and, later, with Pitocin when it became available) was required so often because of the large babies and high-riding heads, particularly in the occiput posterior positions, which made for short, weak and infrequent uterine contractions; (3) that fetal distress and resuscitation rate was considerably higher than we have had in non-postmature babies, and (4) that the fetal death rates of 3.66 per cent in primiparas and 2.16 per cent in multiparas (combined average 2.91 per cent) are all above the fetal mortality rate for the State of California, which was 1.8 per cent in 1956 and 1.37 per cen.t in 1960 in white babies, and 1.07 per cent for babies of all races. There were 15 fetal deaths among the 409 primiparous patients for an incidence of 3.66 per cent, and eight fetal deaths among the multiparous patients. The combined incidence was 2.16 per cent (23 deaths). In carefully reviewing these 23 fetal deaths, we found that seven in each group were due to very obvious and definite causes such as a congenital anomaly incompatible with life, short cord complications, luetic infection, premature placental separation and placenta previa. In eight of the babies of primiparas and one of a multipara, no apparent
Postmaturity Babies Table 6.
903
Fetal Deaths from
AGE
DAYS LATE
POSITION
WEIGHT
20
20
L.O:A,
?
25
15
L.O.A.
6-10
31
16
R.S.A.
7-14
30
30
L.O.A.
8
31
24
R.O.A.
7-11
22
19
L.O.A.
7-4.5
34
17
R.O.P.
7-3
29
28
L.O.A.
6-5
23
16
L.O.A.
8-12.5
(lbs.-oz.)
Postmaturity~Causes
TIME OF DEATH
Obscure
COMMENT
Before Stillborn. No life all day. F. H. not labor heard on entry. During Low forceps because of slow, irregular labor fetal heart; meconium; heart beat for 5 min. postpartum. 18 hr. labor During Stillborn. Heart O.K. 1 hour before delabor livery. Easy 10 hour labor and delivery. Before Baby died 10 days before delivery. Lost labor 3 lbs. in last 10 days before delivery. During F. H. not heard for 3 hours before delabor livery. Autopsy: Blood and meconium in bronchi and alveoli. Before Stillborn. No life or F.H. for 24 hours. labor Mature placenta. Scattered areas of lime deposits. Before No life for 24 hours. No F.H. on entry. labor Yellow meconium. Lost 1.5 lbs. in last 2 weeks before delivery. Before Macerated. No movement for 3 days. labor Placenta negative. During Slow F.H. and much meconium started labor 48 minutes before delivery when 4.5 em. dilated. Stillborn. 13 hour labor.
The first 8 are babies of primiparas; the last one is the baby of a para I. F.H. = fetal heart sounds.
reason for the fetal deaths could be seen or found (Table 6). Five of them died before and four during labor. Only two of the babies weighed 8 pounds or more, the majority being under 7 pounds, 14 ounces. The labors were normal and none was over 18 hours, the average being around ten hours. Therefore, big babies and long hard labors were not factors in the deaths of these nine babies. The fact that they were all postmature or postdate was the only thing common to them all. This fact and the lack of any other reason for the fetal deaths make us believe that there is such a thing as postmaturity, with its accompanying placental insufficiency, and that, in a certain small percentage of cases, it is responsible for the death of a fetus. This could be from decreased function of the placenta actually allowing the fetus to die before the onset of labor or lowering its vitality so that it cannot stand the strain and rigors of labor and therefore dies during labor or shortly thereafter. The fact that no characteristic lesion is found in the placenta in a case of postmature pregnancy does not necessarily mean that placenta is functioning perfectly or even sufficiently well to sustain the life of the fetus.
904
PHILIP
H.
ARNOT, DONALD
R.
NELSON
Granted that the duration of a pregnancy is a variable and individual thing and that it takes some women longer to "manufacture" a baby than others, this is no reason to claim that these pregnancies are all due to that individual variability or that we cannot be sure that the pregnancy is really postmature. We cannot shrug the problem off so easily. Our experience with these dead babies convinces us that there are a few real postmature babies among these prolonged pregnancies (2.16 to 3.66 per cent). Furthermore, the babies who die are not necessarily large babies, as all of our nine dead babies, except one, weighed less than 8 pounds. This one weighed 8 pounds, 12 ounces and was born to a multipara. It would seem, therefore, that the size or weight of a baby is not reliable as an indication of postmaturity. Some men say "leave them alone," "let them start up by themselves for there is a higher mortality from induction than from postmaturity." Others advocate the induction of labor, especially when the baby is 20 days or more past due. What should one do? DIAGNOSIS
Before deciding on a course of action, one must establish, if possible, that the pregnancy is actually postdate or postmature. This may be very difficult. The patient must be sure of her last one or two periods and the duration and type of each. She must know whether they were scant, short or according to her usual pattern. Knowing her cycle for the previous year will help. If she menstruates regularly in a 26 to 35 day cycle, we may consider her a postdate possibility. If the cervix is effaced, or effacing, is partially dilated (1 to 3 em.), the presenting part well engaged and the patient two to three weeks past her due date, then we feel that she is definitely due or past due. We then get an x-ray of the abdomen, if the patient is willing (many are afraid of x-ray), hoping to get a picture of the baby's knees to see whether there is ossification present in the proximal tibial epiphyses. If ossification is present, we are inclined to consider this as more evidence that the patient is definitely overdue and that labor should be started. We have been using x-ray during the last three years to aid us in diagnosing postmature babies. Dr. John Bennet, Chief of Radiology at St. Mary's Hospital, San Francisco, has kindly cooperated with us and taken x-rays before the onset of labor and, occasionally, within a few hours after delivery. He has taken x-ray films in 18 postdate patients and found ossification of the proximal tibial epiphyses in 14 of the 18 babies, an incidence of 77.7 per cent. While this is not an absolute
Postmaturity Babies
905
method of diagnosis, we feel that it is of some help. Absence of ossification makes us feel a little more certain that the patient is not overdue and gives us courage to wait a bit longer for labor to start up by itself. An x-ray may also show an abnormal fetus, such as an anencephalic monster or a disproportion between the head and the inlet, which happened in two of our cases. Some patients will have a big baby with a head barely engaged and a cervix without effacement or dilatation and be overdue two to three weeks. We are quite sure that her pregnancy is postmature and it is in these cases that a positive x-ray picture will make us more confident of our diagnosis. WHAT TO DO WHEN THE DIAGNOSIS IS REASONABLY SURE
The patient and her family begin to worry a little when the pregnancy has gone over the expected date of confinement, the amount of worry increasing as each week goes by and they begin to say, "Doctor, can't you take the baby?" We like to induce labor in these patients and always try castor oil first, 1 ounce in a little orange juice. This will start labor in about 75 per cent of the patients in whom the cervix is "ripe." It has occasionally been effective in some cases in which the head was high and the cervix firm, thick and not dilated. Until World War II we gave quinine and castor oil, but quinine became unavailable then, so we had to use castor oil alone. It seemed practically as effective without the quinine, so we have continued to use it alone. Quinine may possibly have been injurious to some babies, so it is just as well that we had to stop using it. The castor oil may be repeated within four to seven days if the first dose is not successful. We do not rupture the membranes unless the head is well or deeply engaged, the cervix thinned out and dilated at least 1 em. We do not give oxytocin (Pitocin) alone to induce labor unless the same situation is present. Castor oil is well worth a trial in a case in which the presenting part is very high, the cervix thick and undilated and where one would not give Pitocin or rupture the membranes. It will sometimes start the labor in such a patient so that she can at least have a trial at it. We have done only two elective cesarean sections for postmaturity and big babies. Both were in primiparas, 38 and 25 days respectively past their due dates, and labor could not be started in them with castor oil (one also had quinine). The babies weighed 9 pounds, 10 ounces and 10 pounds, 1 ounce. For 33 inductions of labor in primiparas, castor oil and quinine were used 25 times, castor oil alone two times, citrate of magnesia and quinine
906
PHILIP
H.
ARNOT, DONALD
R.
NELSON
once, Voorhees bag twice, rupture of membranes followed by nasal Pitocin once, and cesarean section twice. For 34 inductions of labor in multiparas, castor oil and quinine were used 12 times, castor oil alone 12 times, nasal Pitocin four times, Theelin and castor oil twice, rupture of membranes followed by nasal Pitocin twice, rupture of the membranes once and Voorhees bag once. There were no fetal deaths in either of these groups except for one macerated baby which was born to a luetic mother in 1923. The baby had been dead for two weeks before labor was induced with a bag. Those were the days before nasal Pituitrin and before Pitocin was obtainable. We believe that our good results with induction of labor justify its use in an effort to prevent some of these deaths which occur before, during and shortly after delivery and which we believe are due to postmaturity. SUMMARY
1. The question of whether there is such a thing as postmaturity and postmaturity babies is not settled. 2. It is difficult to be sure that a pregnancy is really postmature or postdate. X-ray has not proved as useful as we had hoped as it showed the presence of ossification of the proximal tibial eiphyses in only 77.7 per cent of the cases. It was a small series; we consider it of some value and plan to continue using it as an aid in diagnosis. 3. The weight and length of a baby are not completely reliable as an aid in diagnosis, for many late babies are small. About 48 per cent of our primiparas and 58 per cent of our multiparas had babies weighing between 8 and 12 pounds. 4. There is no characteristic pathological lesion in the placenta in these cases although many show various pathological processes. Similar lesions are often found in term placentas. 5. The high incidence of the occipitoposterior position and the number of large babies makes for more prolonged and difficult labors because their high-riding heads do not produce good uterine irritation. Thus we have weak, short, infrequent pains and long, slow labors, which require uterine stimulation with Pitocin. 6. We believe that some of our babies may have died because of their postmaturity and are now inducing labor in about twice as many patients as we did up to three years ago when we first became seriously interested in this problem. We believe that castor oil is often successful in inducing labor and advise its use. It can be repeated every four to seven days (1 or 2 ounces in a little orange juice) and we have never seen any ill effects from it.
Postmaturity Babies
907
We also believe that oxytocin (Pitocin) alone or with rupture of the membranes is a safe and successful procedure provided the presenting part is well in the pelvis and the cervix well effaced and dilated at least 1 em. We always use Pitocin intranasally (0.5 cc. every half hour) for induction and have found it very successful. The key to success with it is to use a cotton applicator fluffed at the end like a pom-pom and to inject the Pitocin into the cotton with a hypodermic syringe and small needle so that it is not spilled on the floor. One must show and teach the nurse how to prepare it. Finally, we believe that the patient and her family will at least know that we are trying to start labor and this is very reassuring to them for often they really worry when the patient has gone two or three weeks past term and they want something done. This is where castor oil comes in so handily. It is often successful in cases in which we would not use more vigorous methods; it is safe and represents an effort to "take the baby, doctor," which is good public relations. REFERENCES 1. Adams, T. W.: Intrauterine Determination of Fetal Maturity. West. J. Surg., Obst. & Gynec. 65: 197, 1957. 2. Arnot, P. H.: The Duration of Pregnancy. West J. Surg., Obst. & Gynec. 50: 115-125 (March) 1942. 3. Arnot, P. H. and Nelson, D. R.: Experience with Postmaturity. West. J. Surg., Obst. & Gynec. 69: 297-304, 1961. 4. Bancroft-Livingstone, G. and Neill, D. W.: Studies in Prolonged Pregnancy. Part I: Cord Blood Oxygen Levels at Delivery. J. Obst. & Gynaec. Brit. Emp. 64: 498, 1957. 5. Clifford, S. H.: Postmaturity-with Placenta Dysfunction; Clinical Syndrome and Pathological Findings. J. Pediat. 4-~: 1, 1954. 6. Flexner, L. B. and others: Permeability of Human Placenta to Sodium in Normal and Abnormal Pregnancies and Supply of Sodium to Human Fetus, etc. Am. J. Obst. & Gynec. 55: 469, 1948. 7. Kloosterman, G. J.: Prolonged Pregnancy. Gynaecologia 142: 373, 1956. 8. Masters, M. and Clayton, S. G.: Calcification of Human Placenta. J. Obst. & Gynaec. Brit. Emp. 47: 437, 1940. 9. Nesbitt, R. E. L.: Personal communication, 1958. 10. Strand, A.: Prolonged Pregnancy. Acta. obst. et gynec. scandinav. 35: 77, 1956. 11. Walker, J.: Foetal Anoxia. J. Obst. & Gynaec. Brit. Emp. 61: 162, 1954. 12. Walker, J. and Turnbull, E. P. N.: Haemoglobin and Red Cells in Human Foetus and Their Relation to Oxygen Content of Blood in Vessels of Umbilical Cord. Lancet 2: 312, 1953. 13. Wislocki, G. B. and Dempsey, E. W.: Histochemical Age-changes in Normal and Pathological Placental Villi (Hydatidiform Mole, Eclampsia). Endocrinology 8: 90, 1946. 2439 Ocean Avenue San Francisco 27, California (Dr. Arnot)