Term Pregnancy Management in the USA Today: Three Key Concerns
Posting #1 – “Three Things”
There are three things that really bother me about the current state of affairs in the area of term pregnancy management in the USA today. These are:
- The failure to recognize that every term pregnancy is unique, and that broad rules regarding the timing of delivery that are applied to the majority of situations will not produce truly optimal outcomes;
- The failure of most providers to adequately respect the issue of patient autonomy; and
- The current lack of adequate research, and the related lack of interest in generating adequate research, which can answer basic questions about the optimal management of term pregnancy management.
1. THE UNIQUE NATURE OF EVERY PREGNANCY:
Although there are certainly many things that are common to most term pregnancies, there are also multiple factors that are variable (Table 1). The current rules that govern the approach to term pregnancy management emphasize the common elements. “Early term” for all pregnancies now means 37w 0d – 38w 6d. “Late term” for all pregnancies begins at 41w 0d. The 39-week rule is applied exactly at 39w 0d for all pregnancies that do not have an accepted “indication” for delivery prior to that gestational age. Variations in race, socioeconomic status, BMI at conception, EFW, etc., do not change the application of these categorizations, and have little impact on term pregnancy management.
Many providers are now aware of the “debate” concerning the pros vs. cons of delivering ALL pregnancies at 39 weeks that took place at the annual ACOG Meeting last spring (2016). At that “debate” both presenters concluded that birth outcomes would be improved if ALL pregnancies were to be delivered in the 39th week. However, what was missing from the discussion was the consideration that the actual timing of optimal delivery simply must have some kind of variation even within the large pool of “normal” pregnancies. Just from a common sense perspective, a 21 year old nulliparous female with a BMI of 22 at conception, 25 lb. weight gain and absolutely no risk factors is probably biologically different from a 34 year old nulliparous overweight female (BMI 29 at conception) who smokes cigarettes, had excessive weight gain during her pregnancy (+60 lbs.) and suffers from severe chronic depression. It is unlikely that the optimal time of delivery for these two patients is the same – yet neither would qualify for an “indicated” early term delivery, and at my institution the use of labor induction prior to 41 weeks 0 days of gestation would be categorized as “elective.”
It just does not seem unreasonable – with the help of computer technology – to expect that we should not be able to find a way to estimate, with good accuracy, the optimal timing of delivery for each pregnancy. The AMOR-IPAT approach is a first pass at that concept. There is no doubt that much better schemes will be developed. But first must come the understanding that every pregnancy is unique and that the optimal management of each pregnancy will vary from one pregnancy to another.
2. THE ISSUE OF PATIENT AUTONOMY:
I have written previously about the relative lack of patient autonomy in maternity care. However, the issue deserves additional comments. The three medical ethical principles of Autonomy, Beneficence and Justice are taught in all medical schools to all students, along with the fact that the three principles often conflict in actual or real medical situations. In the area of term pregnancy management the principle of Justice is rarely discussed (perhaps that is the subject of a future posting), but the principles of Autonomy and Beneficence regularly conflict. Ideally patients should have a significant say in any medical care that they receive and, if choices are available, those choices should be fairly presented and the patient and provider should develop a plan that is mutually agreeable. Maternity care providers generally feel that it is their obligation to treat the patient in the best possible way (that is the principle of Beneficence). Unfortunately, most maternity care providers – and by that I really mean most providers including mfm’s, ob’s, family doc’s, and midwives – take the position that they “know what is best” for the patient and generally push upon the patient their own set of standards and beliefs.
Ideally there is a balance between Beneficence and Autonomy. The stronger the beliefs and opinions of the patient the greater weight is given to Autonomy. In contrast, the better the scientific basis for a provider-recommended treatment plan the greater weight is given to Beneficence. However, as noted below, the research that is available to support many of the protocols and opinions of providers – both physicians and midwifes – is really quite inadequate. For example, all of the research used to develop the 39-week rule was retrospective. The “evidence” that less favorable outcomes occurred prior to 39 weeks 0 days of gestation came from crude ecological cohort studies or studies of elective cesarean delivery. Such studies should not have been used to generate a strict protocol that severely limited the use of labor induction prior to 39 weeks 0 days of gestation. In a study published earlier this year, the imposition of the 39-week rule has been associated with a significant increase in the rate of term stillbirth in the USA, and there is no published evidence that the 39-week rule has improved any major/important birth outcome.
Standard obstetrical approaches, as reflected by ACOG publications and anti-interventional approaches espoused by midwifery organizations/advocates both seem to imply that providers know what is best their patients with respect to term pregnancy management. However, many of the approaches of either group are adequately supported by high quality research. Consequently, the use of the ethical principle of Beneficence to govern care plans should be used with great care. Rather, patient beliefs and choices should be given more weight than they are currently given. For example, a woman in the 38th week of pregnancy who desires induction of labor prior to 39 weeks 0 days, given a fair presentation of relative risks and benefits of that request, should be provided with induction. In a more extreme example, a woman with a prior history of term stillbirth (death of fetus prior to delivery) should be able to obtain a delivery in the late 37th or 38th week of a subsequent pregnancy. That request is now being regularly refused in most care sites in the USA because of the 39-week rule. And over the past 5 years some women have experienced a second term stillbirth as a direct result of the 39-week rule. As another example, midwives should at this time be forthcoming about recent research that suggests that labor induction might provide certain benefits as well as risks. Conversely, patients who desire to wait beyond 41 weeks for delivery should be allowed to do so provided they are given the options of regular antenatal testing and are given full fair discussion of the risks and benefits of post-term expectant management. In my practice I regularly make recommendations related to the timing of a “preventive” induction. In the past (prior to 2008) this recommendation often involved an induction prior to 39 weeks 0 days of gestation. However, if a patient was not comfortable with my recommended plan and wanted to wait until a later gestational age for a planned delivery (i.e., hoping for the spontaneous onset of labor), then I would always respect the patient’s wishes.
3. THE LACK OF ADEQUATE RESEARCH:
Ideally, medical practices and recommendations are based on high-quality medical research. High-quality research is generally a synonym for randomized clinical trials (RCTs). RCTs randomly assign patients with a given condition to one or more treatments, and then patient outcomes are evaluated so as to determine which treatment provided that best outcomes.
For a variety of reasons, RCTs have not been done with adequate frequency in the area of maternity care (Table 2). Instead, most of the research used to generate the management of term pregnancy has come from retrospective studies (RSs). RSs analyze different methods of care based on clinical activity that has already occurred. Although this does not sound “bad”, the problem with retrospective research is that patients were not “randomized” into the different methods of care. It is well known that lack of randomization can cause the groups that are being treated “differently” to be quite different even before they are treated. The scientific word for those pre-existing differences is “confounding.” As a result, the data that RSs produce, even when fairly analyzed, can lead to misleading or incorrect conclusions.
Because most research studies guiding the current recommendations for the management of term pregnancy were retrospective in nature, the conclusions they produce should be viewed with a certain amount of caution. Strict policies (“standards of care”) should not be based on retrospective studies alone. Rather, RSs should be used to generate an idea or hypothesis about what constitutes an optimal method of care. That idea, or hypothesis, should then be confirmed with an RCT that compares the new method of care with the current standard of care.
Unfortunately, RCTs were not used to develop the 39-week rule. This may have been a deadly error. It is probable that the institution of this rule was partly or entirely responsible for hundreds of term fetal deaths that have occurred in the 38th and 39th weeks of gestation in the USA over the past 5 years.
In contract, a small RCT involving AMOR-IPAT was performed about 10 years ago. This study reported that overall birth outcomes were significantly better following an approach that involved a greater use of preventive labor induction. The timing of preventive labor induction was individualized and was based on each patient’s person risk profile. However, applications for funding for a larger and more definitive RCT involving AMOR-IPAT have been rejected by two major funding agencies (NIH/NICHD x 3 and PCORI x 1).
On a positive note, there is currently a large RCT in progress that is studying the impact of labor induction for first baby patients at 39 weeks of gestation vs. expectant management until 41 weeks of gestation. However, this study does not take into account variations in patient variables in determining the timing of term delivery.
In addition, there may be an RCT underway that compares “laboring down” to immediate pushing in patients having their first baby. If occurring, this is an example of a study that will provide very useful information.
My final comment is that there is a significant dearth of RCTs that evaluate different methods of care for multiparous women (i.e., women who have already had a vaginal birth and who are delivering another baby). The study of multiparous women is especially important because more babies are born to multiparous women than are born from nulliparous women. In my opinion, both PCORI and the NICHD/NIH should be requesting proposals for RCTs that involve innovative methods of care for multiparous term pregnancy.
Postscript 10/23/16 – I have been advised, by a trusted colleague, to try to generate materials on a regular basis to post on the AMOR-IPAT Blog. I have promised to set aside 2 hours a week to develop new postings. I will try to make these postings fully coherent, but at times they may be fragmented and incomplete based on time constraints.
Hopefully more to follow next week……
Possible future topics:
- AMOR-IPAT origination
- Overhearing the comments of others about “elective” inductions
- A different due date for African-American pregnancy in the USA and Europe?
- List of possible research projects
- My collaborators
- The Italian Connection