A clinical trial of induction of labor versus expectant management in postterm pregnancy*,**
Section snippets
METHODS
The trial was designed and implemented by the participants of the Maternal-Fetal Medicine Units Network under the direction and sponsorship of the National Institute of Child Health and Human Development. An investigational new drug (IND) exemption for the use of PGE2 gel was obtained from the Food and Drug Administration. Informed consent was obtained from each participating subject.
RESULTS
Between December 1987 and July 1989 we screened 4566 pregnant women who had reached a gestation of ≥41 weeks. Of these, 4126 were ineligible for the study: 2428 (59%) because of uncertain gestational age, 650 (16%) because of a medical or obstetric complication, 549 (13%) because of a Bishop score of ≥7, 72 (2%) because of decreased amniotic fluid volume, and 100 (2%) because of a nonreactive nonstress test. An additional 323 patients (8%), although eligible, refused to participate in the
COMMENT
This study was stopped because the incidence of the primary outcome variable (perinatal mortality or morbidity) was only 1%. Thus a sample size in excess of 5600 would be required to adequately compare the two schemes described. Because adverse perinatal outcome is so uncommon in postterm pregnancy, the cost of such a trial is not justified. Furthermore, the low prevalence of postterm pregnancy in a well-dated population that is eligible for expectant management (i.e., an unripe cervix, a
ADDENDUM
After submission of our manuscript, the Canadian Multicenter Postterm Pregnancy Trial Group also reported the results of a study of postterm pregnancy. Several differences in the current study and the Canadian study limit a direct comparison of most outcome variables. For example, the Canadian investigators used PGE2 intracervical gel repeatedly, if needed. We administered the agent only once. Further, the Canadian investigators defined a cervical dilatation of 3 cm as an entry criterion
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Cited by (123)
Impact of Maternal-Fetal Medicine Units Network's publications on American College of Obstetricians and Gynecologists guidelines
2022, American Journal of Obstetrics and Gynecology MFMCesarean during labor: Is induction a risk factor for complications?
2019, Journal of Gynecology Obstetrics and Human ReproductionEndocrine Diseases of Pregnancy
2019, Yen & Jaffe's Reproductive Endocrinology: Physiology, Pathophysiology, and Clinical Management: Eighth EditionTiming induction of labour at 41 or 42 weeks? A closer look at time frames of comparison: A review
2018, MidwiferyCitation Excerpt :Pooling these three trials showed no significant difference between IOL and EM (93/629 versus 106/629; RR 0.88; 95%CI 0.68–1.13). RCTs of Chanrachakul et al. (2003), Dyson et al. (1987), Henry (1969), James et al. (2001), Martin et al. (1989), NICHHD (1994), Augensen et al. (1987), Bergsjo et al. (1989), Herabutya (1992), Ocon (1997), Roach (1997) and Witter et al.(1987) were beyond 42 weeks (Table 3). There was no significant difference in the incidence of CS (222/1175 versus 237/1152; RR 0.92; 95%CI: 0.74–1.15).
No. 214-Guidelines for the Management of Pregnancy at 41+0 to 42+0 Weeks
2017, Journal of Obstetrics and Gynaecology CanadaCitation Excerpt :A trial in a Spanish journal was identified through the Cochrane Collaboration and was not reviewed for this document.65 Nine trials began enrolment at 41+0 weeks53,55,56,60–63,66,67 (two of these recruited at 41 weeks but did not randomize until 42 weeks);53,62 one trial at 41+2 weeks68; five trials at 41+3 weeks;49,50,52,54,64 two trials at 42+0 weeks;51,57 and two trials at 42+1 weeks.58,59 Dating was by various methods (menstrual cycle history, positive pregnancy tests, physical examination, and ultrasound) in each of the trials.
No. 214 - Guidelines for the management of pregnancy at 41+0 to 42+0 weeks
2017, Journal of Obstetrics and Gynaecology Canada
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Reprint requests: Donald McNellis, MD, National Institute of Child Health and Human Development, National Institutes of Health, EPN Building, Room 643, Bethesda, MD 20892.
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