ResearchObstetricsThe risk of stillbirth and infant death by each additional week of expectant management in twin pregnancies
Section snippets
Materials and Methods
A retrospective cohort study was conducted utilizing 2006-2008 national linked birth certificate and death certificate data. The National Center for Health Statistics links live birth cohort data with infant and fetal death information.1
We utilized stillbirth data at each gestational age week and infant death data following live births at each gestational age week. Data were investigated for twin pregnancies from 20 weeks’ through 42 weeks’ gestational age. Comparisons were made by the
Results
A total of 454,626 twins was included in our analysis of twin gestations with stillbirth or live birth occurring from 32 0/7 through 40 6/7 weeks’ gestational age. Stillbirth was observed in 1585 fetuses (0.35%) and infant death following 2357 live births (0.52%) overall. The risk of stillbirth increased with each additional week of pregnancy (Table 1). However, this increase was statistically significant only between 37 and 38 weeks’ gestation (12.5 per 10,000 vs 22.5 per 10,000) and between
Comment
Our work demonstrates that the risk of immediate delivery is lower than expectant management at 37 weeks’ gestation for unselected twin pregnancies in the absence of fetal anomalies. This corresponds with prior studies that have also recommended this timing of delivery for uncomplicated dichorionic pregnancies.4, 9, 13
When limited to the lower-risk twin pregnancies, excluding gestational diabetes, hypertension, and small-for-gestational-age (SGA)/IUGR pregnancies, 38 weeks became the threshold
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Cited by (24)
Should twin-specific growth charts be used to assess fetal growth in twin pregnancies?
2022, American Journal of Obstetrics and GynecologyCitation Excerpt :The authors speculated that these findings are consistent with the hypothesis that twins are prone to placental insufficiency in the third trimester. However, this study illustrates several important limitations that affect many of the studies on this topic, namely (1) a lack of information on chorionicity, congenital anomalies, and intrapartum complications, which have been shown to be the dominant causes of fetal death in twin pregnancies; (2) a lack of information on the timing of fetal death—instead, this study (and many of the other studies on this topic) used gestational age at birth as a surrogate for gestational age at the time of fetal death, and although this may be reasonable for singleton pregnancies (in which case delivery usually occurs soon after the diagnosis of fetal death), cases of fetal death of 1 twin are usually managed expectantly for the sake of the surviving twin and thus delivery can occur many weeks later; therefore, the use of gestational age at birth as a surrogate for the timing of fetal death overestimates the gestational age-specific risk for fetal death during the late-preterm or early-term period; (3) a lack of information on the cause of fetal death; (4) the risk is reported for the overall cohort of twins irrespective of size at birth; thus, it is not possible to determine whether IUGR was a contributing factor to the excess risk of fetal death in twins; (5) a lack of information or adjustment for important confounding factors such as late maternal age, comorbidities (eg, obesity, diabetes, hypertension) or fertility treatments; (6) variation in the indices used to quantify the risk for fetal death120–122 and the use of a births-based vs fetuses-at-risk model or one of its modifications, such as the prospective risk of stillbirth123; and (7) a lack of information on the management protocols for twin pregnancies including intensity of monitoring and timing of delivery. Indeed, some of the more recent studies, which had more precise data on the timing and etiology of fetal death and could thus overcome some of the limitations described above, have reached contrasting conclusions on the risk for fetal death, especially in the case of dichorionic twins.
Fetal Growth and Stillbirth
2021, Obstetrics and Gynecology Clinics of North AmericaCitation Excerpt :However, the decision to proceed with delivery must take into account the gestational age and the risks to the infant following delivery, particularly if preterm or early term delivery is considered. The point at which the fetal death risk exceeds the predicted infant mortality risk is a reasonable time to consider delivery and has been studied in multiple obstetric contexts.10,55–57 The Society for Maternal-Fetal Medicine and American College of Obstetricians and Gynecologists have developed a guideline to assist physicians with timing and indications for late preterm and early delivery, and this is shown in Fig. 1.29,58
Neonatal mortality in the United States is related to location of birth (hospital versus home) rather than the type of birth attendant
2020, American Journal of Obstetrics and GynecologyCitation Excerpt :Period-linked files use all births in a year as the denominator and all deaths in a year as the numerator, regardless of when the birth occurred (eg, if the birth was in late 2015 and the neonatal death occurred in 2016, that death is counted in the 2016 numerator). Studies using linked US birth and death records are considered reliable and have been used in numerous studies.11–14 The 2010–2017 period-linked birth and infant deaths dataset10 was analyzed to examine neonatal mortality (defined as the death of a live-born neonate days 0–27 of life in term (≥37 weeks), normal size (birthweight of ≥2500 g), singleton births by birth setting (planned home and hospital) and attendant: hospital-certified nurse-midwife, planned home birth–certified nurse-midwife, planned home birth by direct-entry midwife, and planned home birth attendant not identified.
Trial of labor after cesarean delivery in twin gestations: systematic review and meta-analysis
2019, American Journal of Obstetrics and GynecologyA mouse model of antepartum stillbirth
2017, American Journal of Obstetrics and GynecologyThe risk of stillbirth and infant death by each additional week of expectant management in twin pregnancies
2015, American Journal of Obstetrics and Gynecology
J.M.S. is supported by the Eunice Kennedy Shriver National Institute of Child Health and Human Development (grant K99 HD079658-01).
The authors report no conflict of interest.
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Cite this article as: Page JM, Pilliod RA, Snowden JM, et al. The risk of stillbirth and infant death by each additional week of expectant management in twin pregnancies. Am J Obstet Gynecol 2015;212:630.e1-7.