Fetal and Neonatal Mortality Among Twin Gestations in a Canadian Population: The Effect of Intrapair Birthweight Discordance

Shi Wu Wen; Karen Fung Kee Fung; Ling Huang; Kitaw Demissie; K. S. Joseph; Alexander C. Allen; Michael S. Kramer; for the Fetal and Infant Health Study Group of the Canadian Perinatal Surveillance System

doi:10.1055/s-2005-870899

American Journal of Perinatology, Inhaltsverzeichnis

Am J Perinatol 2005; 22(5): 279-286
DOI: 10.1055/s-2005-870899

Fetal and Neonatal Mortality Among Twin Gestations in a Canadian Population: The Effect of Intrapair Birthweight Discordance

Shi Wu Wen¹ ^, ² ^, ³ , Karen Fung Kee Fung² , Ling Huang¹ , Kitaw Demissie⁴ , K. S. Joseph⁵ , Alexander C. Allen⁵ , Michael S. Kramer⁶ , for the Fetal and Infant Health Study Group[*] of the Canadian Perinatal Surveillance System

¹Health Surveillance and Epidemiology Division, Centre for Healthy Human Development, Health Canada, Ottawa, Ontario, Canada
²Department of Obstetrics and Gynecology, Faculty of Medicine, and the University of Ottawa, Ottawa, Ontario, Canada
³Clinical Epidemiology Program, University of Ottawa, Ottawa, Ontario, Canada
⁴Division of Epidemiology, University of Medicine and Dentistry of New Jersey, School of Public Health, Piscataway, New Jersey
⁵Perinatal Epidemiology Research Unit, Departments of Obstetrics and Gynecology and of Pediatrics, Dalhousie University, Halifax, Nova Scotia, Canada
⁶Departments of Pediatrics and of Epidemiology and Biostatistics, McGill University, Montreal, Quebec, Canada

Abstract

ABSTRACT

The purpose of this study was to examine the association between intrapair birthweight discordance and fetal and neonatal mortality. This was a historical cohort study, using the Statistics Canada linked birth-infant death file. Twin births in Canada (excluding Ontario) for the period 1986-1997 were studied.

Outcome measures were fetal and neonatal mortality. Among 59,034 twin births, 53% had 0 to 9% birthweight difference; 30% had 10 to 19% discordance; 11% had 20 to 29% discordance; and 6% had ≥ 30% discordance. Maternal age, parity, sex discordance, and gestational age were important factors affecting birth weight discordance. Fetal death rates were 0.95, 1.26, 3.14, and 11.10%, respectively, in infants with a birthweight discordance of 0 to 9, 10 to 19, 20 to 29, and ≥ 30%. Corresponding figures for neonatal death rates were 1.90, 2.32, 3.05, and 8.86%, respectively. Adjustment for important confounding variables including the actual birthweight and gestational age substantially reduced the birthweight discordance-related risk of fetal and neonatal mortality, but the results remained statistically significant and clinically important. The birthweight discordance-related risk of fetal and neonatal mortality was higher in smaller twins than in larger twins and higher in infants with gestational age ≥ 37 weeks than those < 37 weeks. Birthweight discordance is an important risk factor for fetal and neonatal mortality, and the birthweight discordance-related risk of fetal and neonatal mortality is higher in smaller twins than in larger twins and higher in term twins than in preterm twins.

KEYWORDS

Twins - birthweight discordance - fetal death - infant death - Canada

Volltext

Referenzen

REFERENCES

7 Contributing members: Margaret Cyr (Statistics Canada), Martha Fair (Statistics Canada), Arne Ohlsson (University of Toronto), I.D. Rusen (Health Canada).

1 Patterson R M, Wood R C. What is twin birthweight discordance?. Am J Perinatol. 1990; 7 217-219
2 Erkkola R, Ala-Mello S, Piiroinen O, Kero P, Sillanp M. Growth discordancy in twin pregnancies: a risk factor not detected by measurement of biparietal diameter. Obstet Gynecol. 1985; 66 203-206
3 Hollier L M, McIntire D D, Leveno K J. Outcome of twin pregnancies according to intrapair birthweight differences. Obstet Gynecol. 1999; 94 1006-1010
4 Rydhstroem H. The relationship of birthweight and birthweight discordance to cerebral palsy or mental retardation later in life for twins weighing less than 2500 grams. Am J Obstet Gynecol. 1995; 173 680-686
5 Fraser D, Picard R, Picard E, Leiberman J R. Birthweight discordance, intrauterine growth retardation and perinatal outcomes in twins. J Reprod Med. 1994; 39 504-508
6 Hsieh T, Chang T, Chiu T, Hsu J, Chao A. Growth discordancy, birthweight and neonatal adverse events in third trimester twin gestations. Gynecol Obstet Invest. 1994; 38 36-40
7 Fair M E, Cyr M. The Canadian birth data base: a new research tool to study reproductive outcomes. Health Reports. 1993; 5 281-290
8 Howe G R, Lindsay J. A generalized iterative record linkage computer system for use in medical follow-up studies. Comput Biomed Res. 1981; 14 327-340
9 Smith M E, Silins J. Generalized iterative record linkage system. In: Proceedings of the American Statistical Association, Social Statistics Section Detroit, Michigan; August 10-13, 1981: 128-137
10 Joseph K S, Kramer M S. Recent trends in infant mortality rates and proportions of low-birth-weight live births in Canada. Can Med Assoc J. 1997; 157 535-541
11 Rydhstrom H. Discordant birthweight and late fetal death in like-sexed and unlike-sexed twin pairs: a population-based study. Br J Obstet Gynecol. 1994; 101 765-769
12 Yalcin H R, Zorlu G, Lembet A, Ozden S, Gokmen O. The significance of birthweight difference in discordant twins: a level to standardize?. Acta Obstet Gynecol Scand. 1998; 77 28-31
13 Cheung V YT, Bocking A D, Dasilva O P. Obstetrics: preterm discordant twins: what birthweight difference is significant?. Am J Obstet Gynecol. 1995; 172 955-959
14 Demissie K, Ananth C V, Martin J, MacDorman M F, Rhoads G G. Fetal and neonatal mortality among twin gestations in the United States: the role of intrapair birthweight discordance. Obstet Gynecol. 2002; 100 474-480
15 Talbot G T, Goldstein R D, Nesbirt T, Johnson J L, Kay H H. Is size discordancy an indication for delivery of preterm twins?. Am J Obstet Gynecol. 1997; 177 1050-1054
16 Blickstein I, Shoham-Schwartz Z, Lancet M, Borenstein R. Characterization of the growth-discordant twin. Obstet Gynecol. 1987; 70 11-15
17 O'Brien W F, Knuppel R A, Scerbo J C, Rattan P K. Birthweight in twins: an analysis of discordancy and growth retardation. Obstet Gynecol. 1986; 67 483-486
18 Crane J P, Tomich P G, Kopta M. Ultrasonic growth patterns in normal and discordant twins. Obstet Gynecol. 1980; 55 678-683
19 Storlazzi E, Vintzileos A M, Campbell W A, Nochimson D J, Weinbaum P J. Ultrasonic diagnosis of discordant fetal growth in twin gestations. Obstet Gynecol. 1987; 69 363-367
20 Blickstein I, Friedman A, Caspi B, Lancet M. Ultrasonic prediction of growth discordancy by intertwin difference in abdominal circumference. Int J Gynecol Obstet. 1989; 29 121-124
21 Rodis J F, Vintzileos A M, Campbell W A, Nocimson D J. INtrauterine fetal growth in discordant twin gestations. J Ultrasound Med. 1990; 9 443-448
22 Lanni R, Fusco D, Marinacci C, Grimaldi V, Corchia C, Mastroiacovo P. Birthweight discordancy in twins: new definition and standard. Eur J Obstet Gynecol Reprod Biol. 1998; 76 37-40
23 Cooperstock M S, Tummaru R, Bakewell J, Schramm W. Twin birthweight discordance and risk of preterm birth. Am J Obstet Gynecol. 2000; 183 63-67
24 Kramer M S, Demissie K, Yang H, Platt R W, Sauve R, Liston R. The contribution of mild and moderate preterm birth to infant mortality. JAMA. 2000; 284 843-849
25 Eberle A M, Levesque D, Vintzileos A M, Egan J F, Tsapanos V U, Salafia C M. Placental pathology in discordant twins. Am J Obstet Gynecol. 1993; 169 931-935
26 Wenstrom K D, Tessen J A, Zlatnik F J, Sipes S L. Frequency, distribution, and theoretical mechanisms of hematologic and weight discordance in monochorionic twins. Obstet Gynecol. 1992; 80 257-261

Dr.
Shi Wu Wen

The Ottawa Hospital, General Campus, 501 Smyth Road

Box 241, Ottawa, Ontario, Canada