Does advanced maternal age confer a survival advantage to infants born at early gestation?

BMC Pregnancy and Childbirth

KS Joseph¹  Emmanuelle Paré²  Sarka Lisonkova² 

[1] School of Population and Public Health, University of British Columbia, Vancouver, Canada;Department of Obstetrics & Gynaecology, University of British Columbia and the Children’s and Women’s Hospital of British Columbia, Vancouver, Canada

关键词: Fetuses-at-risk;    Perinatal mortality;    Birth outcomes;    Advanced maternal age;   

Others  :  1138093
DOI  :  10.1186/1471-2393-13-87

 received in 2012-12-22, accepted in 2013-04-02,  发布年份 2013

【 摘 要 】

Background

Recent studies have shown that older mothers who deliver at preterm gestation have lower neonatal mortality rates compared with younger mothers who deliver at preterm gestation. We examined the effect of maternal age on gestational age-specific perinatal mortality.

Methods

We compared fetal, neonatal and perinatal mortality rates among singleton births in the United States, 2003–2005, to mothers aged ≥35 versus 20–29 years. The analysis was stratified by gestational age and perinatal mortality rates were contrasted by maternal age at earlier (22–33 weeks) and later gestation (≥34 weeks). Gestational age-specific perinatal mortality rates were calculated using the traditional perinatal formulation (deaths among births at any gestation divided by total births at that gestation) and also the fetuses-at-risk model (deaths among births at any gestation divided by fetuses-at-risk of death at that gestation).

Logistic regression was used to estimate adjusted odds ratios (AOR) for perinatal death.

Results

Under the traditional approach, fetal death rates at 22–33 weeks were non-significantly lower among older mothers (AOR 0.97, 95% confidence interval [CI] 0.91-1.03), while rates were significantly higher among older mothers at ≥34 weeks (AOR 1.66, 95% CI 1.56-1.76). Neonatal death rates were significantly lower among older compared with younger mothers at 22–33 weeks (AOR=0.93, 95% CI 0.88-0.98) but higher at ≥34 weeks (AOR 1.26, 95% CI 1.21-1.31). Under the fetuses-at-risk model, both rates were higher among older vs younger mothers at early gestation (AOR for fetal and neonatal mortality 1.35, 95% CI 1.27-1.43 and 1.31, 95% CI 1.24-1.38, respectively) and late gestation (AOR for fetal and neonatal mortality 1.66, 95% CI 1.56-1.76) and 1.21, 95% CI 1.14-1.29, respectively).

Conclusions

Although the traditional prognostic perspective on the risk of perinatal death among older versus younger mothers varies by gestational age at birth, the causal fetuses-at-risk model reveals a consistently elevated risk of perinatal death at all gestational ages among older mothers.

【 授权许可】

   
2013 Lisonkova et al.; licensee BioMed Central Ltd.

【 图 表 】

Figure 1.

Figure 2.

Figure 3.

【 参考文献 】

• [1]Statistics Canada, Canadian Vital Statistics, Birth and Stillbirth Databases 3231 and 3234. CANSIM Tables number 102–4515: Live births and fetal deaths (stillbirths), by type (single or multiple), Canada, provinces and territories, annual (number). http://estat.statcan.gc.ca/cgi-win/cnsmcgi.pgm?LANG=E&CIITables=3871&ResultTemplate=ESTAT\CII_FLST&ROOTDIR=ESTAT/&LangFldr=English/&C2DB= webcite. Table number 102–4515. Accessed in April 2013.
• [2]Statistics Canada: Births 2009. Ottawa: Minister of Industry; 2012. Catalogue no. 84F0210X. http://www.statcan.gc.ca/pub/84f0210x/84f0210x2009000-eng.pdf webcite. Accessed in April 2013
• [3]Martin JA, Hamilton BE, Ventura SJ, Osterman MJK, Kirmeyer S, Mathews TJ, Wilson E: Births: Final data for 2009. National Vital Statistics Reports 2011. Volume 60, Number 1. http://www.cdc.gov/nchs/data/nvsr/nvsr60/nvsr60_01.pdf webcite Accessed: January 2012
• [4]National Center for Health Statistics: Vital Statistics of the United States, 1980, Vol. 1, Natality. DHHS Pub. No. (PHS) 85–1100. Public Health Service. Washington. U.S: Government Printing Office; 1984. http://www.cdc.gov/nchs/data/vsus/nat80_1acc.pdf webcite Accessed: January 2012
• [5]European Commision: Eurostat yearbook 2002; The statistical guide to Europe, Data 1990–2000. Luxembourg: Office for Official Publications of the European Communities; 2002:30. http://epp.eurostat.ec.europa.eu/cache/ITY_OFFPUB/KS-40-01-319/EN/KS-40-01-319-EN.PDF webcite Accessed: April 2013
• [6]Office for Official Publications of the European Communities Luxembourg: Eurostat yearbook 2006–07; Europe in figures. 2007. Catalogue number: KS-CD-06-001-EN-N.68,74. http://epp.eurostat.ec.europa.eu/cache/ITY_OFFPUB/KS-CD-06-001/EN/KS-CD-06-001-EN.PDF webcite Accessed: January 2012
• [7]Linacre S: Australian social trends 2007. In International fertility comparisons. Catalogue No. 4102.0. Australian Bureau of Statistics; 2008. http://www.ausstats.abs.gov.au/Ausstats/subscriber.nsf/0/3938C73A2EBD6847CA25732F001C910D/$File/41020_International%20fertility%20comparison_2007.pdf webcite Accessed: January 2012
• [8]Joseph KS, Allen AC, Dodds L, Turner LA, Scott H, Liston R: The perinatal effects of delayed childbearing. Obstet Gynecol 2005, 105:1410-1418.
• [9]Cnattingius S, Forman MR, Berendes HW, Isotalo L: Delayed childbearing and risk of adverse perinatal outcome. A population-based study. JAMA 1992, 268:886-890.
• [10]Huang L, Sauve R, Birkett N, Fergusson D, van WC: Maternal age and risk of stillbirth: a systematic review. CMAJ 2008, 178:165-172.
• [11]Kanungo J, James A, McMillan D, Lodha A, Faucher D, Lee SK, Shah PS: Advanced maternal age and the outcome of preterm neonates. Obstet Gynecol 2011, 118:872-877.
• [12]Vohr BR, Tyson JE, Wright LL, Perritt RL, Li L, Poole WK: Maternal age, multiple birth, and extremely low birth weight infants. J Pediatr 2009, 154:498-503.
• [13]Department of Health and Human Services, Centre for Disease Control and Prevention, National Centre for Health Statistics, Division of Vital Statistics: Public Use Data File Documentation. 2005. Period Linked Birth/Infant Death Data Set. http://www.cdc.gov/nchs/data_access/Vitalstatsonline.htm webcite Accessed: Dec 2011
• [14]Wier ML, Pearl M, Kharrazi M: Gestational age estimation on United States live birth certificates: a historical overview. Paediatr Perinat Epidemiol 2007, 21(Suppl 2):4-12.
• [15]Mustafa G, David RJ: Comparative accuracy of clinical estimate versus menstrual gestational age in computerized birth certificates. Public Health Rep 2001, 116(1):15-21.
• [16]Joseph KS, Huang L, Liu S, Ananth CV, Allen AC, Sauve R: Reconciling the high rates of preterm and postterm birth in the United States. Obstet Gynecol 2007, 109(4):813-822.
• [17]Ananth CV: Menstrual versus clinical estimate of gestational age dating in the United States: temporal trends and variability in indices of perinatal outcomes. Paediatr Perinat Epidemiol 2007, 21(Suppl 2):22-30.
• [18]Joseph KS, Liu S, Rouleau J, Lisonkova S, Hutcheon JA, Sauve R, Allen AC, Kramer MS: Influence of definition based versus pragmatic birth registration on international comparisons of perinatal and infant mortality: population based retrospective study. BMJ 2012, 344:e746.
• [19]Cunningham FG, Leveno KJ, Bloom SL, Hauth JC, Rouse DJ, Spong CY (Eds): Williams Obstetrics. 23nd ed. Toronto, Canada: McGraw- Hill; 2010:3.
• [20]Yudkin PL, Wood L, Redman CW: Risk of unexplained stillbirth at different gestational ages. Lancet 1987, 1:1192-1194.
• [21]Joseph KS: Incidence-based measures of birth, growth restriction, and death can free perinatal epidemiology from erroneous concepts of risk. J Clin Epidemiol 2004, 57:889-897.
• [22]Yeushalmy J: The relationship of parents’ cigarette smoking to outcome of pregnancy—implications as to the problem of inferring causation from observed associations. Am J Epidemiol 1971, 93:443-456.
• [23]Wilcox AJ: Birth weight and perinatal mortality: the effect of maternal smoking. Am J Epidemiol 1993, 137:1098-1104.
• [24]Joseph KS, Liu S, Demissie K: A parsimonious explanation for intersecting perinatal mortality curves: understanding the effect of plurality and of parity. BMC Pregnancy Childbirth 2003, 3:3. BioMed Central Full Text
• [25]Joseph KS: Exegesis on effect modification – biological or spurious? Paediatr Perinat Epidemiol 2009, 23:417-420.
• [26]Hernandez-Díaz S, Schisterman EF, Hernan MA: The birth-weight “paradox” uncovered? Am J Epidemiol 2006, 164:1115-1120.
• [27]Basso O, Wilcox AJ: Intersecting birthweight-specific mortality curves: solving the riddle. Am J Epidemiol 2009, 169:787-797.
• [28]Platt RW, Joseph KS, Ananth CV, Grondines J, Abrahamowicz M, Kramer MS: A proportional hazards model with time-dependent covariates and time-varying effects for analysis of fetal and infant death. Am J Epidemiol 2004, 160:199-206.
• [29]Joseph KS, Demissie K, Platt RW, Ananth CV, McCarthy BJ, Kramer MS: A parsimonious explanation for intersecting perinatal mortality curves: understanding the effect of race and of maternal smoking. BMC Pregnancy Childbirth 2004, 4:7. BioMed Central Full Text
• [30]Hutcheon JA, Lisonkova S, Joseph KS: Epidemiology of pre-eclampsia and the other hypertensive disorders in pregnancy. Best Pract Res Clin Obstetr Gynaecol 2011, 25:391-403.
• [31]Joseph KS: Theory of obstetrics: the fetuses-at-risk approach as a causal paradigm. JOGC 2004, 26:953-960.
• [32]Joseph KS: The fetuses-at-risk approach: clarification of semantic and conceptual misapprehension. BMC Pregnancy Childbirth 2008, 8:11. BioMed Central Full Text
• [33]Chen XK, Wen SW, Smith G, Yang Q, Walker M: Pregnancy-induced hypertension is associated with lower infant mortality in preterm singletons. BJOG 2006, 113:544-551.
• [34]Piper JM, Langer O, Xenakis EM, McFarland M, Elliott BD, Berkus MD: Perinatal outcome in growth-restricted fetuses: do hypertensive and normotensive pregnancies differ? Obstet Gynecol 1996, 88:194-199.
• [35]Platt RW: The fetuses-at-risk-approach: an evolving paradigm. In Reproductive and perinatal epidemiology. Edited by Buck Lois G, Platt RW. Oxford University Press. Inc;
• [36]Auger N, Delezire P, Harper S, Platt RW: Maternal education and stillbirth: estimating gestational-age-specific and cause-specific associations. Epidemiology 2012, 23(2):247-254.