Obstetrics & Gynecology:
Advanced Maternal Age and Adverse Perinatal Outcome
Jacobsson, Bo MD, PhD; Ladfors, Lars MD, PhD; Milsom, Ian MD, PhD
From the Perinatal Centre, Department of Obstetrics and Gynecology, Sahlgrenska University Hospital/Östra, Göteborg, Sweden.
The study was supported by the Göteborg Medical Society and Sahlgrenska Academy at Göteborg University.
Address reprint requests to: Bo Jacobsson, MD, PhD, Department of Obstetrics and Gynecology, Sahlgrenska University Hospital/Östra, S-416 85 Göteborg, Sweden; e-mail: firstname.lastname@example.org.
Received March 27, 2004. Received in revised form June 18, 2004. Accepted July 1, 2004.
OBJECTIVE: The aim of this study was to investigate the influence of maternal age on perinatal and obstetric outcome in women aged 40–44 years and those 45 years or older and to estimate whether adverse outcome was related to intercurrent illness and pregnancy complications.
METHODS: National prospective, population-based, cohort study in women aged 40–44 years and those 45 years or older and in a control group of women aged 20–29 years who delivered during the period 1987–2001. Adjusted odds ratios (OR) were calculated after adjustments for significant malformations, maternal pre-existing diseases, and smoking. Main outcome measures were perinatal mortality, intrauterine fetal death, neonatal death, preterm birth, and preeclampsia.
RESULTS: During the 15-year period, there were 1,566,313 deliveries (876,361 women were 20–29 years of age, 31,662 were 40–44 years, and 1,205 were ≥ 45 years). Perinatal mortality was 1.4%, 1.0%, and 0.5% in women 45 years or older, 40–44, and 20–29 years, respectively. Adjusted OR for perinatal mortality was 2.4 (95% confidence interval [CI] 1.5–4.0) in women aged 45 years or older, compared with 1.7 (95% CI 1.5–1.9) in women 40–44 years. Adjusted OR for intrauterine fetal death was 3.8 (95% CI 2.2–6.4) in women aged 45 years or older, compared with 2.1 (95% CI 1.8–2.4) in women 40–44 years. Preterm birth, gestational diabetes, and preeclampsia were more common among women 40–44 years of age and those 45 years or older. Perinatal mortality was increased in women with intercurrent illness or pregnancy complications compared with women without these conditions, but there was no evidence that these factors became more important with increasing age.
CONCLUSION: Perinatal mortality, intrauterine fetal death, and neonatal death increased with age. There was also an increase in intercurrent illnesses and pregnancy complications with increasing age, but this did not entirely explain the observed increase in perinatal mortality with age.
LEVEL OF EVIDENCE: II-3
During the last 3 decades, there has been an increasing trend among women in the industrialized world to delay childbearing. In Sweden, the mean maternal age at the birth of the first child increased between 1974 and 2001 from 24.4 to 28.5 years.1 The corresponding mean maternal age increased from 21.4 to 24.9 years in the United States and from 25.6 to 28.0 years in Japan between 1970 and 2000.2
The proportion of women delivering in their 40s has also increased, especially during the last decade. In Sweden, the numbers of women giving birth between 40 and 44 years of age and at age 45 or older increased from 5.0 to 10.3 and from 0.2 to 0.5 live births per 1,000 women, respectively, from the early 1980s to 2001.3 In England and Wales, the number of women giving birth between 40 and 44 years and at 45 years or older increased from 5.1 to 8.4 and 0.3 to 0.5 live births per 1,000 women, respectively, between 1991 and 2001.4 In the United States, the number of women giving birth between 40 and 44 years and at 45 years or older increased from 3.8 to 7.4 and 0.2 to 0.4 live births per 1,000 women, respectively, between 1981 and 1999.5
It is a well-established fact that fecundity decreases and the risk for miscarriage increases with age.6 However, the enormous advances in reproductive medicine have compensated, to some extent, for this natural decrease in fecundity, and nowadays even postmenopausal women have become pregnant through oocyte donation.7 The influence of advanced maternal age and delayed childbearing on perinatal outcome have previously been studied, but most studies have evaluated outcome in women aged 35 years or older.6 It has been shown that pregnant women aged 35 years or older experience an increased risk of intrauterine fetal death, pregnancy-induced hypertension, gestational diabetes, and delivery by cesarean.6
Most studies that have dealt with advanced maternal age are hospital-based; there are very few population-based studies.8,9 Two hospital-based studies have investigated women aged 45 years or older.10,11 The aim of this national population-based study was to 1) investigate the influence of maternal age on perinatal and obstetric outcome in women aged 40–44 years and those 45 years or older and 2) explore whether the increased risk of perinatal mortality could be explained by the increased occurrence of intercurrent illnesses and pregnancy complications among older women.
MATERIALS AND METHODS
The Swedish Medical Birth Register, managed by the National Board of Health and Welfare, contains data on more than 99% of all births in Sweden.12 Information is collected prospectively by the staff responsible for the care of the patient and includes demographic data, reproductive history, and complications during pregnancy, delivery, and the neonatal period. Copies of the standardized individual antenatal, obstetric, and pediatric records are forwarded to the Birth Registry, where the information is automatically entered into a database and stored. All births and deaths are validated every year through individual record linkage to the Swedish Register of the total population, using the mothers’ and infants’ unique national registration numbers, which are assigned to each Swedish resident at birth. The register has been validated and quality is controlled on a yearly basis. Maternal complications during pregnancy are considered to be of acceptable quality.12
The women included in the study are part of the homogenous, low-risk population typical for Sweden. Severe poverty does not really exist in Sweden, and access to adequate prenatal and obstetrical care is good. More than 80% of women have an intermediate or high level of education, and the prevalence of drug/alcohol abuse is low in comparison with many other countries.
Pre-existing maternal diseases and medical complications in pregnancy and delivery are recorded in the birth registry according to the Swedish version of the International Classification of Diseases, 9th Revision (ICD-9) 1987–1996. From 1997, the Swedish version of the International Classification of Diseases, 10th Revision (ICD-10) was used. Smoking and marriage/cohabitation status were also recorded at the first antenatal visit and categorized as either nonsmoking (ie, non-daily smoking) or smoking and either marriage/cohabitation or not. Intercurrent illness was defined as the presence of a prepregnancy history of existing hypertensive disease, diabetes, bronchial asthma, disseminated lupus erythematosus, or inflammatory bowel disease, and these were recorded at the first antenatal visit. Complication during pregnancy was defined as a history of gestational diabetes, pregnancy-induced hypertension, or preeclampsia during the pregnancy.
Pregnancy outcomes, such as stillbirth, birth weight, gestational age at delivery, and infant gender, are recorded in the delivery or pediatric records. Validation of the Birth Register has concluded that data on birth weight, gestational age, and stillbirth are correctly recorded.12 The Birth Register includes information on all live births, as well as stillbirths, occurring at 28 completed gestational weeks or later. Information necessary to determine maternal mortality was obtained from the national Causes of Death Register. The study was approved by the Ethics Committee, Faculty of Medicine, University of Göteborg, and by the governing board of the Swedish Medical Birth Register.
From 1987 to 2001, there were 1,566,313 recorded births. All deliveries in women aged 40–44 (n = 31,662) years and 45 years or older (n = 1,205) and in a control group of all women aged 20–29 years (n = 876,361) were included in this study.
Gestational age was calculated by using information from date of birth and estimated date of delivery as determined in early pregnancy. This is usually based on a second-trimester ultrasound scan performed at no later than 18 completed weeks of gestation, which was offered to all pregnant women in Sweden during the study period. More than 95% of pregnant women avail themselves of this opportunity.13
Small for gestational age (SGA) was defined as a birth weight below 2 standard deviations from the mean weight corrected for gestational age and gender.14 Large for gestational age (LGA) was defined as a birth weight more than 2 standard deviations from the mean weight corrected for gestational age and gender.14
Perinatal mortality was defined as stillbirth or death during days 0–6. Neonatal death was defined as born alive and death during days 0–28. Perinatal death was defined as stillbirth or neonatal death. Stillbirth was defined as a dead fetus (both antepartum and intrapartum) born at 28 completed gestational weeks or later (information on weeks 22–27 is not available in the Registry according to Swedish legislation). All mortality and death data were expressed as deaths per 1,000 deliveries.
Dichotomous data were tested for significance with the Fisher exact test, and adjustments (multiplication by 3) of the P values due to multiple comparisons were performed by the Bonferroni method (Table 1). Logistic regression was used to analyze selected antepartum complications (diabetes mellitus, hypertensive disease, mild and severe preeclampsia, and placenta previa) (Table 2), as well as intrapartal variables (mode of delivery, induction of labor, and sphincter tears of the third and fourth degree) (Table 3) and perinatal mortality according to the presence or absence of intercurrent illness and/or pregnancy complications (Table 4), in comparing the different age groups. Using multiple logistic regression analysis, perinatal outcomes were adjusted for nulliparity, married/cohabitating, significant malformations, smoking, maternal disease, and multiple pregnancy (Tables 5 and 6).
Odds ratios (OR) were calculated, with women 20–29 years of age as the reference group, with 95% confidence intervals (CI). Statistical software (SAS 8.12; SAS Institute Inc, Cary, NC) was used for the analysis.
The proportion of women giving birth between ages 40 and 44 years and at 45 years or older has increased during the study period (Fig. 1, A and B). During the study period (1987–2001), the number of women giving birth between ages 40 and 44 years increased from 6 to 10 live births per 1,000 women. The corresponding increase for women aged 45 years or older was from 0.2 to 0.3 live births per 1,000 women.
Demographic characteristics and medical history, grouped according to maternal age, are shown in Table 1. Fewer women in the age groups 40–44 years and 45 years or older smoked and lived with the child's father than women in the age group 20–29 years. The older women had more pre-existing diagnoses of hypertension, disseminated lupus erythematosus, and ulcerative colitis, but not diabetes mellitus or renal disease.
The risk of developing gestational diabetes, pregnancy-induced hypertension, severe preeclampsia, or placenta previa increased with increasing maternal age, but there was a decreased risk of mild preeclampsia (Tables 2 and 6). The number of uncomplicated deliveries was lower in older women (Table 3). Both induction of labor and cesarean delivery were increased, but not operative vaginal delivery (not corrected for multiparty). In women aged 45 years or older, 1 of every 3 women was delivered by cesarean. The risk of experiencing an anal sphincter tear increased with increasing age.
Adjusted ORs were calculated regarding perinatal outcome. Perinatal mortality, perinatal death (including death within the first 28 days of life), and intrauterine fetal death all increased with increasing maternal age. Neonatal death (defined as death within 28 days) was also increased in women aged 40–44 years (Table 5). The absolute risk of an intrauterine fetal death or the death of the live-born child within the first 27 days of life was 1.1% in women aged 40 years or older and 1.7% in women 45 years or older. Adjusted ORs were also calculated for other important perinatal outcome measures: preterm birth, SGA, LGA, and preeclampsia (mild and severe), and these outcomes were all found to be associated with increased maternal age (Table 6).
Perinatal mortality was increased in women with intercurrent illness or pregnancy complications compared with women not experiencing these conditions, in both women aged 20–29 years and 40–44 years (Table 4). However, there was no evidence that intercurrent illness or pregnancy complications become more important risk factors for perinatal death with increasing age (20–29 years: OR 1.28, 95% CI 1.16–1.41; 40–44 years: OR 1.17, 95% CI 0.82–1.69). Similar results were obtained for intrauterine fetal death and perinatal death in women grouped in the corresponding manner.
During the course of this study, which stretched over 15 years, there were 21 maternal deaths in the age groups studied. Maternal mortality, grouped according to age group, was calculated (age group 20–29 years: 12/876,361, which is equivalent to 1.4/100,000 deliveries; age group 40–44 years: 7/31,662, which is equivalent to 22.1/100,000 deliveries; age group ≥ 45 years: 2/1,205, which is equivalent to 166.0/100,000 deliveries). Maternal mortality was compared between groups: age group 40–44 years versus age group 20–29 years OR 16.2 (95% CI 6.38–41.2); age group 45 years or older versus age group 20–29 years OR 121 (95% CI 27–542).
This study has demonstrated an increase in perinatal mortality, perinatal death, intrauterine fetal death, and neonatal death in relation to maternal age in childbearing women from the last part of their fertile period, ie, 40–44 years of age and 45 years or older. In addition, there was also an increase in the preterm birth rate and the prevalence of SGA, LGA, and preeclampsia with advancing maternal age, and again, the highest prevalences were seen in women 45 years of age or older. Our data suggest that the increased occurrence of perinatal mortality, perinatal death, and intrauterine fetal death in older women could not be explained by the increased frequency of intercurrent illness or pregnancy complications observed in these women. One can, however, have possible reservations regarding the validity of this conclusion, if pregnancy complications had been underreported, but on the other hand, we see no reason why underreporting should differ between the various age groups.
Being pregnant and giving birth at the age of forty or more years was relatively common until the middle of the 20th century.14 Women often had their first child early and their last child late during the reproductive period.14 The major difference during the last 3 decades is that women are more often using the latter part of their reproductive period to have all their children,1 and this trend of postponing childbearing has not yet shown any tendency to decrease.1 Several studies have investigated perinatal outcome in women aged 40 years or older,9,15–21 and 2 of the studies have presented population-based data.8,9 The study by Cnattingius et al8 was population-based and demonstrated a higher prevalence of late fetal death but was unable to demonstrate a higher prevalence of early neonatal death in women who delivered at the age of 40–52 years, compared with 35- to 39-year-old women. In their study the number of women aged 40 years or older was limited (n = 1,069), and it was not possible to compare women aged 40–44 years with those 45 years or older. Thus, it was not possible to demonstrate an increase in perinatal mortality, perinatal death, intrauterine fetal death, and neonatal death with increasing age in women aged 40 years or older as was demonstrated in the present study. In the study by Gilbert et al,9 increased infant and neonatal death could only be demonstrated in multiparous women 40 years of age or older compared with the younger control group, and again no distinction was made between women aged 40–44 years and those who were 45 years of age or older.
There are only 2 earlier studies published regarding perinatal outcome in childbearing women aged 45 years or older; both studies are hospital-based and the size of the studies was insufficient to study perinatal mortality.10,11 Dildy et al10 presented 79 cases from their hospital and also performed a review of the literature between 1948 and 1996 of studies presenting data from women aged 45 years or older. Also, Dulitzki et al11 have presented a hospital-based, case-control study with 109 women. The size and comprehensiveness of our present study provided us the opportunity to study the important perinatal outcome variables.
The present study was based on a large national population-based cohort where 31,662 women aged 40–44 years and 1,205 women aged 45 years or older were included in the analyses. It was also possible, because of the design of the Swedish Medical Birth Register, to adjust for important pre-existing maternal conditions, nulliparity, significant malformations, multiple pregnancies, smoking, and cohabitation. The ability to link the Swedish Medical Birth Register to other relevant national population registers enhanced the quality control of the data available for the important mortality figures. Being able to adjust for parity and important potential confounding factors enhanced our ability to investigate the specific influence of age on perinatal outcome. No attempt was made to adjust for the use of in vitro fertilization techniques or oocyte donation because the validity of this information contained in the antenatal records alone has been considered to be of poorer quality.22 During the study period, oocyte donation was not legally available in Sweden, but it is possible that there may be a few cases in our material because some women may have undergone oocyte donation treatment abroad and were subsequently delivered in Sweden. Another possible limitation of this study is that it covers a 15-year time period, and treatment policies have changed during the course of the study.
We conclude that there is an increase in perinatal and neonatal death with increasing age, as well as an increase in pregnancy complications, eg, preterm delivery, SGA, LGA, gestational diabetes, pregnancy-induced hypertension, severe preeclampsia, and anal sphincter tears. However, although maternal and fetal outcome is compromised, pregnancies in women aged 40–44 years and 45 years or older still may be considered to be relatively safe because the occurrence of perinatal death is rare. An important observation in this study is that the increased risk of bad perinatal outcome is not due to the increased occurrence of maternal pre-existing disease or pregnancy complications in the older women. Our findings are of importance for gynecologists and obstetricians, as well as the general public, when providing information to the increasing numbers of presumptive parents where the woman is aged 40 years or older. However, from the clinician's perspective, there is no simple measure that could be applied to prevent the poor outcome.
1. Annual vital statistics, Part 4. Örebro, Sweden: Statistics Sweden; 2002.
2. Mathews TJ, Hamilton BE. Mean age of mothers, 1970–2000. Hyattsville (MD): National Center for Health Statistics; 2002.
3. Statistical yearbook of Sweden 2003. Örebro, Sweden: Statistics Sweden; 2003.
4. Births statistics. London (UK): Office for National Statistics; 2002.
5. Vital statistics of the United States, 1999. Hyattsville (MD): National Center for Health Statistics; 2002.
6. Hansen JP. Older maternal age and pregnancy outcome: a review of the literature. Obstet Gynecol Surv 1986;41:726–42.
7. Paulson RJ, Boostanfar R, Saadat P, Mor E, Tourgeman DE, Slater CC, et al. Pregnancy in the sixth decade of life: obstetric outcomes in women of advanced reproductive age. JAMA 2002;288:2320–3.
8. Cnattingius S, Forman MR, Berendes HW, Isotalo L. Delayed childbearing and risk of adverse perinatal outcome: a population-based study. JAMA 1992;268:886–90.
9. Gilbert WM, Nesbitt TS, Danielsen B. Childbearing beyond age 40: pregnancy outcome in 24,032 cases. Obstet Gynecol 1999;93:9–14.
10. Dildy GA, Jackson GM, Fowers GK, Oshiro BT, Varner MW, Clark SL. Very advanced maternal age: pregnancy after age 45. Am J Obstet Gynecol 1996;175:668–74.
11. Dulitzki M, Soriano D, Schiff E, Chetrit A, Mashiach S, Seidman DS. Effect of very advanced maternal age on pregnancy outcome and rate of cesarean delivery. Obstet Gynecol 1998;92:935–9.
12. Cnattingius S, Ericson A, Gunnarskog J, Kallen B. A quality study of a medical birth registry. Scand J Soc Med 1990;18:143–8.
13. Report No. 139. Stockholm, Sweden: The Swedish Council on Technological Assessment in Health Care; 1998.
14. Annual vital statistics, Part 3. Stockholm, Sweden: Statistics Sweden; 1968.
15. Bianco A, Stone J, Lynch L, Lapinski R, Berkowitz G, Berkowitz RL. Pregnancy outcome at age 40 and older. Obstet Gynecol 1996;87:917–22.
16. Spellacy WN, Miller SJ, Winegar A. Pregnancy after 40 years of age. Obstet Gynecol 1986;68:452–4.
17. Brassil MJ, Turner MJ, Egan DM, MacDonald DW. Obstetric outcome in first-time mothers aged 40 years and over. Eur J Obstet Gynecol Reprod Biol 1987;25:115–20.
18. Lagrew DC Jr, Morgan MA, Nakamoto K, Lagrew N. Advanced maternal age: perinatal outcome when controlling for physician selection. J Perinatol 1996;16:256–60.
19. Chan BC, Lao TT. Influence of parity on the obstetric performance of mothers aged 40 years and above. Hum Reprod 1999;14:833–7.
20. Seoud MA, Nassar AH, Usta IM, Melhem Z, Kazma A, Khalil AM. Impact of advanced maternal age on pregnancy outcome. Am J Perinatol 2002;19:1–8.
21. Ziadeh S, Yahaya A. Pregnancy outcome at age 40 and older. Arch Gynecol Obstet 2001;265:30–3.
22. Bergh T, Ericson A, Hillensjo T, Nygren KG, Wennerholm UB. Deliveries and children born after in-vitro fertilisation in Sweden 1982–95: a retrospective cohort study. Lancet 1999;354:1579–85.
This article has been cited 76 time(s).
Acta PaediatricaAssisted conception, maternal age and breastfeeding: an Australian cohort studyActa Paediatrica
Jognn-Journal of Obstetric Gynecologic and Neonatal NursingPredictors of Perception of Pregnancy Risk among Nulliparous WomenJognn-Journal of Obstetric Gynecologic and Neonatal Nursing
Maternal and Child Health JournalInterpregnancy Intervals and the Risk for Infant Mortality: A Case Control Study of Arizona Infants 2003-2007Maternal and Child Health Journal
ClinicsMaternal morbidity and near miss associated with maternal age: the innovative approach of the 2006 Brazilian demographic health surveyClinics
Swiss Medical WeeklySocial freezing in Switzerland and worldwide - a blessing for women today?Swiss Medical Weekly
MidwiferyMaternal age >= 45 years and maternal and perinatal outcomes: A review of the evidenceMidwifery
Journal of Human HypertensionAssisted reproductive technology and pregnancy-related hypertensive complications: a systematic reviewJournal of Human Hypertension
European Journal of Preventive CardiologyMyocardial infarction in pregnancy and postpartum in the UKEuropean Journal of Preventive Cardiology
Reproductive HealthSociodemographic characteristics of mother's population and risk of preterm birth in ChileReproductive Health
Journal of Maternal-Fetal & Neonatal MedicineOutcome of Twin pregnancy in women >= 45 years old: a retrospective cohort studyJournal of Maternal-Fetal & Neonatal Medicine
Journal of Reproductive and Infant PsychologyThe experience of pregnancy: does age or mode of conception matter?Journal of Reproductive and Infant Psychology
Plos OneCaesarean Delivery and Subsequent Stillbirth or Miscarriage: Systematic Review and Meta-AnalysisPlos One
Bmc Pregnancy and ChildbirthVery advanced maternal age and morbidity in Victoria, Australia: a population based studyBmc Pregnancy and Childbirth
Journal of PathologyReproductive ageing in womenJournal of Pathology
MaturitasMaternal, perinatal and infant outcome of spontaneous pregnancy in the sixth decade of lifeMaturitas
Sajog-South African Journal of Obstetrics and Gynaecology
Ageing motherhood: private grief and public health concern
Sajog-South African Journal of Obstetrics and Gynaecology, 13(1):
International Journal of Gynecology & ObstetricsEffect of parity and advanced maternal age on obstetric outcomeInternational Journal of Gynecology & Obstetrics
Obstetrics and GynecologyImpact of maternal age on obstetric outcomeObstetrics and Gynecology
European Journal of Obstetrics & Gynecology and Reproductive BiologyAdvanced maternal age and adverse perinatal outcomes in an Asian populationEuropean Journal of Obstetrics & Gynecology and Reproductive Biology
American Journal of Obstetrics and GynecologyPregnancy at or beyond age 40 years is associated with an increased risk of fetal death and other adverse outcomesAmerican Journal of Obstetrics and Gynecology
Journal of Obstetrics and GynaecologyPregnancy outcome after age 40 and risk of low birth weightJournal of Obstetrics and Gynaecology
MaturitasMaternal and perinatal risks for women over 44-A reviewMaturitas
Hypertensive Disorders in Pregnancy: A 5-year Analysis of the Wartime and Postwar Period in South-Western Region of Bosnia and Herzegovina
Collegium Antropologicum, 33():
Journal of Womens HealthPregnancy late in life: A hospital-based study of birth outcomesJournal of Womens Health
PediatricsExplaining the Low Risk of Preterm Birth Among Arab Americans in the United States: An Analysis of 617 451 BirthsPediatrics
Human ReproductionThe aged uterus: multifetal pregnancy outcome after ovum donation in older womenHuman Reproduction
Journal of Adolescent HealthJoint Effect of Obesity and Teenage Pregnancy on the Risk of Preeclampsia: A Population-Based StudyJournal of Adolescent Health
Seminars in Reproductive MedicineContraception for Specific PopulationsSeminars in Reproductive Medicine
Journal of Reproductive Medicine
Fertility and a woman's age
Journal of Reproductive Medicine, 51(3):
American Journal of PerinatologyAdvanced maternal age is an independent risk factor for intrauterine growth restrictionAmerican Journal of Perinatology
Acta Obstetricia Et Gynecologica ScandinavicaFirst time mothers' pregnancy and birth experiences varying by ageActa Obstetricia Et Gynecologica Scandinavica
American Journal of Obstetrics and GynecologyDystocia increases with advancing maternal ageAmerican Journal of Obstetrics and Gynecology
Health Care for Women InternationalEffect of Older Maternal Age on the Risk of Spontaneous Preterm Labor: A Population-Based StudyHealth Care for Women International
American Journal of Obstetrics and GynecologyGenetic epidemiologic studies of preterm birth: guidelines for researchAmerican Journal of Obstetrics and Gynecology
Best Practice & Research in Clinical Obstetrics & GynaecologyAgeing and ART: a waste of time and money?Best Practice & Research in Clinical Obstetrics & Gynaecology
Effects of impending ovarian failure induced by 4-vinylcyclohexene diepoxide on fertility in C57BL/6 female mice
Comparative Medicine, 57(5):
European Journal of Obstetrics Gynecology and Reproductive BiologyAuthors' response to comment on "Pregnancy outcome in primiparae of advanced maternal age" Eur J Obstet Gynecol Reprod Biol; in pressEuropean Journal of Obstetrics Gynecology and Reproductive Biology
Human ReproductionPerinatal outcome of twin pregnancies in women of advanced ageHuman Reproduction
American Journal of PerinatologyAdvanced Maternal Age. Part I: Obstetric ComplicationsAmerican Journal of Perinatology
Journal De Gynecologie Obstetrique Et Biologie De La ReproductionImpact of advanced maternal age on fecundity and women's and children's healthJournal De Gynecologie Obstetrique Et Biologie De La Reproduction
European Journal of Medical Research
Impact of Maternal Body Mass Index on Neonatal Outcome
European Journal of Medical Research, 14(5):
Human Reproduction UpdatePaternal age and reproductionHuman Reproduction Update
British Medical Journal
Which career first? The most secure age for childbearing remains 20-35
British Medical Journal, 331():
Maternal and Child Health JournalFactors influencing childbearing decisions and knowledge of perinatal risks among Canadian men and womenMaternal and Child Health Journal
Journal of Maternal-Fetal & Neonatal MedicineMaternal serum soluble CD30 is increased in normal pregnancy, but decreased in preeclampsia and small for gestational age pregnanciesJournal of Maternal-Fetal & Neonatal Medicine
Journal of Epidemiology and Community HealthIncrease in maternal mortality associated with change in the reproductive pattern in Spain: 1996-2005Journal of Epidemiology and Community Health
Clinical and Experimental Obstetrics & Gynecology
The effect of amniocentesis on preterm delivery rate in women with uterine myoma
Clinical and Experimental Obstetrics & Gynecology, 37(1):
American Journal of Obstetrics and GynecologyIs advanced maternal age an independent risk factor for uteroplacentat insufficiency?American Journal of Obstetrics and Gynecology
Pregnancy and delivery in women over 35 years old
Przeglad Menopauzalny, 8(2):
Journal of Reproductive and Infant PsychologyReasons for infertile couples to discontinue in vitro fertilisation (IVF) treatmentJournal of Reproductive and Infant Psychology
Human Reproduction UpdateFemale contraception over 40Human Reproduction Update
Acta Obstetricia Et Gynecologica ScandinavicaRisk factors for asphyxia associated with substandard care during laborActa Obstetricia Et Gynecologica Scandinavica
European Journal of Obstetrics & Gynecology and Reproductive BiologyExcess of maternal mortality in foreign nationalities in Spain, 1999-2006European Journal of Obstetrics & Gynecology and Reproductive Biology
Pakistan Journal of Medical Sciences
The Comparative Study of Pregnancy Outcomes in Primiparous and Multiparous Women With Increasing Age
Pakistan Journal of Medical Sciences, 26(2):
American Journal of Obstetrics and GynecologyHigher rate of stillbirth at the extremes of reproductive age: A large nationwide sample of deliveries in the United StatesAmerican Journal of Obstetrics and Gynecology
European Journal of Obstetrics Gynecology and Reproductive BiologyPregnancy outcome in primiparae of advanced maternal ageEuropean Journal of Obstetrics Gynecology and Reproductive Biology
Canadian Medical Association JournalMaternal age and risk of stillbirth: a systematic reviewCanadian Medical Association Journal
Human ReproductionAssessing first trimester growth: the influence of ethnic background and maternal ageHuman Reproduction
American Journal of PerinatologyStillbirth at term in women of advanced maternal age in the United States: When could the antenatal testing be initiated?American Journal of Perinatology
Physical Activity and Preterm Birth A Literature Review
Sports Medicine, 39():
Geburtshilfe Und FrauenheilkundePregnancies at an Advanced Maternal Age: Results From Zurich and Review of the LiteratureGeburtshilfe Und Frauenheilkunde
American Journal of Obstetrics and GynecologyMaternal age and the risk of stillbirth throughout pregnancy in the United StatesAmerican Journal of Obstetrics and Gynecology
Jognn-Journal of Obstetric Gynecologic and Neonatal NursingTailoring peripartum nursing care for women of advanced maternal ageJognn-Journal of Obstetric Gynecologic and Neonatal Nursing
Journal of PediatricsMaternal Age, Multiple Birth, and Extremely Low Birth Weight InfantsJournal of Pediatrics
Canadian Medical Association JournalAdvanced maternal age: Are decisions about the timing of child-bearing a failure to understand the risks?Canadian Medical Association Journal
American Journal of Obstetrics and GynecologyEtiology and prevention of stillbirthAmerican Journal of Obstetrics and Gynecology
Paediatric and Perinatal Epidemiology
Maternal age and parity-associated risks of preterm birth: differences by race/ethnicity
Paediatric and Perinatal Epidemiology, 21(1):
Canadian Medical Association JournalSocioeconomic status and perinatal outcomes in a setting with universal access to essential health care servicesCanadian Medical Association Journal
American Journal of Obstetrics and GynecologyDoes length of labor vary by maternal age?American Journal of Obstetrics and Gynecology
Fertility and SterilityObstetric outcomes in donor oocyte pregnancies compared with advanced maternal age in in vitro fertilization pregnanciesFertility and Sterility
Reproduction Fertility and DevelopmentAltered pregnancy outcomes in mice following treatment with the hyperglycaemia mimetic, glucosamine, during the periconception periodReproduction Fertility and Development
Current Opinion in Obstetrics and GynecologyIncreased risk in the elderly parturientCurrent Opinion in Obstetrics and Gynecology
Obstetrics & GynecologySocioeconomic Status and Receipt of Obstetric Services in CanadaObstetrics & Gynecology
Obstetrics & GynecologyThe Perinatal Effects of Delayed ChildbearingObstetrics & Gynecology
Obstetrics & GynecologyPregnancy Outcome After Age 50Obstetrics & Gynecology
© 2004 by The American College of Obstetricians and Gynecologists.
What does "Remember me" mean?
By checking this box, you'll stay logged in until you logout. You'll get easier access to your articles, collections,
media, and all your other content, even if you close your browser or shut down your
To protect your most sensitive data and activities (like changing your password),
we'll ask you to re-enter your password when you access these services.
What if I'm on a computer that I share with others?
If you're using a public computer or you share this computer with others, we recommend
that you uncheck the "Remember me" box.
Looking for ABOG articles? Visit our ABOG MOC II collection. The selected Green Journal articles are free through the end of the calendar year.
ACOG MEMBER SUBSCRIPTION ACCESS
If you are an ACOG Fellow and have not logged in or registered to Obstetrics & Gynecology, please follow these step-by-step instructions to access journal content with your member subscription.
Data is temporarily unavailable. Please try again soon.
Readers Of this Article Also Read