Maternal and neonatal outcomes of spontaneously conceived pregnancies in mothers over 45 years: a review of the literature

Risk of Preterm Delivery in Very Advanced Maternal Age Parturients Utilizing In Vitro Fertilization

OBJECTIVE

Among patients ≥45 years, the birth rate in the United States continues to increase. As fertility declines with age, this cohort often utilizes assisted reproductive technology, specifically in vitro fertilization (IVF). While both advancing maternal age and IVF are independently associated with adverse maternal outcomes, data regarding their additive effect are scant. This article aims to determine if patients who conceive via IVF are at increased risk for preterm birth (PTB) compared to patients with non-IVF pregnancies in a very advanced maternal age (vAMA) cohort (≥45 years).

STUDY DESIGN

Retrospective cohort study of all pregnant patients ≥45 years old who delivered at a single institution (2014-2021). Those with incomplete delivery/neonatal records or multiples beyond twins were excluded. We compared individuals who conceived via IVF to those who conceived without IVF. The primary outcome was preterm delivery <37 weeks gestation. Secondary outcomes included other adverse perinatal outcomes. Using multivariable logistic regression, we adjusted for multiple gestation as well as confounders found to be significantly different in the univariable analysis and other known risk factors for PTB.

RESULTS

In our study cohort of 420 vAMA patients, individuals who underwent IVF were more likely to be older, privately insured, nulliparous, and with a twin gestation. The PTB rate in vAMA patients who underwent IVF was 24.4 compared to 8.4% in patients who did not use IVF (p < 0.001). After adjusting for confounders, IVF was an independent risk factor for PTB <37 weeks in vAMA patients (adjusted odds ratio {aOR] = 4.3, 95% confidence interval [CI]: 1.7-10.4, p = 0.001). In vitro fertilization was also associated with a composite of adverse maternal outcomes (hypertensive disorder of pregnancy, postpartum hemorrhage, blood transfusion, and unplanned hysterectomy) (aOR = 1.7, 95% CI: [1.1-2.9], p = 0.03).

CONCLUSION

In the vAMA population, conception via IVF is associated with an increased risk of PTB <37 weeks.

KEY POINTS

· This study examines IVF as an independent risk factor for PTB in patients ≥45 years at delivery, which has not been specifically addressed in prior studies.. · In vAMA patients, use of IVF is associated with an increased risk of PTB <37 weeks. These patients also have higher rates of cesarean delivery. Neonates from IVF pregnancies are more likely to be very low birth weight or low birth weight.. · Bodies of research exist for both advanced maternal age and assisted reproductive technology, there is a paucity of data specifically in parturients of vAMA who conceive via IVF..

Iatrogenic factors contributed to the high rate of preterm birth in a community hospital

BACKGROUND

Preterm birth (PTB) rates have been increased significantly in recent years, mostly due to obstetric intervention. This study presents the incidence of PTB in community hospitals by assessing the association between pregnancy complications and iatrogenic PTB.

METHODS

A total of 6,693 pregnancies were enrolled in the Wuxi Maternity and Child Health Care Hospital of Nanjing Medical University. They were divided into two groups (<35 and ≥35 years of age) to examine the effect of maternal age on PTB. Binary logistic and multiple linear regression analyses were used to assess the relationship between PTB and pregnancy complications.

RESULTS

This study provided the incidence of PTB and found that PP, PROM, and ICP increased the risk of PTB, indicating that pregnancy complications have led to the iatrogenic PTB and contributed to the high rate of PTB, especially in the group of advanced-age pregnant women. The prevalence of PTB was 9.53%. Placenta previa (PP), premature rupture of membranes (PROM), and intrahepatic cholestasis of pregnancy (ICP) were significantly associated with PTB. Among all the risk factors, hypertension, disease in pregnancy, premature PROM, and PP were observed as independent key factors for iatrogenic PTBs. In the advanced-age group, PP and pPROM increased the risk of PTB.

CONCLUSIONS

It is often necessary to terminate a pregnancy in community hospitals to balance the safety of the fetus and the maternal comorbid symptoms, which has led to nosocomial premature delivery. Therefore, high-risk pregnancies should be carefully evaluated and comprehensively treated with caution to balance the preterm rate and the safety of the pregnant woman and fetus, and the pros and cons of the outcomes, which has brought a challenge to an obstetrician to reduce the proportion of iatrogenic PTB.

Risk Factors for Adverse Pregnancy Outcomes among Zhuang Ethnic Pregnant Women: A Cohort Study in Guangxi, China

Risk factors for adverse pregnancy outcomes among Zhuang ethnic pregnant women are unclear. This study analyzed the incidence and risk factors related to preterm birth (PB), low birth weight (LBW) and macrosomia in Zhuang population. We conducted a prospective cohort study of 9965 Zhuang pregnancy women in Guangxi, China. Information on mothers and newborns was obtained by using questionnaires and referring to medical records. Multivariate logistic regression analyses were used to evaluate the association between related factors and adverse pregnancy outcomes. Our results showed that the incidence of PB, LBW and macrosomia in Zhuang people was 5.55%, 5.64% and 2.19%, respectively. Maternal age ≥36 years (OR=2.22, 95% CI: 1.51-3.27) was related to a higher incidence of PB. Those with pre-pregnancy body mass index (BMI) <18.5 kg/m2 (OR=1.91, 95% CI: 1.45-2.51), and had a female fetus (OR=1.74, 95% CI: 1.36-2.23) were more likely to have LBW infants. Maternal age between 31 and 35 years (OR=1.76, 95% CI: 1.03-2.99) and pre-pregnancy overweight or obesity (OR=1.79, 95% CI: 1.15-2.80) were associated with a higher risk of macrosomia. The protective factors of macrosomia were maternal pre-pregnancy BMI <18.5 kg/m2 (OR=0.30, 95% CI: 0.15-0.60) and female fetus (OR=0.41, 95% CI: 0.28-0.59). Our study provided a reference for maternal and childcare administration among Zhuang population.

Maternal air pollution exposure and preterm birth in Wuxi, China: Effect modification by maternal age

BACKGROUND

Numerous studies have investigated prenatal air pollution and shown that air pollutants have adverse effect on birth outcomes. However, which trimester was the most sensitive and whether the effect was related to maternal age is still ambiguous.

OBJECTIVES

This study aims to explore the association between maternal air pollution exposure during pregnancy and preterm birth, and if this relationship is modified by maternal age.

METHODS

In this retrospective cohort study, we examine the causal relationship of prenatal exposure to air pollutants including particulate matters, which are less than 10 µm (PM₁₀), and ozone (O₃), which is one of the gaseous pollutants, on preterm birth by gestational age. A total of 6693 pregnant women were recruited from Wuxi Maternal and Child Health Care Hospital. The participants were dichotomized into child-bearing age group (< 35 years old) and advanced age group (> = 35 years old) in order to analyze the effect modification by maternal age. Logistic and linear regression models were performed to assess the risk for preterm birth (gestational age < 37 weeks) caused by prenatal air pollution exposure.

RESULTS

With adjustment for covariates, the highest level of PM₁₀ exposure significantly increased the risk of preterm birth by 1.42-fold (95% CI: 1.10, 1.85) compared those with the lowest level in the second trimester. Trimester-specific PM₁₀ exposure was positively associated with gestational age, whereas O₃ exposure was associated with gestational age in the early pregnancy. When stratified by maternal age, PM₁₀ exposure was significantly associated with an increased risk of preterm birth only in the advanced age group during pregnancy (OR:2.15, 95% CI: 1.13, 4.07). The results suggested that PM₁₀ exposure associated with preterm birth was modified by advanced maternal age (OR _interaction = 2.00, 95% CI: 1.02, 3.91, P_interaction = 0.032).

CONCLUSION

Prenatal air pollution exposure would increase risk of preterm birth and reduced gestational age. Thus, more attention should be paid to the effects of ambient air pollution exposure on preterm birth especially in pregnant women with advanced maternal age.

The Effect of Very Advanced Maternal Age on Maternal and Neonatal Outcomes: A Systematic Review

OBJECTIVE

To summarize information on the maternal and perinatal outcomes among pregnant women with a maternal age greater or equal to 45 years old compared with women with a maternal age of less than 45.

METHODS

A comprehensive systematic search of online databases from January 1946 through June 2015 was completed. The maternal outcomes were: fetal loss, preterm birth, full-term birth, complications of pregnancy, the type of delivery, and periconception hemorrhage. The fetal outcomes were: intrauterine growth restriction/LGA, fetal anomalies, APGAR score, and neonatal death.

RESULTS

Twenty articles were included in the systematic review and 15 included in the meta-analysis. There was a 2.60 greater likelihood of fetal loss (I² = 99%). Newborns of women of a very advanced maternal age were 2.49 more likely to have a concerning 5-minute APGAR score. Very advanced maternal age women had a 3.32 greater likelihood of pregnancy complications (I² = 91%). There was a 1.96 greater likelihood of preterm birth at very advanced maternal age (I² = 91%) and a 4 times greater likelihood of having to deliver through Caesarean section (I² = 97%).

CONCLUSION

This systematic review showed an increased risk of adverse maternal and perinatal outcomes. The large amount of heterogeneity among most outcomes that were investigated suggest results must be interpreted with caution.

Gestación y parto en mujeres con edad materna avanzada en Tunja, Colombia. 2011-2015

Introducción. La gestación en mujeres >35 años se considera una condición de riesgo obstétrico, tanto para la madre como para el feto.Objetivo. Explorar la prevalencia y los factores determinantes asociados con la gestación en mujeres >35 años en Tunja.Materiales y métodos. Estudio de corte transversal en el que se analizó el registro institucional de partos ocurridos en mujeres residentes en Tunja durante el período 2011-2015.Resultados. Se presentaron 1 558 partos en >35 años, lo que constituye el 11.6-13% del total anual; 49.8% de los partos se dieron mediante cesárea. Los factores asociados fueron afiliación al régimen contributivo, escolaridad de la gestante y de su pareja, hábitat urbano y pareja estable. No se encontró riesgo incrementado de complicaciones obstétricas en comparación con otros grupos de edad, pero sí asociación positiva con mayor probabilidad de prematurez, sobrepeso, óbito fetal previo y operación cesárea.Conclusiones. La incidencia de parto es ligeramente mayor a la media nacional, quizás por factores sociales y culturales no establecidos con plenitud, pero similares a los reportados en la literatura. Es recomendable profundizar en el análisis de determinantes para mejorar las estrategias de vigilancia y control, así como rutinas de tamizaje.

Maternal and neonatal outcomes in advanced maternal age: a retrospective cohort study

OBJECTIVES

To describe the effect of extremely advanced maternal age (EAMA) on maternal/neonatal outcomes.

METHODS

This was a case-control study in which 127 women ≥40 years at the time of delivery out of 2853 singleton hospital deliveries in Ondokuz Mayis University between 1 January 2008 and 31 August 2010 constituted the study group. One hundred and twenty-seven else were chosen randomly out of 2412, 21-35 years old women, via a computer system as controls. Demographic features of 254 mothers and infants as well as maternal and neonatal complications were recorded.

RESULTS

Mean maternal age was 41.5 ± 1.9 (40-49) years in EAMA group and 28.9 ± 4.2 (21-35) years in controls. Primigravidity was 19.6% in the EAMA group, whereas 37.8% in controls (p = 0.003). No difference was found between groups according to route of delivery, stillbirth, preterm birth, congenital abnormalities, gender of babies, NICU admission and respiratory problems (for all p > 0.05). A 5th min Apgar score <7 was more frequent in babies born to EAMA mothers compared to controls (9.8% versus 4.9%, p = 0.004).

CONCLUSION

The present study shows that EAMA mothers and their offsprings have similar peri and neonatal risks compared to younger mothers, except lower 5th minute Apgar scores. We conclude that with good perinatal care, EAMA women and their babies can pass through the perinatal period with similar risks of younger women.

Maternal aging affects life performance of progeny in a Holstein dairy cow model

The development and life performance of 404 high-producing Holstein dairy cows was studied from birth onwards and during two lactations. The management, environment and parental genetics of the cows were known in detail. Cluster analysis identified four performance ‘types’: high-yielding (HY) cows and persistently high-yielding (PHY) cows, which accounted for 33% of the animals; medium-yielding (MY) cows, 41%; and low-yielding (LY) cows, 26%. Prenatal determinants of the life performance of the progeny were analyzed. Developmental and environmental factors were excluded as determinants of performance (including birth weight, level of passive immunity transfer, growth rate, age at first parturition and reproductive efficiency). Life performance did show minor seasonal effects, with more HY cows but less PHY being born during the cold season (90.1% in HY; 58.3% in PHY v. 81.5%). Instead, the single most important factor influencing life performance of daughters was maternal age. HY cows were born from the youngest mothers (1.89±1.14 parturitions, 3.12±1.42-year old), whereas LY cows were born from the oldest (2.72±1.80 parturitions, 3.97±2.01-year old; P<0.001). Life performance of the dams did not differ among clusters. In addition, metabolic parameters (fat and protein yield) were found to correlate significantly with yields between the first and second lactations (milk yield: r=0.357; fat yield: r=0.211; protein yield: r=0.277; P<0.0001), suggesting the influence of the individual. These results suggest that under optimal health, nutritional and environmental conditions, maternal aging is an important determinant of the life performance of progeny and argue for the need to identify conditions that contribute to health and disease in progeny according to the Developmental Origin of Health and Disease or DOHaD concept. Our findings may help the development of novel management guidelines for dairy farms.