Effect of advanced maternal age on maternal and neonatal outcomes in assisted reproductive technology pregnancies

The interaction effect of pre-pregnancy body mass index and maternal age on the risk of pregnancy complications in twin pregnancies after assisted reproductive technology

OBJECTIVE

The widespread use of assisted reproductive technology (ART) has led to an increased twin pregnancy rate and increased risk of pregnancy complications. Pre-pregnancy body mass index (BMI) and maternal age are both risk factors for pregnancy complications. This study aimed to explore whether there is an interaction effect between pre-pregnancy BMI and maternal age on pregnancy complications in women with twin pregnancies after ART.

METHODS

Data of 445,750 women with twin pregnancies after ART were extracted from the National Vital Statistics System (NVSS) database in 2016-2021 in this retrospective cohort study. Univariate and multivariate logistic regression analyses were used to explore (1) the associations between pre-pregnancy BMI, maternal age, and total pregnancy complications; (2) interaction effect between pre-pregnancy BMI and maternal age on total pregnancy complications; and (3) this interaction effect in parity, race, gestational weight gain (GWG), and preterm birth subgroups. The evaluation indexes were odds ratios (ORs), relative excess risk of interaction (RERI), attributable proportions of interaction (AP), and synergy index (S) with 95% confidence intervals (CIs).

RESULTS

A total of 6,827 women had pregnancy complications. After adjusting for the covariates, compared with women had non-AMA and pre-pregnancy BMI <25 kg/m2, higher maternal age combined with higher pre-pregnancy BMI was associated with higher odds of total pregnancy complications [OR = 2.16, 95%CI: (1.98-2.36)]. The RERI (95% CI) was 0.22 (0.04-0.41), AP (95% CI) was 0.10 (0.02-0.19), and S (95% CI) was 1.24 (1.03-1.49). Subgroup analysis results indicated that the potential additive effect between pre-pregnancy BMI and maternal age on total pregnancy complications was also found in women with different race, multipara/unipara, GWG levels, or preterm births/non-preterm births (all p < 0.05).

CONCLUSION

Pre-pregnancy BMI and maternal age may have an additive effect on the odds of pregnancy-related complications in women with twin pregnancy after ART.

Diminished ovarian reserve causes adverse ART outcomes attributed to effects on oxygen metabolism function in cumulus cells

BACKGROUND

Declining oocyte quality in women with advanced age has been a major impediment to assisted reproductive treatments' (ART) success rate. However, aging is often accompanied by a diminished ovarian reserve (DOR). Cumulus cells (CCs) are known to play an important role in the development and maturation of oocytes, and the quality of CCs actually reflects the quality of the oocyte. In this study, CCs were used to investigate the real reasons for the decline in oocyte quality in older women.

METHODS

Ninety-nine CC samples were subdivided into 4 different groups according to the different age and ovarian reserve status. Other than clinical ART results, transcriptional expression profiles were performed in CCs to detect the differences.

RESULTS

The results were that DOR, no matter in young or advanced age group, was found to be significantly associated with adverse ART outcomes. Of note, there were no statistically significant changes in ART outcomes in the group at advanced age with normal ovarian reserve (NOR), compared to the young with NOR. DOR induced a series of transcriptional variations in CCs commonly enriched in oxygen metabolism.

CONCLUSION

Our results revealed that the ART outcomes in advanced patients were attributable to the DOR. The oxygen metabolic changes may interfere with CCs' function of supporting oocytes. This study can provide guidance for ART practice that not age but ovarian reserve status is the main predictor for ART outcomes, and ovarian reserve status should be timely assessed when the clinical manifestations are still mild in elderly women.

How does IVF conception affect pregnancy complications in an older cohort of women, at least 38 years of age? Study of a population database

PURPOSE

To compare perinatal outcomes in in-vitro fertilization (IVF) pregnancies versus spontaneous conceptions in woman of advanced maternal age (AMA), and to evaluate the effect of increasing age on IVF pregnancies' outcomes.

METHODS

A retrospective population-based cohort study including pregnant women who delivered between 2008-2014 in the US. First, we included women aged 38-43 years and compared those with IVF conceptions (cases) to women with spontaneous conceptions (controls). Thereafter, we compared IVF pregnancies in women aged 38-43 years to IVF pregnancies at < 38 years of age. Multivariate logistic regression was performed to compare both groups regarding pregnancy,delivery, and neonatal outcomes after adjusting for plausible confounders.

RESULTS

Three hundred nine thousand five hundred sixty-seven pregnant women aged 38-43 years were identified, with 2,762 composing the IVF group, and 306,805 composing the control group. After adjusting for confounders, the IVF group had a higher risk of several adverse obstetrical outcomes, including hypertensive disorders of pregnancy (aOR 1.31,95%CI 1.06-1.62), gestational diabetes (aOR 1.26,95%CI 1.13-1.41),preterm delivery (aOR 1.45,95%CI 1.16-1.81), cesarean section (CS) (aOR 1.84,95%CI 1.55- 2.19),postpartum hemorrhage (aOR 1.68,95%CI 1.27- 2.24), and maternal infection (aOR 1.90,95%CI 1.31-2.77), with comparable neonatal outcomes. For the second analysis, 9712 IVF pregnancies were included (n = 6950 < 38 years, and n = 2762 ≥ 38 years). Women ≥ 38 years who underwent IVF were more likely to experience hypertensive disorders of pregnancy, CS, hysterectomy and blood transfusion, with comparable neonatal outcomes.

CONCLUSION

IVF AMA pregnancies have a significant increase in myriad perinatal complications compared to spontaneous AMA pregnancies. Younger women undergoing IVF have mildly less complications than their older counterparts.

Influence of maternal age on the birthweight of infants delivered from frozen-thawed blastocyst transfer cycles

The aim of this study was to investigate whether maternal age had an effect on the birthweight of singletons delivered from frozen-thawed blastocyst transfer (FBT) cycles. A total of 1203 FBT cycles occurring between July 2011 and June 2021 at a single centre were retrospectively analysed. Based on the maternal age at FBT, the patients were divided into four groups: <30, 30-34, 35-37, and ≥38 years of age. Main outcomes measured included singleton birthweights, preterm births, large-for-gestational-age (LGA) and small-for-gestational-age (SGA) live births among the groups. There was no significant difference in birth weight among the four groups, while the highest birth weight was found in the <30 years group. The incidence of very preterm births and very low birth weights demonstrated an increasing trend with age; on the contrary, the incidence of preterm births, low birth weight (LBW), high birth weight and LGA and SGA live births gradually decreased with increasing age, but these differences were not statistically significant among groups (P>0.05, respectively). Although the proportion of females was lower than that of males, the difference was not statistically significant among the groups. After adjusting for possible confounders, maternal age was found to have no effect on adverse neonatal outcomes in the regression analyses (P>0.05). Birthweight in singleton births from FBT was not affected by maternal age.

Pregnancy outcomes at maternal age over 45 years: a systematic review and meta-analysis

OBJECTIVE

This study aimed to identify trends in pregnancy outcomes, especially delivery mode, among pregnant patients older than 45 years.

DATA SOURCES

A literature search was performed using PubMed, Web of Science, and the Cochrane Central Register of Controlled Trials for studies published between January 1, 2010, and June 30, 2022.

STUDY ELIGIBILITY CRITERIA

The primary outcomes were cesarean delivery and assisted delivery. The secondary outcomes were preeclampsia, gestational diabetes mellitus, placenta previa, placental abruption, postpartum hemorrhage, and preterm birth. The inclusion criteria were studies examining the relationship between older age pregnancy and pregnancy outcomes, studies that compared pregnancy outcomes at maternal age ≥45 years and <45 years, and at least one of the primary and secondary pregnancy outcomes were included.

METHODS

Study screening was performed after duplicates were identified and removed. The quality of each study and publication bias were assessed. Forest plots and I² statistics were calculated for each study outcome for each group. The main analysis was a random-effects analysis. The inverse variance method was used to integrate the results if studies had an adjusted analysis.

RESULTS

Among 4209 studies initially retrieved, 24 were included in this review. All studies were retrospective, observational studies. Pregnant patients aged ≥45 years had a significantly higher cesarean delivery rate (odds ratio, 2.87; 95% confidence interval, 2.50-3.30; I²=97%) than those aged <45 years. However, the emergency cesarean delivery rate was lower in older pregnant patients (odds ratio, 0.61; 95% confidence interval, 0.47-0.79; I²=79%). Pregnancy in older individuals was associated with a lower assisted delivery rate than pregnancy in younger individuals (odds ratio, 0.85; 95% confidence interval, 0.75-0.97; I²=48%). Preeclampsia, gestational diabetes mellitus, placenta previa, placental abruption, postpartum hemorrhage, and preterm birth were more likely to occur in pregnant patients aged ≥45 years than in those aged <45 years. Adjusted pooled analyses showed trends similar to those in the unadjusted pooled analyses.

CONCLUSION

Adverse pregnancy outcomes, typically cesarean delivery, were more likely to occur in older (≥45 years) pregnant patients than in younger pregnant patients. However, the assisted delivery rate was lower in older pregnant patients.

Is the Occurrence of Gestational Diabetes Mellitus in Pregnancies Higher Following In Vitro Fertilization Treatment? Why? A Retrospective Cohort Study

Purpose: This study aim to determine the occurrence of gestational diabetes mellitus (GDM) in pregnancies after IVF treatment and to evaluate the factors that reduce this risk. Methods: This retrospective cohort study was conducted using the medical records of pregnant women who conceived following IVF at the in-vitro fertilization center between 2002–2019. The data were obtained from medical records and phone interviews. Univariate and multivariate logistic regression analyses were performed. Results: The incidence of GDM was found to be 16.7%. The regression model indicated that the risk of GDM was 4.57 times higher in the age group 36–40 at conception during the IVF cycle than the age group 31–35 (95% CI = 1.18–17.73, p = .028). Furthermore, women who conceived after the second IVF trial had a risk of GDM 3.464 times higher than those that conceived after their first IVF trial (95% CI = 1.07–11.23, p= .038). Conclusion: As age and number of IVF trials increase in infertile women, the risk of GDM increases after IVF treatment.

Effect of advanced parental age on pregnancy outcome and offspring health

PURPOSE

Fertility at advanced age has become increasingly common, but the aging of parents may adversely affect the maturation of gametes and the development of embryos, and therefore the effects of aging are likely to be transmitted to the next generation. This article reviewed the studies in this field in recent years.

METHODS

We searched the relevant literature in recent years with the keywords of "advanced maternal/paternal age" combined with "adverse pregnancy outcome" or "birth defect" in the PubMed database and classified the effects of parental advanced age on pregnancy outcomes and birth defects. Related studies on the effect of advanced age on birth defects were classified as chromosomal abnormalities, neurological and psychiatric disorders, and other systemic diseases. The effect of assisted reproduction technology (ART) on fertility in advanced age was also discussed.

RESULTS

Differences in the definition of the range of advanced age and other confounding factors among studies were excluded, most studies believed that advanced parental age would affect pregnancy outcomes and birth defects in offspring.

CONCLUSION

To some extent, advanced parental age caused adverse pregnancy outcomes and birth defects. The occurrence of these results was related to the molecular genetic changes caused by aging, such as gene mutations, epigenetic variations, etc. Any etiology of adverse pregnancy outcomes and birth defects related to aging might be more than one. The detrimental effect of advanced age can be corrected to some extent by ART.

Advanced Maternal Age and Its Association With Cardiovascular Disease in Later Life

INTRODUCTION

Fertility among women at advanced maternal age (AMA) is increasing at a rapid rate in the United States. Although much is known about the impact of older maternal age on the risk for proximate adverse pregnancy outcomes, it is unclear whether older maternal age affects subsequent health. The objective of this study was to evaluate whether AMA is associated with cardiovascular disease (CVD) later in life, adjusting for important social and health factors related to maternal age.

METHODS

Data were obtained from the Nurses' Health Study II, a longitudinal prospective cohort study. We investigated whether women with an AMA first or subsequent birth were at higher risk for developing CVD (myocardial infarction or stroke) after age 42 than women without births at AMA. Cox proportional hazard models were estimated to evaluate this association, adjusting for demographic, fertility, and health characteristics.

RESULTS

A total of 5,471 women (7.7%) in the sample had a first birth at an AMA and 1,282 (1.8%) developed CVD at age 42 or older. Women with first births at AMA had a 26% lower unadjusted hazard of CVD than women not at an AMA during their first birth (hazard ratio, 0.74; 95% confidence interval, 0.57-0.95). This association was attenuated (hazard ratio, 0.80; 95% confidence interval, 0.62-1.05) and no longer significant after adjustment for covariates; the modest association remained significant for women with any AMA birth.

CONCLUSIONS

We found no evidence that AMA births were associated with increased risk for developing CVD later in life in this sample.

Impact of Maternal Age on Singleton Birthweight in Frozen Embryo Transfer Cycles

BACKGROUND

Previous studies have investigated the effect of maternal age on assisted reproductive technology success rates. However, little is known about the relationship between maternal age and neonatal birthweight in frozen embryo transfer (FET) cycles. Whether maternal age influences singleton birthweight in FET cycles remains to be elucidated.

METHODS

This study was conducted at a tertiary care center, involving singleton live births born to women undergoing frozen-thawed embryo transfer during the period from January 2010 to December 2017. A total of 12,565 women who fulfilled the inclusion criteria were enrolled and grouped into four groups according to the maternal age: <30, 30-34, 35-39, and ≥40 years old. A multivariable linear regression analysis was conducted to reveal the relationship between maternal age and neonatal birthweight with controlling for a number of potential confounders.

RESULTS

The highest proportions of low birthweight (LBW, 4.1%), high birthweight (1.2%), preterm birth (PTB, 5.9%), and very PTB (0.9%) were found in the group over 40 years old, but no significant difference was observed among the four groups. Additionally, the 35-39-year-old group had the highest rate of very LBW (0.6%), whereas the 30-34-year-old group had the lowest rate of small for gestational age (SGA, 2.7%). However, multivariate analyses revealed that neonatal outcomes including PTB, LBW, and SGA were similar between the different maternal age groups.

CONCLUSION

Grouping with different maternal age was not associated with mean birthweight and Z-scores of singletons resulting from FET.

The Influence of Increased Prepregnancy Body Mass Index and Excessive Gestational Weight Gain on Pregnancy Course and Fetal and Maternal Perinatal Outcomes

Background: The aim of our study was to assess the influence of prepregnancy Body Mass Index (BMI) changes as well as excessive gestational weight gain (GWG) on maternal and fetal perinatal parameters. Furthermore, we aimed to analyze the influence of increased prepregnancy BMI values and excessive GWG on neonatal early motoric development. Methods: The 203 eligible female participants were evaluated. Prepregnancy Body Mass Index (BMI) and excessive gestational weight gain (GWG) defined according to Institute of Medicine 2009 guidelines in the USA were assessed with tested maternal and fetal perinatal parameters and infants early motoric development (Alberta Infant Motor Scale—AIMS). Results: Significant predictors of increased prepregnancy BMI in perinatal period include: weight at delivery (p = 0.001), GWG (p = 0.002) and BMI at delivery (p < 0.001), while significant predictors of excessive GWG in perinatal period are: prepregnancy BMI (p = 0.029) and BMI at delivery (p < 0.001). In the group of participants with both increased prepregnancy BMI and excessive GWG versus others, significant predictors were: hypertension (HTA) (p = 0.019), amniotic fluid index (AFI) (p = 0.047), Pronation (AIMS) (p = 0.028) and Supination (AIMS) (p = 0.029). Conclusion: Increased prepregnancy BMI and excessive GWG are significantly associated with numerous perinatal factors that could alter the pregnancy course, pregnancy outcome and early motoric development of newborn. Moreover, increased prepregnancy BMI is shown to be a significant predictor of excessive GWG; thus, early selection of pregnant women for close monitoring of weight gain during pregnancy will have positive effects on reducing the risk of less favorable pregnancy course and early motoric development of newborn.

Outcome of two sequential singleton pregnancies and twin pregnancies among primiparous women at advanced age undergoing IVF

PURPOSE

To compare the obstetrical and detailed neonatal outcomes of primipara of advanced maternal age conceiving two sequential singleton pregnancies by IVF with those of primipara conceiving twins by IVF.

METHODS

A retrospective study of all primiparous women aged ≤ 38 years and conceived by IVF who delivered sequential singletons or delivered twins at a single tertiary university affiliated medical center between 2011 and 2019. We performed two main comparisons: 1. First vs. second singleton pregnancies. 2. Two singleton pregnancies vs. twin pregnancies.

RESULTS

Overall, there were 63 women with consecutive singleton IVF pregnancies. The median age was 40.0 at first pregnancy and 42.0 in the second pregnancy. Pregnancy and delivery complications rates did not differ significantly between the first and the second singleton pregnancies, including gestational hypertensive disorders (7 (11.1%) vs. 4 (6.3%), p = 0.530), gestational diabetes mellitus (13 (20.6%) vs 18 (28.5%), p = 0.410), intrauterine growth restriction (6 (9.5%) vs. 4 (6.3%), p = 0.744), or cesarean delivery (25 (39.7%) vs. 29 (46%), p = 0.589). Rates of delivery before 32 weeks gestation were similar for both first and second singleton pregnancies (1.6%, p > 0.999). The proportion of neonatal adverse outcome in both first and second singleton pregnancies groups was low and did not differ between the groups. Compared with women who delivered sequential singletons, women with twin pregnancies had significantly higher cesarean delivery rates (113 (83.7%) vs. 29 (46%), p < 0.001) and lower gestational ages at delivery (36.2 vs. 38.4, p < 0.001) than women with two singleton deliveries. Adverse neonatal outcomes were significantly higher for twin pregnancies, including birthweight < 1500 g (17 (12.6%) vs. 2 (3.2%), p = 0.036), neonatal intensive care unit admission (57 (42.2%) vs. 4 (6.3%), p < 0.001), neonatal hypoglycemia (23 (17%) vs. 3 (4.8%), p = 0.017), and respiratory distress syndrome (14 (10.4%) vs. 1 (1.6%), p = 0.040). Length of neonatal hospitalization was significantly longer for twins (9 vs. 5 days, p < 0.001). The rate of gestational hypertensive disorders (preeclampsia and gestational hypertension) was similar between the groups, but the rates of severe preeclampsia trended higher among women who carried twins (8 (5.9%) vs. 0, p = 0.057).

CONCLUSIONS

Sequential singleton pregnancies at primipara women of advanced maternal age have an overall very good outcome, with no clinically significant difference between the pregnancies. In addition, their outcome is much better compared with twins.

The impact of advanced maternal age on pregnancy outcome

Advanced maternal age is becoming an increasingly relevant issue in high-income developed countries. Lower fertility, greater need for assisted reproductive therapy, and an increase in comorbidities, such as hypertension and diabetes, are some of the reasons for the rise in adverse maternal and fetal outcomes. This chapter reviews and summarizes the recent publications on the impact of advanced maternal age on pregnancy outcomes.

Retrospective Analysis of Obstetric Intensive Care Unit Admissions Reveals Differences in Etiology for Admission Based on Mode of Conception

BACKGROUND

The use of in vitro fertilization is increasing. The incidence of adverse outcomes is greater for women who undergo in vitro fertilization, potentially leading to intensive care unit admission. This study aimed to assess the etiology and course of intensive care unit admission in women who underwent in vitro fertilization compared to those who did not, with specific focus on intensive care unit admission due to postpartum hemorrhage.

METHODS

In this retrospective study, medical records of patients admitted to the intensive care unit during pregnancy or the peripartum period at 2 medical centers (2005-2016 at Mount Sinai Hospital, New York, NY, and 2005-2013 at Shaare Zedek Medical Center, Jerusalem, Israel) were analyzed. Demographic, past medical and obstetric history, and details regarding delivery and intensive care unit stay were collected, as was information regarding mode of conception (in vitro fertilization versus non-in vitro fertilization) for the current pregnancy. The primary outcome measure was difference in etiology of intensive care unit admission between in vitro fertilization and non-in vitro fertilization groups. Secondary outcome measures included differences in prepregnancy characteristics, incidence, severity, and management of postpartum hemorrhage, as well as incidence of other clinical major morbidity events and delivery-related complications. Multivariable logistic regression was performed to study the relationship between in vitro fertilization and the odds of having been admitted to the intensive care unit due to hemorrhage.

RESULTS

During the study period, there were nearly 192,000 deliveries, with 428 pregnant and peripartum women admitted to the intensive care unit. Of the 409 cases analyzed, 60 had conceived following in vitro fertilization and 349 had conceived without in vitro fertilization. The non-in vitro fertilization group was more likely to have multiple medical comorbidities, and the in vitro fertilization group was more likely to have multiple gestations. The groups also differed in etiology of intensive care unit admission; more women in the in vitro fertilization group were admitted due to a pregnancy-related complication. Intensive care unit admission for postpartum hemorrhage was more frequent in the in vitro fertilization group (60.0% vs 43.1%, P = .014), with a 2-fold increase in the incidence of hemorrhagic shock. Logistic regression analysis revealed a 2-fold increase in the odds that intensive care unit admission was due to hemorrhage in women undergoing in vitro fertilization, a finding that was not statistically significant when multiple gestation was added to the model.

CONCLUSIONS

Among patients admitted to the intensive care unit, patients with different modes of conception had dissimilar etiologies for intensive care unit admission with intensive care unit admission due to hemorrhage greater in those with in vitro fertilization. Higher rates of multiple gestation pregnancies may explain this difference. Differences in pregnancies conceived via in vitro fertilization versus without in vitro fertilization may affect the obstetric intensive care unit case mix.