Risk factors of early spontaneous preterm birth despite carrying a cervical pessary in singleton pregnancies with a short cervix: Development of a risk prediction model

Introduction

We aimed to identify the incidence and risk factors of spontaneous preterm birth in pessary carriers with singleton pregnancies and a short cervix in the mid-trimester of pregnancy.

Material and Methods

Patient data were obtained from the PECEP Trial. We analyzed singleton pregnancies in pessary carriers with a short cervix (≤25 mm) between 18 and 22 gestational weeks. Demographics and obstetric history were compared to identify risk factors for spontaneous preterm birth < 34 gestational weeks. Each demographic and obstetric variable was compared between spontaneous preterm birth < 34 and ≥ 34 weeks of gestation.Regression analysis was used to identify risk factors. A risk score model was generated using the odds ratio for significant factors. The risk score model and spontaneous preterm birth risk were assessed using the receiver operating characteristic curve. Perinatal outcomes were compared by risk score.

Results

Among 190 pregnant individuals, 12 (6.3%) had spontaneous preterm birth < 34 gestational weeks. In the bivariate analysis, statistically significant differences between those with and without spontaneous preterm birth were only observed for mean cervical length at diagnosis and mean cervical length after pessary placement. By multiple logistic regression analysis, maternal age (OR 0.818; 95% CI 0.69-0.97; P 0.020), cervical length at diagnosis (OR 0.560; 95% CI 0.43-0.73; P < 0.001) and smoking status (OR 7.276; 95% CI 1.02-51.80; P 0.048) remained significantly associated with spontaneous preterm birth.The ROC curve from the multiple logistic regression analysis, including cervical length, maternal age and smoking status, had an area under the curve (AUC) of 0.952 (P < 0.001). The ROC curve for the risk score model incorporating all three variables had an AUC of 0.864 (95% CI 0.77-0.96; P < 0.001). A high-risk score was predictive of spontaneous preterm birth with a sensitivity of 75%, specificity of 84%, positive predictive value of 24%, and negative predictive value of 98%.Women with a high-risk score had a significantly reduced latency to delivery and poorer neonatal outcomes than those with a low-risk score.

Conclusions

Patients at a high risk for spontaneous preterm birth despite pessary therapy may be identified using cervical length at diagnosis added to maternal age and smoking status.

Exploring preconception health in adolescents and young adults: Identifying risk factors and interventions to prevent adverse maternal, perinatal, and child health outcomes-A scoping review

BACKGROUND

Preconception health provides an opportunity to examine a woman's health status and address modifiable risk factors that can impact both a woman's and her child's health once pregnant. In this review, we aimed to investigate the preconception risk factors and interventions of early pregnancy and its impact on adverse maternal, perinatal and child health outcomes.

METHODS

We conducted a scoping review following the PRISMA-ScR guidelines to include relevant literature identified from electronic databases. We included reviews that studied preconception risk factors and interventions among adolescents and young adults, and their impact on maternal, perinatal, and child health outcomes. All identified studies were screened for eligibility, followed by data extraction, and descriptive and thematic analysis.

FINDINGS

We identified a total of 10 reviews. The findings suggest an increase in odds of maternal anaemia and maternal deaths among young mothers (up to 17 years) and low birth weight (LBW), preterm birth, stillbirths, and neonatal and perinatal mortality among babies born to mothers up to 17 years compared to those aged 19-25 years in high-income countries. It also suggested an increase in the odds of congenital anomalies among children born to mothers aged 20-24 years. Furthermore, cancer treatment during childhood or young adulthood was associated with an increased risk of preterm birth, LBW, and stillbirths. Interventions such as youth-friendly family planning services showed a significant decrease in abortion rates. Micronutrient supplementation contributed to reducing anaemia among adolescent mothers; however, human papillomavirus (HPV) and herpes simplex virus (HSV) vaccination had little to no impact on stillbirths, ectopic pregnancies, and congenital anomalies. However, one review reported an increased risk of miscarriages among young adults associated with these vaccinations.

CONCLUSION

The scoping review identified a scarcity of evidence on preconception risk factors and interventions among adolescents and young adults. This underscores the crucial need for additional research on the subject.

Development and validation of a prediction model on spontaneous preterm birth in twin pregnancy: a retrospective cohort study

BACKGROUND

This study was conducted to develop and validate an individualized prediction model for spontaneous preterm birth (sPTB) in twin pregnancies.

METHODS

This a retrospective cohort study included 3845 patients who gave birth at the Chongqing Maternal and Child Health Hospital from January 2017 to December 2022. Both univariable and multivariable logistic regression analyses were performed to find factors associated with sPTB. The associations were estimated using the odds ratio (OR) and the 95% confidence interval (CI). Model performance was estimated using sensitivity, specificity, accuracy, area under the receiver operating characteristic curve (AUC) and decision curve analysis (DCA).

RESULTS

A total of 1313 and 564 cases were included in the training and testing sets, respectively. In the training set, univariate and multivariate logistic regression analysis indicated that age ≥ 35 years (OR, 2.28; 95% CI 1.67-3.13), pre-pregnancy underweight (OR, 2.36; 95% CI 1.60-3.47), pre-pregnancy overweight (OR, 1.67; 95% CI 1.09-2.56), and obesity (OR, 10.45; 95% CI, 3.91-27.87), nulliparity (OR, 0.58; 95% CI 0.41-0.82), pre-pregnancy diabetes (OR, 5.81; 95% CI 3.24-10.39), pre-pregnancy hypertension (OR, 2.79; 95% CI 1.44-5.41), and cervical incompetence (OR, 5.12; 95% CI 3.08-8.48) are independent risk factors for sPTB in twin pregnancies. The AUC of the training and validation set was 0.71 (95% CI 0.68-0.74) and 0.68 (95% CI 0.64-0.73), respectively. And then we integrated those risk factors to construct the nomogram.

CONCLUSIONS

The nomogram developed for predicting the risk of sPTB in pregnant women with twins demonstrated good performance. The prediction nomogram serves as a practical tool by including all necessary predictors that are readily accessible to practitioners.

Preterm Birth Among Intrapartum Cesarean Deliveries at Public Hospitals in Southern Ethiopia: A Multicenter Retrospective Analysis of Risk Factors

Purpose

Although the underlying causes for preterm birth are thought to be multifactorial irrespective of delivery mode, no study investigated its risk factors amongst cesarean deliveries (CD). Thus, we aimed to identify potential risk factors for the occurrence of preterm birth (PTB) among intrapartum CD.

Methods

Data from 1659 singleton intrapartum CDs were retrospectively recruited using medical records and an obstetric database. Gestational age was calculated using the last menstrual period (LMP) and ultrasound report of early onset pregnancy. A multivariable logistic regression analysis was performed to identify potential risk factors associated with PTB. Odds ratios (ORs) and 95% confidence intervals (95% CI) were used. Statistical analysis was performed using SPSS version 26.0.

Results

In this study, the prevalence of PTB among intrapartum CD was 6.1% (95% CI: 4.9, 7.2%). In the multivariable logistic regression model; grand parity ≥5 (adjusted odds ratio (AOR) = 2.43, 95% CI: 1.72-4.73), maternal age <20 years (AOR=2.63, 95% CI, 1.03-6.71), maternal age ≥35 years (AOR=3.83, 95% CI, 1.49-5.35), cesarean section scar ≥2 (AOR=4.86, 95% CI: 2.68-8.94), antepartum hemorrhage (AOR=4.37, 95% CI: 2.22-8.63), pregnancy-induced hypertension (AOR=2.92, 95% CI: 1.41-6.04), and premature rupture of membranes (AOR=4.56; 95% CI: 1.95-10.65) were significantly associated with PTB.

Conclusion

The current study showed an association between PTB and a multitude of obstetric variables, including grand parity ≥5, CS scar ≥2, antepartum hemorrhage, pregnancy-induced hypertension, and premature rupture of the membrane. Understanding these factors could help to implement improved quality of obstetric and neonatal care to increase survival and reduce morbidity among preterm birth.

Maternal age and the risk of low birthweight and pre-term delivery: a pan-Nordic comparison

BACKGROUND

Advanced maternal age at birth is considered a risk factor for adverse birth outcomes. A recent study applying a sibling design has shown, however, that the association might be confounded by unobserved maternal characteristics.

METHODS

Using total population register data on all live singleton births during the period 1999-2012 in Denmark (N = 580 133; 90% population coverage), Norway (N = 540 890) and Sweden (N = 941 403) and from 2001-2014 in Finland (N = 568 026), we test whether advanced maternal age at birth independently increases the risk of low birthweight (LBW) (<2500 g) and pre-term birth (<37 weeks gestation). We estimated within-family models to reduce confounding by unobserved maternal characteristics shared by siblings using three model specifications: Model 0 examines the bivariate association; Model 1 adjusts for parity and sex; Model 2 for parity, sex and birth year.

RESULTS

The main results (Model 1) show an increased risk in LBW and pre-term delivery with increasing maternal ages. For example, compared with maternal ages of 26-27 years, maternal ages of 38-39 years display a 2.2, 0.9, 2.1 and 2.4 percentage point increase in the risk of LBW in Denmark, Finland, Norway and Sweden, respectively. The same patterns hold for pre-term delivery.

CONCLUSIONS

Advanced maternal age is independently associated with higher risk of poor perinatal health outcomes even after adjusting for all observed and unobserved factors shared between siblings.

Vaginal and oral probiotics effect in the prevention of preterm delivery in patients visiting Kamali Hospital, Karaj, Iran in 2020

INTRODUCTION

The prevalence of preterm labor (PTL) is growing, and annually one in ten babies is born prematurely. Various studies have examined the effect of oral or vaginal probiotics on the prevention of preterm labor, which has yielded contrasting results. This study aimed to compare the impact of vaginal and oral probiotics on the prevention of preterm delivery.

METHODS

This clinical trial was performed among 185 pregnant women with a gestational age greater than or equal to 25 weeks visiting Kamali Hospital, Karaj, Iran in 2020. The participants were divided into three groups; intervention group 1 receiving Oral probiotic pill once a day until 37 weeks of pregnancy, intervention group 2 receiving probiotic vaginal suppository once a day until 37 weeks of pregnancy, and control group not receiving any intervention. Patients were then followed up until the end of pregnancy.

RESULTS

Demographic characteristics and gestational age at the time of intervention were not significantly different among the three groups. Overall, 26.7 % in the control group, 30 % in intervention group 1 %, and 22.5 % in intervention group 2 had deliveries less than 37 weeks. There was no significant difference in the frequency of preterm labor and the duration of pregnancy among the groups (all p > 0.05).

CONCLUSION

Probiotics use does not increase the rate of preterm delivery or reduce the duration of pregnancy, but the rate of preterm delivery was lower in the oral probiotic group. Further clinical studies on the impact of probiotics on PTL can yield valuable results.

To Evaluate the Effect of Increasing Maternal Age on Maternal and Neonatal Outcomes in Pregnancies at Advanced Maternal Age

Introduction

Late pregnancies have been a sensitive issue in the society and medical field for many years. The reason for this development could be the increasing use of reproductive techniques, women empowerment and late conceptions. The increased level of education in women, having more responsibilities at work, giving priority to their professional career could be leading to delay in conception and childbearing. Many studies have investigated the effect of advanced maternal age on fetal outcome suggesting higher risk of poor neonatal outcome. Recent studies have debated these outcomes.[1234].

Aims and Objectives

To evaluate the effect of increasing maternal age on maternal and neonatal outcomes in pregnancies at advanced maternal age.

Material and Methods

The study was conducted on 843 women above the age of 35 years who delivered at Dayanand Medical College and Hospital during 2015-2020. Patients were categorized into 2 groups, Group A comprised of pregnant women aged 35-40 years; group B included pregnant women aged >40 years. Various other parameters including parity, gestation at delivery, whether the pregnancies were spontaneous or conceived through ART (assisted reproductive techniques) and other associated co-morbid conditions were noted. The obstetrical, gynecological, medical, surgical, fetal and neonatal complications were studied in both the groups and the data was analyzed with release 9.4 (SAS Institute Inc, Cary, NC).

Results

Out of 843 patients in our study, 81.4% (n=687) belonged to the age group of 35- 40 years. 18.5% (n=156) belonged to the age group of > 40 years. Patients more than 40 years underwent ART for conception more often as compared to group A. Co-morbid medical conditions including chronic hypertension, thyroid diseases, auto immune disorders and obstetric complications such as abortions, oligohydramnios, GDM, placenta previa, PPH was significantly more common in patients with group B. Cesarean delivery rate was significantly more in group B as compared to group A. Neonatal outcome in terms of NICU admissions and preterm birth at less than 35 weeks gestation was seen more frequently in group B as compared to Group A.

Conclusion

Our study concludes that the decision to delay childbearing should be discouraged owing to increased maternal and fetal morbidity associated with advanced maternal age, the risks being higher with increasing maternal age.

Increasing the Prediction Power of Preterm Labor using Interleukin 6 and Fetal Fibronectin as Alarming Signals in Symptomatic Patients

Background: Giving birth at preterm is considered as a bothering problem to both healthcare systems and pregnant women around the world, causing alarming levels of mortality. To avoid this issue, certain biological markers can be employed for early detection to predict the occurrence of the PTD (PTD) ahead of time for giving better medical care to the pregnant women who at risk of PTD. Objective: The current study was performed to evaluate the power of using interleukin-6 (IL-6) and fetal fibronectin (fFN) present in the cervicovaginal fluid (CVF) as predictors of the symptomatic PTD patients. Patients & Methods: In this study, 91 pregnant hospital attendees (24-34 weeks; 18-45 years old) with suggested PTD symptoms, such as abdominal pain and uterine contraction and with cervical length of less than 25mm, were participated. To detect IL-6 and fFN, vaginal swabs were collected for performing an ELISA test to later follow up with the patients within 48hrs, seven days, and 14 days from the first day of admission to the hospital.  Results: No significant association between PTD with patients age, parity, BMI, and gestational age, but significant association with previous history of PTD. There was significant association between PTD and increase the level of CVF fFN and IL-6 with best cut-off value for CVF fFN is(>45ng/ml) with (95%CI of 0.763-0.918) and accuracy of 85.2% with a sensitivity of 73.1% and specificity of 95.6% which is of high significant value (P≤0.01).While CVF of IL-6 (>231pg/ml) with (95% CI of 0.630- 0.820), with accuracy of 73.3%,  sensitivity of 50% and specificity of 96.9% which was statistically significant finding (P≤0.01).The predictive value of combined fFN and IL-6  in women at risk  of preterm labor was 84.6% with sensitivity 84.6%,specificity 92.3%, positive predictive value (PPV) 81.5%, negative predictive value (PPV) 93.8% and accuracy of 90.1%. Conclusion:  Each of fFN or IL-6 located in the CVF may provide a strong predictor of PTD; however, this prediction capability may provide an even stronger signal of detecting PTD ahead of time if both biomarkers requested at the same time.

Effects of household environmental exposure and ventilation in association with adverse birth outcomes: A prospective cohort study in rural China

Prenatal exposure to outdoor air pollution have been associated with birth outcomes. However, there is limited evidence on the adverse effects of household indoor air pollution worldwide, much less in rural areas of China. This study aimed to explore the associations of household environmental factors (primary cooking fuel, housing renovation, and home ventilation) with four adverse birth outcomes (preterm birth (PTB), small for gestational age (SGA), low birth weight (LBW), and term low birth weight (T-LBW)). We conducted a cohort study involving 10,324 pregnancies in women who delivered a live-born infant from 2015 to 2018 in Guangxi, China. Risk ratios and 95% confidence intervals (CI) were estimated with control for reproductive history, lifestyle, home environmental confounders, and other potential confounders. A total of 5.4% of the infants were PTB, 10.7% were SGA, 5.5% had LBW, and 3.0% had T-LBW. Household-use induction cookers as the primary cooking fuel during pregnancy was associated with SGA (RR = 1.31, 95% CI: 1.07-1.60), LBW (1.41, 1.09-1.82), and T-LBW(1.62, 1.16-2.26), as compared with household-use gas as the primary cooking fuel. Housing renovation within one year before pregnancy was associated with PTB (1.45, 1.06-1.98) and LBW (1.56, 1.17-2.09), while housing renovation during pregnancy was associated with a higher risk of SGA only in moderate home ventilation conditions (3.74, 1.69-8.28). Our findings suggested that household-use induction cookers as the primary cooking fuel increased the risks of SGA, LBW, and T-LBW. In addition, housing renovation within one year before pregnancy increased the risks of PTB and LBW. Proper home ventilation may reduce the effect on the association between housing renovation during pregnancy and SGA.

The role of maternal age on the risk of preterm birth among singletons and multiples: a retrospective cohort study in Lombardy, Norther Italy

Background

All over the world, especially in the developed countries, maternal age at birth is rising. This study aimed to assess the role of maternal age on the occurrence of preterm birth (PTB) in a large birth cohort of Lombardy Region, Northern Italy.

Methods

This population-based study used data from regional healthcare utilization databases of Lombardy to identify women who delivered between 2007 and 2017. PTBs were defined as births before 37 completed weeks of gestation and considered according to the gestational age (two categories: < 32 weeks and 32 to 36 weeks). Six maternal age groups were defined (< 20, 20–24, 25–29, 30–34, 35–39, ≥40 years). Logistic regression models were fitted to estimate the crude and adjusted odds ratio (aOR) and the corresponding 95% confidence interval (CI) for PTB among different maternal age groups. Analyses were separately performed according to type of pregnancy (singletons and multiples). Reference group was the age group with the lowest frequency of PTB.

Results

Overall, 49,759 (6.6%) PTBs were observed, of which 41,807 were singletons and 7952 were multiples. Rates of PTB were lowest in the women aged 25–29 years among singletons and in the 30–34 years old group among multiples. Our results described a U-shaped association between maternal age and risk of PTB. In particular, the risk of a singleton PTB between 32 and 36 weeks was significantly higher for women aged less than 20 years (aOR = 1.16, CI 95%: 1.04–1.30) and more than 40 years (aOR = 1.62 CI 95%: 1.54–1.70). The highest risk of a multiple delivery between 32 and 36 weeks was observed among women aged less than 25 years and more than 40 years (aOR = 1.79, CI 95%: 1.01–3.17, aOR = 1.47, CI 95%: 1.16–1.85 and aOR = 1.36, CI 95%: 1.19–1.55 respectively for < 20, 20–24 and > 40 age categories). PTB before 32 completed weeks occurred more frequently in the same age categories, except that among multiples no association with advanced maternal age emerged.

Conclusion

Our study suggested that, after adjustment for potential confounders, both advance and young maternal age were associated with an increased risk of PTB.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-022-04552-y.

Prescription medication use and baseline health status of women with live-birth deliveries in a national data network

BACKGROUND

The US Food and Drug Administration increasingly uses administrative databases to conduct surveillance of medications used during pregnancy. To assess adverse fetal effects, administrative records must be linked between the mother and infant. The Sentinel Initiative's Mother-Infant Linkage Table provides a large cohort of linked deliveries from national, regional, and public insurance claims in the United States for the US Food and Drug Administration to conduct surveillance.

OBJECTIVE

This study aimed to describe baseline health conditions and prescription medication use during pregnancy in cohorts of women with a live-birth delivery linked and not linked to an infant.

STUDY DESIGN

Live-birth deliveries in women aged 10 to 54 years with at least 391 days of medical and drug coverage before delivery were identified in the Sentinel Mother-Infant Linkage Table from 2000 to 2019. Two cohorts were created for analysis: deliveries linked to infant records (linked deliveries, n=2,320,805) and deliveries unable to be linked to an infant (not-linked deliveries, n=504,785). Baseline health conditions, pregnancy history, healthcare utilization, and pregnancy conditions were defined using International Classification of Diseases, Ninth Revision, and International Classification of Diseases, Tenth Revision, diagnosis and procedure codes. Medication exposure was identified in a 90-day prepregnancy period and in each trimester.

RESULTS

Few notable differences were observed between the linked and not-linked deliveries except for maternal age and preterm birth; the not-linked cohort was 3.4 years younger on average and more likely to have a preterm delivery. At baseline among the linked deliveries, the most common conditions were depression and anxiety (5.2% each), acquired hypothyroidism (5.0%), pain conditions (3.9%), and asthma (2.8%). Among linked deliveries, 6.9% had evidence of gestational diabetes mellitus, 3.9% had gestational hypertension, and 4.5% had preeclampsia or eclampsia. The most commonly used medications during pregnancy in the linked deliveries were antibacterials (41.6%) and antiemetics (21.5%); similar medication use patterns were observed in the not-linked cohort. Age trends were observed for some medication groups; anti-infectives, pain medications, and antiemetics were more common in younger mothers, whereas endocrine medications were more common in older mothers.

CONCLUSION

Similarities between the linked and not-linked cohorts suggested that the ability to link mother and infant records is not influenced by maternal health status. In the linked cohort, the prevalence of specific pregnancy complications and medication use were similar to previously reported national estimates. Some baseline comorbidities, such as obesity and smoking, may be underestimated in the Sentinel Mother-Infant Linkage.

The risk of preterm birth in combinations of socioeconomic position and mental health conditions in different age groups: a Danish nationwide register-based cohort study

Background

Inequality in preterm birth is a world-wide challenge that has proved difficult for maternity care services to meet. Reducing the inequality requires identification of pregnant women at particularly high risk of preterm birth in order to target interventions. Therefore, the aim was to estimate the risk of preterm birth in women with different combinations of socioeconomic position, mental health conditions, and age.

Methods

In this nationwide register-based cohort study, we included all first-time mothers that gave birth to a singleton liveborn infant in Denmark between 2000 and 2016. The absolute and relative risk of preterm birth (< 37 weeks of gestation) was examined in different combinations of educational level (high, intermediate, and low) and mental health conditions (no, minor, and moderate/severe) in three age strata (≤23, 24–30, and ≥ 31 years). We estimated the relative risk using Poisson regression with a robust error variance. As additive interaction can help identify subgroups where limited resources can be of best use, we measured the attributable proportion to assess the risk that is due to interaction of the different exposures.

Results

Of the 415,523 included first-time mothers, 6.3% gave birth prematurely. The risk of preterm birth increased with decreasing educational level and increasing severity of mental health conditions in all age strata, but most in women aged ≥31 years. The highest absolute risk was 12.9% [95% CI: 11.2;14.8%] in women aged ≥31 years with low education and moderate/severe mental health conditions resulting in a relative risk of 2.23 [95% CI: 1.93–2.58] compared to the unexposed reference group in that age strata. We found positive additive interaction between low education and mental health conditions in women aged 24–30 and ≥ 31 years and between age ≥ 31 years and combinations of mental health conditions and educational levels.

Conclusion

The inequality in preterm birth increased with increasing age. To reduce inequality in preterm birth focused attention on women with higher age further combined with lower educational levels and mental health conditions is essential.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-021-04138-0.

Associations between pre-pregnancy psychosocial risk factors and infant outcomes: a population-based cohort study in England

BACKGROUND

Existing studies evaluating the association between maternal risk factors and specific infant outcomes such as birthweight, injury admissions, and mortality have mostly focused on single risk factors. We aimed to identify routinely recorded psychosocial characteristics of pregnant women most at risk of adverse infant outcomes to inform targeting of early intervention.

METHODS

We created a cohort using administrative hospital data (Hospital Episode Statistics) for all births to mothers aged 15-44 years in England, UK, who gave birth on or after April 1, 2010, and who were discharged before or on March 31, 2015. We used generalised linear models to evaluate associations between psychosocial risk factors recorded in hospital records in the 2 years before the 20th week of pregnancy (ie, teenage motherhood, deprivation, pre-pregnancy hospital admissions for mental health or behavioural conditions, and pre-pregnancy hospital admissions for adversity, including drug or alcohol abuse, violence, and self-harm) and infant outcomes (ie, birthweight, unplanned admission for injury, or death from any cause, within 12 months from postnatal discharge).

FINDINGS

Of 2 520 501 births initially assessed, 2 137 103 were eligible and were included in the birth outcome analysis. Among the eligible births, 93 279 (4·4%) were births to teenage mothers (age <20 years), 168 186 (7·9%) were births to previous teenage mothers, 51 312 (2·4%) were births to mothers who had a history of hospital admissions for mental health or behavioural conditions, 58 107 (2·7%) were births to mothers who had a history of hospital admissions for adversity, and 580 631 (27·2%) were births to mothers living in areas of high deprivation. 1 377 706 (64·5%) of births were to mothers with none of the above risk factors. Infants born to mothers with any of these risk factors had poorer outcomes than those born to mothers without these risk factors. Those born to mothers with a history of mental health or behavioural conditions were 124 g lighter (95% CI 114-134 g) than those born to mothers without these conditions. For teenage mothers compared with older mothers, 3·6% (95% CI 3·3-3·9%) more infants had an unplanned admission for injury, and there were 10·2 (95% CI 7·5-12·9) more deaths per 10 000 infants.

INTERPRETATION

Health-care services should respond proactively to pre-pregnancy psychosocial risk factors. Our study demonstrates a need for effective interventions before, during, and after pregnancy to reduce the downstream burden on health services and prevent long-term adverse effects for children.

FUNDING

Wellcome Trust.

Factors Associated With Weight, Length, and BMI Change in Adolescents' Offspring in Their First Year of Life

Background: Young maternal age is associated with negative outcomes at birth and with offspring's growth. In low- and middle-income countries, adolescents' offspring growth little has been studied. Objective: To determine the association of maternal sociodemographic characteristics with weight, length, and BMI change in adolescents' offspring in their first year of life. Methods: This is a one-year follow-up study that included adolescent mothers and their offspring from 2010 to 2017. The infant anthropometric variables were performed at birth, 3, 6, and 12 months. Maternal health, pregnancy, and social variables were evaluated as well as birth outcomes. Crude, percentage, Z score, and percentile changes of weight, length, and BMI were evaluated from birth to 1-year-old. Statistical analyses were adjusted by maternal chronological age, socioeconomic status, breastfeeding duration, the timing of introduction of complementary feeding, among other variables. Results: We examined 186 dyads (mother-infant). The median maternal age was 15.5 years, and the mean pre-pregnancy BMI was 20. The mean gestational age was 39.1 weeks for infants, birth weight was 3,039 g, and length at birth was 49.5-cm. Maternal chronological age, the timing of introduction of complementary feeding, socioeconomic status, and maternal occupation were associated with offspring's weight gain at 12 months. Length gain was associated with exclusive breastfeeding. Socioeconomic status and occupation were associated with offspring's BMI change. When performing adjusted multivariable analyses, weight and length at birth were associated weight and BMI at 12 months. Conclusions: Weight at birth may negatively predict infant's weight and BMI changes at 12 months, while length at birth may positively predict the changes. Maternal chronological age, socioeconomic level, occupation, and the timing of the introduction of complementary feeding were associated with the weight change. Only exclusive breastfeeding was associated with length Z-score change in adolescents' offspring in their first 12-months of life.

Advanced maternal age and risk of adverse perinatal outcome among women with congenital heart disease: A nationwide register-based cohort study

BACKGROUND

Women with maternal congenital heart disease have a higher risk of preterm birth (PTB) and giving birth to a small for gestational age (SGA) infant. Advanced maternal age (≥35 years) likewise increases the risk of PTB and SGA, probably explained by poorer cardiovascular status. It is likely that advanced maternal age is particularly detrimental in women with congenital heart disease.

OBJECTIVES

We aimed to determine whether the pattern of higher risk of PTB and SGA with higher maternal age varied among women with and without congenital heart disease. We hypothesised that the effect of age is higher among women with congenital heart disease.

METHODS

We did a cohort study using Danish nationwide registers. Births from 1997 to 2014 were included. Cox regressions were used to estimate hazard ratios (HRs) for PTB and SGA. Universal and congenital heart disease-specific references were used for comparison.

RESULTS

We included 932 772 births among 548 314 women. HRs of PTB and SGA were 1.55 (95% confidence interval [CI] 1.37, 1.77) and 1.43 (95% CI 1.29, 1.58) in women with congenital heart disease as compared to women without. For both PTB and SGA, HRs were higher for women ≥35 years as compared to women aged 25-29 years. HRs of PTB and SGA were higher among women with congenital heart disease within all strata of maternal age as compared to women without (eg 3.71, 95% CI 1.80, 7.63 vs 1.63, 95% CI 1.56, 1.70) for SGA for women aged 40-44 years). The pattern of higher risk of PTB and SGA with higher maternal age was, however, similar among women with and without congenital heart disease.

CONCLUSIONS

Women with congenital heart disease had a higher risk of PTB and giving birth to an SGA infant at all maternal ages. These two risk factors did not, however, seem to potentiate each other.

Preterm birth, unplanned hospital contact, and mortality in infants born to teenage mothers in five countries: An administrative data cohort study

BACKGROUND

Young maternal age is associated with lower birthweight and higher rates of preterm birth and childhood hospitalisations. Internationally, teen pregnancy rates vary widely, reflecting differences in social, welfare, and health care factors in different cultural contexts.

OBJECTIVES

To determine whether the increased risk of adverse infant outcomes among teenage mothers varies by country, reflecting different national teenage birth rates and country-specific social/welfare policies, in Scotland (higher teenage pregnancy rates), England, New South Wales (NSW; Australia), Ontario (Canada), and Sweden (lower rates).

METHODS

We used administrative hospital data capturing 3 002 749 singleton births surviving to postnatal discharge between 2010 and 2014 (2008-2012 for Sweden). We compared preterm birth (24-36 weeks' gestation), mortality within 12 months of postnatal discharge, unplanned hospital admissions, and emergency department visits within 12 months of postnatal discharge, for infants born to mothers aged 15-19, 20-24, 25-29, and 30-34 years.

RESULTS

Compared to births to women aged 30-34 years, risks of adverse outcomes among teenage mothers were higher in all countries, but the magnitude of effects was not related to country-specific rates of teenage births. Teenage mothers had between 1.2% (95% confidence interval [CI] 0.7, 1.7, Sweden) and 2.0% (95% CI 1.4, 2.5, NSW) more preterm births, and between 9.8 (95% CI 7.2, 12.4, England) and 19.7 (95% CI 8.7, 30.6, Scotland) more deaths per 10 000 infants, compared with mothers aged 30-34. Between 6.4% (95% CI 5.5, 7.4, NSW) and 25.4% (95% CI 24.7, 26.1, Ontario), more infants born to teenage mothers had unplanned hospital contacts compared with those born to mothers aged 30-34.

CONCLUSIONS

Regardless of country, infants born to teenage mothers had universally worse outcomes than those born to older mothers. This excess risk did not vary by national rates of livebirths to teenage mothers. Current mechanisms to support teenage mothers have not eliminated maternal age-related disparities in infant outcomes; further strategies to mitigate excess risk in all countries are needed.

Parental age and child outcomes

This review summarizes the impact of parental age on children's health outcomes beyond the perinatal period. In the last decades, delayed parenthood with both men and women has become a public health issue. For women, in particular, the size of this delay is substantial. For a few medical conditions, older parental age has a pronounced effect on child morbidity. For most other outcomes, a more modest effect is evident. Although these effects might be limited on an individual level, they have a substantial impact at the level of population health.

Family socioeconomic position and abnormal birth weight: evidence from a Chinese birth cohort

BACKGROUND

Birth weight is a strong determinant of infant short- and long-term health outcomes. Family socioeconomic position (SEP) is usually positively associated with birth weight. Whether this association extends to abnormal birth weight or there exists potential mediator is unclear.

METHODS

We analyzed data from 14,984 mother-infant dyads from the Born in Guangzhou Cohort Study. We used multivariable logistic regression to assess the associations of a composite family SEP score quartile with macrosomia and low birth weight (LBW), and examined the potential mediation effect of maternal pre-pregnancy body mass index (BMI) using causal mediation analysis.

RESULTS

The prevalence of macrosomia and LBW was 2.62% (n = 392) and 4.26% (n = 638). Higher family SEP was associated with a higher risk of macrosomia (OR 1.30, 95% CI 0.93-1.82; OR 1.53, 95% CI 1.11-2.11; and OR 1.59, 95% CI 1.15-2.20 for the 2nd, 3rd, and 4th SEP quartile respectively) and a lower risk of LBW (OR 0.69, 95% CI 0.55-0.86; OR 0.76, 95% CI 0.61-0.94; and OR 0.61, 95% CI 0.48-0.77 for the 2nd, 3rd, and 4th SEP quartile respectively), compared to the 1st SEP quartile. We found that pre-pregnancy BMI did not mediate the associations of SEP with macrosomia and LBW.

CONCLUSIONS

Socioeconomic disparities in fetal macrosomia and LBW exist in Southern China. Whether the results can be applied to other populations should be further investigated.

Parental Age and Offspring Childhood Mental Health: A Multi-Cohort, Population-Based Investigation

To examine the contributions of maternal and paternal age on offspring externalizing and internalizing problems, this study analyzed problem behaviors at age 10-12 years from four Dutch population-based cohorts (N = 32,892) by a multiple informant design. Bayesian evidence synthesis was used to combine results across cohorts with 50% of the data analyzed for discovery and 50% for confirmation. There was evidence of a robust negative linear relation between parental age and externalizing problems as reported by parents. In teacher-reports, this relation was largely explained by parental socio-economic status. Parental age had limited to no association with internalizing problems. Thus, in this large population-based study, either a beneficial or no effect of advanced parenthood on child problem behavior was observed.

Changing trends of adverse pregnancy outcomes with maternal age in primipara with singleton birth: A join point analysis of a multicenter historical cohort study in China in 2011-2012

INTRODUCTION

Adverse pregnancy outcomes are related to two opposite maternal factors, youth and aging. However, the change in trend of specific outcomes with childbearing age is unknown. The aim of this study was to investigate the changing trend of various maternal and neonatal outcomes with maternal age from 17 to 44 years.

MATERIAL AND METHODS

Data were extracted from the medical records from 2011-2012 of 39 public hospitals of 14 cities in China. The eligibility criteria were primiparity and singleton birth. Join point regression analysis was used to estimate the percent change per year of age (PCA) to explore the trends of adverse pregnancy outcomes with regard to maternal age and to identify the join point of maternal age when the trend was changed.

RESULTS

A total of 89 171 women were eligible for analysis. There were four categories of trend styles. Continuously increasing trends were linear for placenta previa (PCA, 0.1%), placenta implantation (PCA, 0.09%) and postpartum hemorrhage (PCA, 0.22%), and nonlinear for gestational diabetes mellitus with one join point of 23 years (PCA, 0.17% and 0.71%) and cesarean section with four join points of 25, 28, 31 and 36 years (PCA, 1.39%, 0.34%, 1.51%, 3.49% and 0.94%). Continuously decreasing trends were linear for intrahepatic cholestasis (PCA, -0.02%) and nonlinear for anemia with one join point of 28 years (PCA, -0.49% and -0.04%). The bidirective trends were downward to upward for preterm birth (PCA, -2.93%, -0.36% and 0.38%), hypertension in pregnancy (PCA, -0.09%, 0.47%), low birthweight (PCA 0.51% and 0.38%), low 1-minute Apgar score (PCA, -0.28% and 0.07%), low 5-minute Apgar score at (PCA, -0.10% and 0.06%) and neonatal intensive care unit admission (PCA, -1.92%, -0.07% and 0.12%) with a nadir age of 28 years. The bidirective trend was upward to downward for macrosomia (PCA, 0.39% and -0.11%), with a peak age of 30 years.

CONCLUSIONS

The changes in the trend of specific outcomes were different with maternal age, which means that youth, aging or both could affect the outcomes.

Adolescent pregnancy and linear growth of infants: a birth cohort study in rural Ethiopia

BACKGROUND

Evidences indicate that the risk of linear growth faltering is higher among children born from young mothers. Although such findings have been documented in various studies, they mainly originate from cross-sectional data and demographic and health surveys which are not designed to capture the growth trajectories of the same group of children. This study aimed to assess the association between young maternal age and linear growth of infants using data from a birth cohort study in Ethiopia.

METHODS

A total of 1423 mother-infant pairs, from a birth cohort study in rural Ethiopia were included in this study. They were followed for five time points, with three months interval until the infants were 12 months old. However, the analysis was based on 1378 subjects with at least one additional follow-up measurement to the baseline. A team of data collectors including nurses collected questionnaire based data and anthropometric measurements from the dyads. We fitted linear mixed-effects model with random intercept and random slope to determine associations of young maternal age and linear growth of infants over the follow-up period after adjusting for potential confounders.

RESULTS

Overall, 27.2% of the mothers were adolescents (15-19 years) and the mean ± SD age of the mothers was 20 ± 2 years. Infant Length for Age Z score (LAZ) at birth was negatively associated with maternal age of 15-19 years (β = - 0.24, P = 0.032). However, young maternal age had no significant association with linear growth of the infants over the follow-up time (P = 0.105). Linear growth of infants was associated positively with improved maternal education and iron-folate intake during pregnancy and negatively with infant illness (P < 0.05).

CONCLUSION

Young maternal age had a significant negative association with LAZ score of infants at birth while its association over time was not influential on their linear growth. The fact that wide spread socio economic and environmental inequalities exist among mothers of all ages may have contributed to the non-significant association between young maternal age and linear growth faltering of infants. This leaves an opportunity to develop comprehensive interventions targeting for the infants to attain optimal catch-up growth.

Risky Health Behaviors of Teenage Mothers and Infant Outcomes in the Japan Environment and Children's Study: A Nationwide Cohort Study

STUDY OBJECTIVE

Few studies have investigated the risky health behaviors and psychosocial characteristics of teenage mothers in countries with a low teenage birth rate, like Japan. We examined the differences in maternal prenatal risky health behaviors and psychosocial characteristics, and birth weight of infants between teenage and adult mothers. DESIGN, SETTING, PARTICIPANTS, INTERVENTIONS, AND MAIN OUTCOME MEASURES: We identified 1159 teenage (age younger than 20 years) and 73,547 adult mothers (20-34 years) who participated a nationwide birth cohort study between 2011 and 2014. Behavioral and psychosocial characteristics were ascertained using questionnaires during pregnancy. Birth weight of infants was verified through medical records. Univariate and multivariable logistic regression were used to assess the association of teenage motherhood and birth weight of infants with parity, marital status, household income, maternal education, job status, preconception body mass index, gestational weight gain, psychological distress, and smoking status.

RESULTS

Teenage mothers were significantly more likely to smoke and have psychological distress and less likely to use alcohol than adult mothers (9.9% vs 4.6%, P < .001; 8.9% vs 3.4%, P < .001; 1.3% vs 2.5%, P < .001, respectively). No association was found between teenage motherhood and low birth weight in infants (odds ratio 0.99; 95% confidence interval, 0.73-1.32). Further, no association was found after adjusting for covariates.

CONCLUSION

A substantially greater number of Japanese teenage mothers smoked and experienced severe psychological distress than adult mothers. Our findings will be useful for future research and for developing effective policies and programs for teenage mothers and their children.

Household renovation before and during pregnancy in relation to preterm birth and low birthweight in China

From October 2010 to April 2012, we conducted a cross-sectional study of associations between household environments and childhood health among preschool children in eight Chinese cities. Here, we analyze associations of early household renovation with preterm birth (PTB), low birthweight (LBW), term low birthweight (Term-LBW), and small for gestational age (SGA). Parents responded to questions about household renovation and their children's gestational age and birthweight. In the multivariate logistic regression analyses, household renovation in the year before pregnancy was significantly associated with LBW (sample size: N = 25 813; adjusted odds ratio (OR) with 95% confidence intervals (CIs): 1.23, 1.01-1.50) and Term-LBW (N = 24 823; 1.29, 1.01-1.67). Household renovation during pregnancy was significantly associated with PTB (N = 25 202; 1.28, 1.01-1.69). These significant associations were also found in the two-level (city-child) logistic regression analyses and in the sensitivity analyses among 21 009 children with complete data in all studied variates. Stronger associations were found in certain subgroups. Our findings indicate that household renovation within one year before pregnancy might be a risk factor for LBW and Term-LBW, while household renovation during pregnancy could be a risk factor for PTB.

Preterm birth, low birthweight, and small for gestational age among women with preeclampsia: Does maternal age matter?

OBJECTIVES

To better understand the effects of maternal age on birth outcomes among preeclampsia (PE) patients, we examined the rates of preterm birth, low birthweight, and small for gestational age (SGA) among different age groups and explored whether maternal age was associated with those adverse outcomes.

STUDY DESIGN

This is a multicenter retrospective study. Data from 1128 PE patients, including 580 with early onset PE and 548 with late onset PE, were analyzed.

MAIN OUTCOME MEASURES

Maternal age was categorized into three groups: <25, 25-34, and ≥35 years. The outcome variables were preterm birth (<37 weeks; subgroups: <28 weeks, 28-33 weeks, and 34-36 weeks), low birthweight (<2500 g; subgroups: <1500 g and <1000 g), and SGA. Logistic regression was used to analyze the associations between maternal age groups and outcomes.

RESULTS

In early onset PE, compared with maternal age 25-34 years, maternal age ≥35 years was associated with elevated risk for preterm delivery before 28 weeks, and maternal age <25 years was associated with elevated risk for low birthweight and SGA. When the analysis was restricted to women who underwent cesarean section, elevated risks for preterm birth and/or low birthweight were observed for women younger than 25 years in both early and late onset PE.

CONCLUSIONS

Among women with PE, maternal age <25 years could add risk to preterm birth and/or low birthweight. For women with early onset PE, maternal age ≥35 years is a risk factor for preterm delivery before 28 weeks.

Birth weight, gestational age and late adolescent liver function using twin status as instrumental variable in a Hong Kong Chinese birth cohort: "Children of 1997"

Birth weight (BW) is inversely associated with diabetes and liver function in Mendelian Randomization studies. Observationally, lower BW is usually also associated with poorer liver function. However, these studies could be confounded by socioeconomic position. Here we assessed if BW is associated with liver function in a unique population with little socio-economic patterning of BW, using both instrumental variable and an observational analysis. We used instrumental variable analysis (IVA) to assess the association of BW with liver function (alanine transaminase (ALT), alkaline phosphatase (ALP), bilirubin, and albumin) at ~17 years with twin status as an instrumental variable in the prospective population-representative "Children of 1997" birth cohort (n = 8327). We also conducted an observational analysis adjusted for sex, maternal age, maternal migrant status, smoking and parental socio-economic position. A generalized linear model with gamma family was used for ALT, ALP, and bilirubin because they are not normally distributed. Using IVA, BW was not associated with ALT, ALP or bilirubin, but was possibly negatively associated with albumin (-1.12 g/L, 95% confidence interval (CI) -2.08 to -0.16). Observationally, BW was negatively associated with ALT (-1.23 IU/L, 95% CI -2.16 to -0.30), ALP (-1.72 IU/L, 95% CI -3.43 to -0.01) and higher albumin (-0.23 g/L, 95% CI -0.40 to -0.06). Poor liver function may be a pathway by which the risks of lower BW are actuated. This insight might help identify post-natal targets of intervention to mitigate the adverse health effects of lower birth weight.

Maternal age and offspring developmental vulnerability at age five: A population-based cohort study of Australian children

BACKGROUND

In recent decades, there has been a shift to later childbearing in high-income countries. There is limited large-scale evidence of the relationship between maternal age and child outcomes beyond the perinatal period. The objective of this study is to quantify a child's risk of developmental vulnerability at age five, according to their mother's age at childbirth.

METHODS AND FINDINGS

Linkage of population-level perinatal, hospital, and birth registration datasets to data from the Australian Early Development Census (AEDC) and school enrolments in Australia's most populous state, New South Wales (NSW), enabled us to follow a cohort of 99,530 children from birth to their first year of school in 2009 or 2012. The study outcome was teacher-reported child development on five domains measured by the AEDC, including physical health and well-being, emotional maturity, social competence, language and cognitive skills, and communication skills and general knowledge. Developmental vulnerability was defined as domain scores below the 2009 AEDC 10th percentile cut point. The mean maternal age at childbirth was 29.6 years (standard deviation [SD], 5.7), with 4,382 children (4.4%) born to mothers aged <20 years and 20,026 children (20.1%) born to mothers aged ≥35 years. The proportion vulnerable on ≥1 domains was 21% overall and followed a reverse J-shaped distribution according to maternal age: it was highest in children born to mothers aged ≤15 years, at 40% (95% CI, 32-49), and was lowest in children born to mothers aged between 30 years and ≤35 years, at 17%-18%. For maternal ages 36 years to ≥45 years, the proportion vulnerable on ≥1 domains increased to 17%-24%. Adjustment for sociodemographic characteristics significantly attenuated vulnerability risk in children born to younger mothers, while adjustment for potentially modifiable factors, such as antenatal visits, had little additional impact across all ages. Although the multi-agency linkage yielded a broad range of sociodemographic, perinatal, health, and developmental variables at the child's birth and school entry, the study was necessarily limited to variables available in the source data, which were mostly recorded for administrative purposes.

CONCLUSIONS

Increasing maternal age was associated with a lesser risk of developmental vulnerability for children born to mothers aged 15 years to about 30 years. In contrast, increasing maternal age beyond 35 years was generally associated with increasing vulnerability, broadly equivalent to the risk for children born to mothers in their early twenties, which is highly relevant in the international context of later childbearing. That socioeconomic disadvantage explained approximately half of the increased risk of developmental vulnerability associated with younger motherhood suggests there may be scope to improve population-level child development through policies and programs that support disadvantaged mothers and children.

Age at Menarche and Cardiometabolic Health: A Sibling Analysis in the Scottish Family Health Study

BACKGROUND

Previous studies of age at menarche and cardiometabolic health report conflicting findings, and only a few could account for childhood characteristics. We aimed to estimate the associations of age at menarche with cardiovascular risk factors in unrelated women and within sister groups, under the assumption that within-sibship estimates will be better adjusted for shared genetics and early life environment.

METHODS AND RESULTS

Our study included 7770 women, from 5984 sibships, participating in the GS:SFHS (Generation Scotland: Scottish Family Health Study). We used fixed- and between-effects linear regression to estimate the associations within sister groups and between unrelated individuals, respectively. Within sibships, the mean difference between sisters with early menarche (≤11 years) and sisters with menarche at 12 to 13 years was 1.73 mm Hg (95% confidence interval [CI], -0.41 to 3.86) for systolic blood pressure, 1.26 mm Hg (95% CI, -0.02 to 2.55) for diastolic blood pressure, -0.06 nmol/L (95% CI, -0.11 to -0.02) for high-density lipoprotein, 0.20 nmol/L (95% CI, 0.08-0.32) for non-high-density lipoprotein, -0.34% (95% CI, -1.98 to 1.30) for glucose, 1.60 kg/m² (95% CI, 0.92-2.28) for body mass index, and 2.75 cm (95% CI, 1.06-4.44) for waist circumference. There was weak evidence of associations between later menarche (14-15 or ≥16 years) and lower body mass index, waist circumference, and blood pressure. We found no strong evidence that estimates from within- and between-sibship analyses differed (all P values >0.1). The associations with other cardiovascular risk factors were attenuated after adjustment for adult body mass index.

CONCLUSIONS

Our results suggest that confounding by shared familial characteristics is unlikely to be a major driver of the association between early menarche and adverse cardiometabolic health but do not exclude confounding by individual-level characteristics.

Effect of maternal age on the risk of preterm birth: A large cohort study

BACKGROUND

Maternal age at pregnancy is increasing worldwide as well as preterm birth. However, the association between prematurity and advanced maternal age remains controversial.

OBJECTIVE

To evaluate the impact of maternal age on the occurrence of preterm birth after controlling for multiple known confounders in a large birth cohort.

STUDY DESIGN

Retrospective cohort study using data from the QUARISMA study, a large Canadian randomized controlled trial, which collected data from 184,000 births in 32 hospitals. Inclusion criteria were maternal age over 20 years. Exclusion criteria were multiple pregnancy, fetal malformation and intra-uterine fetal death. Five maternal age categories were defined and compared for maternal characteristics, gestational and obstetric complications, and risk factors for prematurity. Risk factors for preterm birth <37 weeks, either spontaneous or iatrogenic, were evaluated for different age groups using multivariate logistic regression.

RESULTS

165,282 births were included in the study. Chronic hypertension, assisted reproduction techniques, pre-gestational diabetes, invasive procedure in pregnancy, gestational diabetes and placenta praevia were linearly associated with increasing maternal age whereas hypertensive disorders of pregnancy followed a "U" shaped distribution according to maternal age. Crude rates of preterm birth before 37 weeks followed a "U" shaped curve with a nadir at 5.7% for the group of 30-34 years. In multivariate analysis, the adjusted odds ratio (aOR) of prematurity stratified by age group followed a "U" shaped distribution with an aOR of 1.08 (95%CI; 1.01-1.15) for 20-24 years, and 1.20 (95% CI; 1.06-1.36) for 40 years and older. Confounders found to have the greatest impact were placenta praevia, hypertensive complications, and maternal medical history.

CONCLUSION

Even after adjustment for confounders, advanced maternal age (40 years and over) was associated with preterm birth. A maternal age of 30-34 years was associated with the lowest risk of prematurity.

Nulliparous teenagers and preterm birth in California

BACKGROUND

Young maternal age is one of the numerous risk factors for delivery before 37 weeks of gestation, yet the mechanisms are unclear. The purpose of the current study was to investigate the association between teenagers and the risk of preterm birth (PTB) in a large and recent cohort study.

METHODS

We conducted a population-based retrospective cohort study using 2007-2011 California birth certificate records linked with hospital discharge indices and United States census data for nulliparous 13-20 year olds who gave birth to singletons. Maternal age was examined categorically at 1 year intervals. PTB was defined as delivery at <37 weeks of gestation with further distinction between <32 and 32-36 weeks, and between spontaneous and medically indicated deliveries. Adjusted multivariable logistic regression was used to estimate odds ratios (OR) for PTB.

RESULTS

The prevalence of PTB was highest among the youngest (13 year olds, 14.5%) and lowest among the oldest (20 year olds, 6.7%). After adjusting for maternal and paternal race/ethnicity, paternal age, initiation of prenatal care, source of payment, pre-pregnancy body-mass-index (BMI), height, smoking, and poverty; young mothers of ages 13, 14, 15, and 16 years had increased odds for spontaneous PTB at <32 weeks [OR (CI): 3.76 (1.83-7.75), 1.65 (1.10-2.48), 1.55 (1.24-1.93), 1.19 (1.00-1.42), respectively] compared to 20 year olds. All teenagers, excluding 19 year olds, had elevated odds of spontaneous PTB at 32-36 weeks.

CONCLUSIONS

Nulliparous teenagers were at increased risk for spontaneous PTB, especially those 16 years or younger. Medically indicated PTB was not associated with young age.

Is advanced paternal age a health risk for the offspring?

In this article we review the epidemiologic evidence for adverse health effects in offspring of fathers of advanced age. First the evidence regarding fetal survival is addressed, and afterward we review the evidence regarding morbidity in children with older fathers. The adverse conditions most consistently associated with increased paternal age are stillbirths, musculo-skeletal syndromes, cleft palate, acute lymphoblastic leukemia and retinoblastoma, and neurodevelopmental disorders in the autism spectrum and schizophrenia. Finally, we consider the public health impact of the increasing paternal age. We conclude that the adverse health effects in children that might be caused by the present increase in paternal age are severe but quantitatively of minor importance. However, identification of morbidities that are more frequent in offspring of older fathers, after having taken any maternal age effects and other confounding into account, may lead to a better understanding of the pathogenesis behind such conditions.

Advanced maternal age increases the risk of very preterm birth, irrespective of parity: a population-based register study

OBJECTIVE

To investigate whether advanced maternal age is associated with preterm birth, irrespective of parity.

DESIGN

Population-based registry study.

SETTING

Swedish Medical Birth Register.

POPULATION

First, second, and third live singleton births to women aged 20 years or older in Sweden, from 1990 to 2011 (n = 2 009 068).

METHODS

Logistic regression analysis was used in each parity group to estimate risks of very and moderately preterm births to women at 20-24, 25-29, 30-34, 35-39, and 40 years or older, using 25-29 years as the reference group. Odds ratios (ORs) were adjusted for year of birth, education, country of birth, smoking, body mass index, and history of preterm birth. Age-related risks of spontaneous and medically indicated preterm births were also investigated.

MAIN OUTCOME MEASURES

Very preterm (22-31 weeks of gestation) and moderately preterm (32-36 weeks) births.

RESULTS

Risks of very preterm birth increased with maternal age, irrespective of parity: adjusted ORs in first, second, and third births ranged from 1.18 to 1.28 at 30-34 years, from 1.59 to 1.70 at 35-39 years, and from 1.97 to 2.40 at ≥40 years. In moderately preterm births, age-related associations were weaker, but were statistically significant from 35-39 years in all parity groups. Advanced maternal age increased the risks of both spontaneous and medically indicated preterm births.

CONCLUSIONS

Advanced maternal age is associated with an increased risk of preterm birth, irrespective of parity, especially very preterm birth. Women aged 35 years and older, expecting their first, second, or third births, should be regarded as a risk group for very preterm birth.

TWEETABLE ABSTRACT

Women aged 35 years and older should be regarded as a risk group for very preterm birth, irrespective of parity.

At what age does the risk for adverse maternal and infant outcomes increase? Nationwide register-based study on first births in Finland in 2005-2014

INTRODUCTION

It is poorly understood if there are specific ages at which adverse outcomes during pregnancy and childbirth start to increase (threshold-ages). The purpose of this study was to examine at which maternal ages the use of maternity care and the risks for adverse maternal and infant outcomes increase.

MATERIAL AND METHODS

National data from the Finnish Medical Birth Register including all first-time mothers aged 20 years or over with singleton pregnancies in 2005-2014 were analyzed (n = 228 348). Odds ratios for each outcome at different ages were calculated by logistic regression, using women aged 20-24 (n = 56 282) as the reference and adjusting for socioeconomic position and urbanity of residence. The threshold-age was defined as the first significant adjusted odds ratio after which the risk remained significant.

RESULTS

The threshold-ages for use of maternity care varied from 25 years for cesarean section (OR 1.08, 95% CI 1.03-1.14) to 38 years for having 16 or more antenatal visits (1.13, 1.04-1.21). Four threshold-ages were found for maternal health outcomes: 25 years for gestational diabetes (OR 1.15, 1.09-1.23), 27 years for placenta previa (OR 1.75, 1.11-2.75), 33 years for gestational hypertension (1.14, 1.03-1.27), and 38 years for preeclampsia (OR 1.48, 1.12-1.96). The threshold-ages for infant health outcomes varied from 28 years for preterm birth (37 weeks, OR 1.10, 1.02-1.19) to 36 years for perinatal mortality (OR 2.10, 1.44-3.07).

CONCLUSIONS

Different threshold-ages were identified. Most adverse outcomes occurred earlier than the traditional cut-off ages for high risk pregnancy, which have been set at 35 or 40 years.

HIV-exposed children account for more than half of 24-month mortality in Botswana

Background

The contribution of HIV-exposure to childhood mortality in a setting with widespread antiretroviral treatment (ART) availability has not been determined.

Methods

From January 2012 to March 2013, mothers were enrolled within 48 h of delivery at 5 government postpartum wards in Botswana. Participants were followed by phone 1–3 monthly for 24 months. Risk factors for 24-month survival were assessed by Cox proportional hazards modeling.

Results

Three thousand mothers (1499 HIV-infected) and their 3033 children (1515 HIV-exposed) were enrolled. During pregnancy 58 % received three-drug ART, 23 % received zidovudine alone, 11 % received no antiretrovirals (8 % unknown); 2.1 % of children were HIV-infected by 24 months. Vital status at 24 months was known for 3018 (99.5 %) children; 106 (3.5 %) died including 12 (38 %) HIV-infected, 70 (4.7 %) HIV-exposed uninfected, and 24 (1.6 %) HIV-unexposed. Risk factors for mortality were child HIV-infection (aHR 22.6, 95 % CI 10.7, 47.5 %), child HIV-exposure (aHR 2.7, 95 % CI 1.7, 4.5) and maternal death (aHR 8.9, 95 % CI 2.1, 37.1). Replacement feeding predicted mortality when modeled separately from HIV-exposure (aHR 2.3, 95 % CI 1.5, 3.6), but colinearity with HIV-exposure status precluded investigation of its independent effect. Applied at the population level (26 % maternal HIV prevalence), an estimated 52 % of child mortality occurs among HIV-exposed or HIV-infected children.

Conclusions

In a programmatic setting with high maternal HIV prevalence and widespread maternal and child ART availability, HIV-exposed and HIV-infected children still account for most deaths at 24 months. Lack of breastfeeding was a likely contributor to excess mortality among HIV-exposed children.

Socio-economic risk factors for preterm birth in Norway 1999–2009

Aims: Preterm birth is a major cause of perinatal mortality and morbidity and is strongly associated with socio-economic factors. The objective of this study was to examine the associations of maternal education, marital status and ethnicity with preterm birth and to determine the extent to which such associations can be explained by the established risk factors of maternal age, parity and smoking. Methods: This was a register-based cohort study with data from the Medical Birth Registry of Norway 1999–2009 and Statistics Norway. The sample included all singleton spontaneous births in Norway from 1999 to 2009 ( n=494,073). The main outcome measure was preterm birth (gestational age <37 weeks). Results: Low maternal education and single motherhood were associated with preterm birth. After adjustment for the established risk factors, the excess risks were reduced, but remained statistically significant. The relative risk for low education was reduced from 1.50 to 1.36 and for single motherhood from 1.50 to 1.28. Women from Asia had a higher risk of preterm birth than Norwegian-born women (relative risk 1.29) with minor effects of adjustment. Conclusions: Several socio-economic risk factors are associated with preterm birth in Norway. In addition to the established risk factors, prenatal health care should focus on high-risk groups defined by maternal education, marital status and ethnicity.

Impact of family planning programs in reducing high-risk births due to younger and older maternal age, short birth intervals, and high parity

Several studies show that maternal and neonatal/infant mortality risks increase with younger and older maternal age (<18 and >34 years), high parity (birth order >3), and short birth intervals (<24 months). Family planning programs are widely viewed as having contributed to substantial maternal and neonatal mortality decline through contraceptive use--both by reducing unwanted births and by reducing the burden of these high-risk births. However, beyond averting births, the empirical evidence for the role of family planning in reducing high-risk births at population level is limited. We examined data from 205 Demographic and Health Surveys (DHS), conducted between 1985 and 2013, to describe the trends in high-risk births and their association with the pace of progress in modern contraceptive prevalence rate (yearly increase in rate of MCPR) in 57 developing countries. Using Blinder-Oaxaca decomposition technique, we then examine the contributions of family planning program, economic development (GDP per capita), and educational improvement (secondary school completion rate) on the progress of MCPR in order to link the net contribution of family planning program to the reduction of high-risk births mediated through contraceptive use. Countries that had the fastest progress in improving MCPR experienced the greatest declines in high-risk births due to short birth intervals (<24 months), high parity births (birth order >3), and older maternal age (>35 years). Births among younger women <18 years, however, did not decline significantly during this period. The decomposition analysis suggests that 63% of the increase in MCPR was due to family planning program efforts, 21% due to economic development, and 17% due to social advancement through women's education. Improvement in MCPR, predominately due to family planning programs, is a major driver of the decline in the burden of high-risk births due to high parity, shorter birth intervals, and older maternal age in developing countries. The lack of progress in the decline of births in younger women <18 years of age underscores the need for more attention to ensure that quality contraceptive methods are available to adolescent women in order to delay first births. This study substantiates the significance of family planning programming as a major health intervention for preventing high-risk births and associated maternal and child mortality, but it highlights the need for concerted efforts to strengthen service provision for adolescents.

Family structure and use of prenatal care

This cross-sectional study intended to assess the use of prenatal care according to the family structure in a population with free universal access to prenatal care. In 2005-2006, the Portuguese birth cohort was assembled by the recruitment of puerperae at public maternity wards in Porto, Portugal. In the current analysis, 7,211 were included. Data on socio-demographic characteristics, obstetric history, and prenatal care were self-reported. Single mothers were considered as those whose household composition did not include a partner at delivery. Approximately 6% of the puerperae were single mothers. These women were more likely to have an unplanned pregnancy (OR = 6.30; 95%CI: 4.94-8.04), an inadequate prenatal care (OR = 2.30; 95%CI: 1.32-4.02), and to miss the ultrasound and the intake of folic acid supplements during the first trimester of pregnancy (OR = 1.71; 95%CI: 1.30-2.27; and OR = 1.67; 95%CI: 1.32-2.13, respectively). The adequacy and use of prenatal care was less frequent in single mothers. Educational interventions should reinforce the use and early initiation of prenatal care.

Respiratory consequences of late preterm birth

In developed countries most preterm births occur between 34 and 37 weeks' gestation. Deliveries during this 'late preterm' period are increasing and, since even mild prematurity is now recognised to be associated with adverse health outcomes, this presents healthcare challenges. Respiratory problems associated with late preterm birth include neonatal respiratory distress, severe RSV infection and childhood wheezing. Late preterm birth prematurely interrupts in utero lung development and is associated with maternal and early life factors which adversely affect the developing respiratory system. This review considers 1) mechanisms underlying the association between late preterm birth and impaired respiratory development, 2) respiratory morbidity associated with late preterm birth, particularly long-term outcomes, and 3) interventions which might protect respiratory development by addressing risk factors affecting the late preterm population, including maternal smoking, early life growth restriction and vulnerability to viral infection.

Association between maternal age at childbirth and child and adult outcomes in the offspring: a prospective study in five low-income and middle-income countries (COHORTS collaboration)

BACKGROUND

Both young and advanced maternal age is associated with adverse birth and child outcomes. Few studies have examined these associations in low-income and middle-income countries (LMICs) and none have studied adult outcomes in the offspring. We aimed to examine both child and adult outcomes in five LMICs.

METHODS

In this prospective study, we pooled data from COHORTS (Consortium for Health Orientated Research in Transitioning Societies)-a collaboration of five birth cohorts from LMICs (Brazil, Guatemala, India, the Philippines, and South Africa), in which mothers were recruited before or during pregnancy, and the children followed up to adulthood. We examined associations between maternal age and offspring birthweight, gestational age at birth, height-for-age and weight-for-height Z scores in childhood, attained schooling, and adult height, body composition (body-mass index, waist circumference, fat, and lean mass), and cardiometabolic risk factors (blood pressure and fasting plasma glucose concentration), along with binary variables derived from these. Analyses were unadjusted and adjusted for maternal socioeconomic status, height and parity, and breastfeeding duration.

FINDINGS

We obtained data for 22 188 mothers from the five cohorts, enrolment into which took place at various times between 1969 and 1989. Data for maternal age and at least one outcome were available for 19 403 offspring (87%). In unadjusted analyses, younger (≤19 years) and older (≥35 years) maternal age were associated with lower birthweight, gestational age, child nutritional status, and schooling. After adjustment, associations with younger maternal age remained for low birthweight (odds ratio [OR] 1·18 (95% CI 1·02-1·36)], preterm birth (1·26 [1·03-1·53]), 2-year stunting (1·46 [1·25-1·70]), and failure to complete secondary schooling (1·38 [1·18-1·62]) compared with mothers aged 20-24 years. After adjustment, older maternal age remained associated with increased risk of preterm birth (OR 1·33 [95% CI 1·05-1·67]), but children of older mothers had less 2-year stunting (0·64 [0·54-0·77]) and failure to complete secondary schooling (0·59 [0·48-0·71]) than did those with mothers aged 20-24 years. Offspring of both younger and older mothers had higher adult fasting glucose concentrations (roughly 0·05 mmol/L).

INTERPRETATION

Children of young mothers in LMICs are disadvantaged at birth and in childhood nutrition and schooling. Efforts to prevent early childbearing should be strengthened. After adjustment for confounders, children of older mothers have advantages in nutritional status and schooling. Extremes of maternal age could be associated with disturbed offspring glucose metabolism.

FUNDING

Wellcome Trust and the Bill & Melinda Gates Foundation.

The association of maternal age with birthweight and gestational age: a cross-cohort comparison

BACKGROUND

We examined the associations of maternal age with low birthweight (LBW) and preterm birth in four cohorts from a middle- and a high-income country, where the patterning of maternal age by socio-economic position (SEP) is likely to differ.

METHODS

Population-based birth cohort studies were carried out in the city of Pelotas, Brazil in 1982, 1993, and 2004, and in Avon, UK in 1991 [Avon Longitudinal Study of Parents and Children (ALSPAC)]. Adjustment for multiple indicators of SEP were applied.

RESULTS

Low SEP was associated with younger age at childbearing in all cohorts, but the magnitudes of these associations were stronger in ALSPAC. Inverse associations of SEP with LBW and preterm birth were observed in all cohorts. U-shaped associations were observed between maternal age and odds of LBW in all cohorts. After adjustment for SEP, increased odds of LBW for young mothers (<20 years) attenuated to the null but remained or increased for older mothers (≥ 35 years). Very young (<16 years) maternal age was also associated with both outcomes even after full SEP adjustment. SEP adjusted odds ratio of having a LBW infant in women <16 years and ≥ 35 years, compared with 25-29 years, were 1.48 [95% confidence interval (CI) 1.00, 2.20] and 1.66 [95% CI 1.36, 2.02], respectively. The corresponding results for preterm birth were 1.80 [95% CI 1.23, 2.64)] and 1.38 [95% CI 1.15, 1.67], respectively.

CONCLUSION

Confounding by SEP explains much of the excess risk of LBW and preterm among babies born to teenage mothers as a whole, but not for mothers aged <16 or ≥ 35 years. Given that the proportion of women becoming pregnant at <16 years is smaller than for those ≥ 35 years, the population burden is greater for older age.

Early developmental conditioning of later health and disease: physiology or pathophysiology?

Extensive experimental animal studies and epidemiological observations have shown that environmental influences during early development affect the risk of later pathophysiological processes associated with chronic, especially noncommunicable, disease (NCD). This field is recognized as the developmental origins of health and disease (DOHaD). We discuss the extent to which DOHaD represents the result of the physiological processes of developmental plasticity, which may have potential adverse consequences in terms of NCD risk later, or whether it is the manifestation of pathophysiological processes acting in early life but only becoming apparent as disease later. We argue that the evidence suggests the former, through the operation of conditioning processes induced across the normal range of developmental environments, and we summarize current knowledge of the physiological processes involved. The adaptive pathway to later risk accords with current concepts in evolutionary developmental biology, especially those concerning parental effects. Outside the normal range, effects on development can result in nonadaptive processes, and we review their underlying mechanisms and consequences. New concepts concerning the underlying epigenetic and other mechanisms involved in both disruptive and nondisruptive pathways to disease are reviewed, including the evidence for transgenerational passage of risk from both maternal and paternal lines. These concepts have wider implications for understanding the causes and possible prevention of NCDs such as type 2 diabetes and cardiovascular disease, for broader social policy and for the increasing attention paid in public health to the lifecourse approach to NCD prevention.

Maternal non-Mendelian inheritance of a reduced lifespan? A hypothesis

PURPOSE

A negative correlation exists between advanced maternal age and reproduction. Current data suggest that this correlation is due to a decline in oocyte quality with respect to female age. Since a new individual is derived from the fusion of a single sperm and egg, we tested whether the quality of this material could influence the long-term physiological health of offspring, by examining whether a link between parental age and lifespan of offspring exists.

METHODS

We requested a search from the Swedish demographic database POPUM 3 maintained by the University of Umeå, Sweden between years 1700 and 1900. Parameters requested included mothers' and fathers' age at gestation, the lifespan of the children, cause of death of children and the region of birth.

RESULTS

Complete data was obtained for 30,512 children born to 12,725 mothers and fathers. Kaplan-Meier estimators demonstrated a strong relationship between mother's age at gestation and the longevity of offspring. Extrinsic factors such as century of birth also had an effect on the data. The forward stepwise procedure on Cox's model of proportional hazards suggested that most significant intrinsic factors were mother's lifespan and mother's age at gestation.

CONCLUSIONS

These data demonstrate that intrinsic and extrinsic factors influence the lifespan of children. Among intrinsic factors, mother's lifespan and age at gestation had a significant influence on the data. The influence of intrinsic factors remained significant despite a strong extrinsic influence. We suggest that the influence of the mother on the lifespan of offspring is due to extra-genomic factors.