Short interpregnancy interval can lead to adverse pregnancy outcomes: A meta-analysis

Effects of short inter-pregnancy/birth interval on adverse perinatal outcomes in Asia-Pacific region: A systematic review and meta-analysis

BACKGROUND

Short inter-pregnancy or birth interval is associated with an increased risk of adverse perinatal outcomes. However, some emerging evidence questions this association and there are also inconsistencies among the existing findings. This study aimed to systematically review the evidence regarding the effect of short inter-pregnancy or birth intervals on adverse perinatal outcomes in the Asia-Pacific region.

METHODS

A comprehensive search of five databases was conducted targeting studies published between 2000 to 2023. Studies that reported on short inter-pregnancy or birth interval and examined adverse perinatal outcomes, such as low birthweight (LBW) preterm birth (PTB), small for gestational age (SGA), and neonatal mortality were included and appraised for methodological quality using the Joanna Briggs Institute critical appraisal tools. Three reviewers independently screened the studies and performed data extraction. Narrative synthesis and meta-analyses were conducted to summarise the key findings.

RESULTS

A total of 41 studies that fulfilled the inclusion criteria were included. A short-interpregnancy interval was associated with an increased risk of low birthweight (odds ratio [OR] = 1.65; 95%CI:1.39, 1.95), preterm birth (OR = 1.50; 95%CI: 1.35, 1.66), and small for gestational age (OR = 1.24; 95%CI:1.09, 1.41). We also found elevated odds of early neonatal mortality (OR = 1.91; 95%CI: 1.11, 3.29) and neonatal mortality (OR = 1.78; 95%CI: 1.25, 2.55) among women with short birth intervals.

CONCLUSION

This review indicates that both short inter-pregnancy and birth interval increased the risk of adverse perinatal outcomes. This underscores the importance of advocating for and implementing strategies to promote optimal pregnancy and birth spacing to reduce the occurrence of adverse perinatal outcomes. Reproductive health policies and programs need to be further strengthened and promote access to comprehensive family planning services and increase awareness about the importance of optimal pregnancy and birth spacing.

Associations between the time interval from myomectomy to subsequent pregnancy and the obstetric outcomes: A population-based cohort study

OBJECTIVE

To investigate the associations between time interval from myomectomy to pregnancy (TIMP) and subsequent pregnancy and obstetric complications, and to explore whether these associations vary according to maternal age at birth.

METHODS

A retrospective population-based cohort study was conducted from 2008 to 2017. Data were extracted from the National Health Insurance Research Database and the Taiwan Maternal and Child Health Database, comprising 2024 379 births from 1 391 856 pregnancies. Eligible cases were identified using diagnostic and procedure codes; 4006 first singleton births in 4006 women after their first laparotomic myomectomy were identified. We estimated the risks of pregnancy and obstetric outcomes according to TIMP (<6, 6-11, and ≥12 months). Subgroup analysis was performed by further dividing according to maternal age at birth (18-34 vs ≥35 years old).

RESULTS

We observed higher risks of gestational hypertensive disorders (adjusted odds ratio [aOR] 1.97, 95% confidence interval [CI] 1.22-3.18, P = 0.005) and neonatal death (aOR 4.59, 95% CI 1.49-14.18, P = 0.008) for TIMP of <6 months versus TIMP of 6-11 months. Likewise, a TIMP ≥12 months was associated with increased risks of gestational hypertensive disorders (aOR 1.72, 95% CI 1.14-2.58, P = 0.010), and neonatal death (aOR 3.27, 95% CI 1.16-9.24, P = 0.025) versus a TIMP of 6-11 months. In subgroup analysis, women over 35 years old still had higher risks of gestational hypertensive disorders when TIMP was <6 months (aOR 2.26, 95% CI 1.17-4.37, P = 0.015) or ≥12 months (aOR 2.04, 95% CI 1.17-3.54, P = 0.012), and a higher risk of neonatal death when TIMP was <6 months (aOR 4.05, 95% CI 1.06-15.53, P = 0.041); whereas women aged 18-34 years old did not.

CONCLUSIONS

This study suggests that a TIMP between 6 and 11 months is associated with lower risks of gestational hypertensive disorders and neonatal death compared with a TIMP <6 months or ≥12 months, especially for women over 35 years old.

FIGO Preconception Checklist: Preconception care for mother and baby

The preconception period is a unique and opportunistic time in a woman's life when she is motivated to adopt healthy behaviors that will benefit her and her child, making this time period a critical "window of opportunity" to improve short- and long-term health. Improving preconception health can ultimately improve both fetal and maternal outcomes. Promoting health before conception has several beneficial effects, including an increase in seeking antenatal care and a reduction in neonatal mortality. Preconception health is a broad concept that encompasses the management of chronic diseases, including optimal nutrition, adequate consumption of folic acid, control of body weight, adoption of healthy lifestyles, and receipt of appropriate vaccinations. Use of the FIGO Preconception Checklist, which includes the key elements of optimal preconception care, will empower women and their healthcare providers to better prepare women and their families for pregnancy.

Fear of childbirth prolongs interpregnancy interval: A nationwide register-based quantile logistic regression analysis

Introduction

It is not well studied how fear of childbirth (FOC) influences the interpregnancy interval (IPI). Thus, we aimed to analyze the association between FOC and the length of the IPI.

Methods

All women having their first and second pregnancies during the study period (2004-2018) were gathered from the Finnish Medical Birth Register. A logistic regression model was used to assess the association between the FOC and subsequent length of the IPI. The length of the IPI was assessed separately for women with FOC in the first pregnancy, and for women who developed the FOC in the second pregnancy. IPIs with a length in the lower quartal were considered short IPIs, and length in the upper quartal as long IPIs. Adjusted odds ratios (aOR) with 95% CIs were compared between the groups.

Results

A total of 52 709 women with short IPI (<1.05 years), 105 604 women with normal IPI, and 52 889 women with long IPI (>2.57 years) were included. A total of 3606 women had FOC in the first pregnancy, and a total of 11 473 had their first FOC diagnosis in the second pregnancy. Women with FOC in the first pregnancy had lower odds for short IPI (aOR 0.88, CI 0.81-0.95) and higher odds for long IPI (aOR 1.30, CI 1.21-1.40). Women with the first FOC diagnosis in the second pregnancy had higher odds for long IPI (aOR 1.68, CI 1.61-1.75), When only vaginal deliveries in the first pregnancy were included, women with FOC in the second pregnancy had lower odds for long IPI (aOR 0.71, CI 0.66-0.75) and higher odds for long IPI (aOR 1.52, CI 1.41-1.62), when only cesarean section was included.

Conclusion

The main finding of this study was that women with FOC had notably higher odds for long IPI. The etiologic and background factors behind FOC should be better recognized and prevented, and FOC should not only be considered as a complicating factor for pregnancy and delivery but also a factor that strongly affects the desire of women to get pregnant again.

Maternal care in wild toque macaques (Macaca sinica) involves prolonged lactation and interbirth intervals as adaptations to reduce maternal depletion and infant mortality in harsh environments

Weaning age in primates has been challenging to measure and new methods, involving molecular biomarkers in feces, tissue, or teeth have contributed to a solution. Here, we used a direct approach by briefly anesthetizing 442 female toque macaques (Macaca sinica) of Sri Lanka (over a 17-year period) and manually testing their mammary tissue for the presence or absence of milk. Milk tests were related to known offspring ages and maternal care behaviors and indicated that older infants suckled milk well past the weaning age of 7 months that is often reported for food-provisioned primates. Mothers strongly rejected their infants' nursing attempts in two phases, the first at 7 months as an honest signal "giving notice" promoting a shift to greater independence from milk to solid food, and when "shutting down" at final weaning after 12-18 months. The shift to supplementary lactation coincided also with the cessation of mothers carrying their infants and a resumption of cycling. All infants up to 7.2 months suckled milk, 91% of them did up to 18 months, this continued for 42% of infants beyond 18 months, and normally none received milk after 22 months. Lactation extended into 2.2% of cycling and 10.7% of pregnant females (up to 50% of gestation). The interbirth interval was prolonged by factors predicted to draw on female metabolic energy reserves and included the duration of lactation, growth among primiparas, and dietary limitations. The last also increased menarche. Females offset the metabolic costs of lactation with increased foraging and catabolism, but infants died when lactation costs seemingly compromised maternal condition. The prolonged lactation and slowed reproduction are considered adaptations to promote infant survival and growth in an environment where the natural food supply limits population growth and competition for food and water impacts the mortality of the youngest the most.

Very Early-Life Risk Factors for Developing Dementia: Evidence From Full Population Registers

OBJECTIVES

Very early-life conditions are recognized as critical for healthy brain development. This study assesses early-life risk factors for developing dementia. In the absence of historical medical birth records, we leverage an alternative full population approach using demographic characteristics obtained from administrative data to derive proxy indicators for birth complications and unfavorable birth outcomes. We use proxy variables to investigate the impact of early-life risk factors on dementia risk.

METHODS

We use administrative individual-level data for full cohorts born 1932-1950 in Sweden with multigenerational linkages. Records on hospitalization and mortality are used to identify dementia cases. We derive 3 birth risk factors based on demographic characteristics: advanced maternal age, narrow sibling spacing, and twin births, and apply survival analysis to evaluate long-term effects on dementia risk. We control for confounding using multiple indicators for socio-economic status (SES), including parental surnames, and by implementing a sibling design. As comparison exposure, we add low education from the 1970 Census.

RESULTS

The presence of at least 1 birth risk factor increases dementia risk (HR = 1.059; 95% CI: 1.034, 1.085). The occurrence of twin births poses a particularly heightened risk (HR = 1.166; 95% CI: 1.084, 1.255).

DISCUSSION

Improvements to the very early-life environment hold significant potential to mitigate dementia risk. A comparison to the influence of low education on dementia (the largest known modifiable risk factor) suggests that demographic birth characteristics are of relevant effect sizes. Our findings underscore the relevance of providing assistance for births experiencing complications and adverse health outcomes to reduce dementia cases.