New Evidence Links Both Adolescent and Advanced Maternal Age to Increased Perinatal Complications

Are all maternal ages created equal when it comes to perinatal risk? Clinicians are increasingly faced with pregnancies at both the youngest and oldest ends of the reproductive spectrum. A recent large-scale cohort study published in BMC Pregnancy and Childbirth offers robust new evidence that both adolescent (<19 years) and advanced maternal age (>35 years) are independently linked to a higher risk of adverse obstetric and neonatal outcomes—even after adjusting for key confounders.

Study Design: Comparing Three Age Groups

This retrospective cohort study analyzed 19,728 mother-infant pairs from a tertiary-care hospital over five years. Mothers were divided into three groups: adolescents (<19 years), young adults (19–35 years), and older adults (>35 years). Researchers collected thorough demographic, clinical, and outcome data, and adjusted for confounders such as parity, socioeconomic status, prenatal care adequacy, and comorbidities using multivariable logistic regression.

Key Findings: A U-Shaped Risk Curve

The data revealed a U-shaped curve: both adolescent and older mothers had higher odds of complications compared to the young adult reference group.

Older mothers faced notably increased risks of preeclampsia (adjusted odds ratio [aOR] 3.15), cesarean delivery (aOR 1.89), and preterm birth (aOR 2.94).

Adolescent mothers had lower cesarean rates but were more likely to deliver infants with low birth weight (aOR 1.72) and preterm birth (aOR 1.48).

Both groups saw increased neonatal intensive care unit (NICU) admissions.

Underlying Mechanisms: More Than Just Biology

The study used the Biopsychosocial Model to interpret risk factors. For adolescents, increased risks were partly explained by socioeconomic disadvantage (such as public insurance, lower education, and inadequate prenatal care), but a significant portion persisted after adjustment—suggesting both biological and unmeasured psychosocial influences.

For older mothers, the excess risk was primarily driven by medical comorbidities and age-related biological changes, such as chronic hypertension, diabetes, and use of assisted reproductive technology. Importantly, the risk remained even after adjusting for these factors.

Clinical Implications: Tailored Interventions Needed

These findings underscore the importance of age-specific strategies in prenatal care:

For adolescents: Early, comprehensive prenatal care and targeted social support may mitigate some risks.

For older mothers: Vigilant management of comorbid conditions and close monitoring for hypertensive and metabolic complications are essential.

Why This Matters

Understanding the complex interplay of age, biology, and social determinants allows clinicians to better stratify risk, counsel patients, and allocate resources to those most vulnerable. The evidence reinforces that both ends of the age spectrum deserve nuanced, proactive care to improve outcomes for mothers and babies alike.

Conclusion

Both adolescent and advanced maternal age independently increase the risk of adverse perinatal outcomes—even after accounting for socioeconomic and medical confounders. A personalized, multidisciplinary approach is critical to optimizing pregnancy outcomes across the maternal age spectrum.

Key Points

Both adolescents and women over 35 have higher risks for adverse pregnancy and neonatal outcomes compared to women aged 19–35.

Socioeconomic disadvantage explains much, but not all, of the increased risk in adolescent mothers.

Advanced maternal age remains a strong risk factor, primarily due to medical comorbidities and biological changes.

Age-tailored prenatal care strategies—social support for adolescents, comorbidity management for older mothers—are needed.

Proactive risk assessment and personalized care can improve outcomes at both ends of the maternal age range.

Citation:

Movahedinia S., Soltaninejad N., Nikpour N. et al. Maternal age and perinatal morbidity: a comparative cohort study including advanced maternal age and adolescent pregnancy. BMC Pregnancy and Childbirth. 2026; [in press]. https://doi.org/10.1186/s12884-026-09586-0