Mother’s Age and its Effect on Pregnancy    


Teenage Mothers 


Infants born to teenage mothers are more likely to be preterm, have low birthweight and be small for gestational age. A recent Australian report on teenage mothers documented the rates of preterm birth and low birthweight among the babies of teenage mothers to be 11% and 8.9%, respectively; these figures were 9.9% and 7.6%, respectively, for mothers aged 20–24 years. These outcomes are worsened if the teenage mother is from a low socioeconomic or Aboriginal or Torres Strait Islander background. Similarly, stillbirth and neonatal death rates have also been found to be higher in babies born to Australian mothers aged <20 years compared with mothers aged 20–24 years: 13.9 in comparison to 7.8 stillbirths per 1000 births, and 4.3 in comparison to 2.9 neonatal deaths per 1000 live births.  

Pregnant teenagers need to be educated about the importance of fetal movements and what to do if there is a change in the pattern of fetal movements. It is important that healthcare practitioners understand these risks and monitor fetal development and maternal health more carefully in the third trimester, with consideration of extra assessments of fetal wellbeing including ultrasonography at 36 weeks’ gestation. 


In 2020, women who gave birth aged under 20 accounted for 1.8% (5,216) of all mothers. The number of teenage mothers giving birth has more than halved since 2010 (11,370) and the proportion has fallen from 3.8%. 

In 2020, most babies born to mothers aged under 20 were born at term and had a normal birthweight (both 89%). The majority of babies had a hospital stay of 3 days or less (80%). 

Around 1 in 4 babies born to mothers aged under 20 required active resuscitation or admission to SCN/NICU (23% and 25%, respectively). 

Some women who become pregnant under the age of 20 it can be a positive and maturing experience. For many young people, becoming a parent can have a transformative impact, particularly with changing unhealthy behaviours and relationships but some do not have this positive experience. Here are some outcomes that have been noted from recent research.   

Teenage Mothers: 

  • Are more likely to have a spontaneous labour and less likely to have a caesarean section 
  • Less likely to have gestational diabetes. 
  • Who give birth under the age of 20 are also a vulnerable group, who may experience lower education and employment problems. This may increase the risk of socioeconomic problems for both child and mother. Children of vulnerable young parents are also at risk of becoming teenage parents themselves. 
  • Teenage motherhood has several poorer health and wellbeing outcomes for both mother and baby. In the short-term, babies born to teenage mothers are at greater risk of being born pre-term, with a low birthweight, stillbirth and neonatal.  
  • Children of teenage mothers may go on to have behavioural, emotional and cognitive disadvantages. Depression is more prevalent and can have a long-lasting effect on mental health. 

Things to Consider for Teenage Girls, Pregnancy and Care 

  • Seeing your GP 
  • Look for teen specific Ante Natal Care & Birth Classes 
  • Staying Healthy is motiving for the health of your unborn child 
  • Eating healthy and accepting the change in your body stay active too.


Being a teenager and finding out you are expecting a baby, especially if the pregnancy is unintended and not wanted, can put enormous stress on you and your family. However, there is support available to help you to make the wisest choice for you at this time. 

Finding out you are pregnant — or that you will become a teenager father — can bring up many different emotions. You might feel confused and scared, or happy and excited. All these feelings are normal and okay. Your feelings will probably also change while you are thinking about your options. 

Getting support from your family, friends and services in the community can help you cope. 

Useful Links 

Brave Foundation – this charity equips expecting and parenting teens with resources, referral and education opportunities to facilitate happy, healthy and skilled families over time. 


The Raising Children Website has really good information for parents of the pregnant teenager as well as information for the young parents. 

Advanced maternal age Mothers 


This report was written by Alana Cameron and Alison Childs of the Australian Institute of Health and Welfare. The authors gratefully acknowledge the contributions of the following AIHW staff: Bernice Cropper, Louise Gates, Fadwa Al-Yaman, Michael Humphrey, Jeremy Oats, Jacqueline Rek, Kathryn Sedgewick, Denae Cotter, Louise Catanzariti, Maddy Elkington, Rebecca Dickson and Michelle Welch. 

Women are increasingly having children later in life, and the majority of older mothers will have uncomplicated pregnancies and healthy babies (AIHW 2021; Royal Hospital for Women 2016). In Australia, more than 60% of women were aged 30 or over when they gave birth in 2019 compared with 54% in 2010 (AIHW 2021). In addition, during 2019 more than half (51%) of women giving birth for the first time were aged 30 or over, compared with 42% in 2010 (AIHW 2021).  

There are advantages to giving birth later in life. Women who give birth at older ages are more likely to be socioeconomically advantaged, seem happier after having their child, are more resilient and report lower levels of anxiety and depression during pregnancy than younger mothers (McMahon et al. 2011; Mills & Lavender 2011; Myrskylä et al. 2017). Increasing maternal age has also been associated with better social, emotional and cognitive outcomes for children (Carslake et al. 2017; Goisis et al. 2017; Myrskylä et al. 2017; Sutcliffe et al. 2012; Tearne et al. 2014). 

However, women who give birth later in life are more at risk of complications during pregnancy and birth. This includes increased risk of gestational diabetes, preterm birth, low birthweight and babies that are small or large for gestational age (DoH 2021; Jolly et al. 2000; Kenny et al. 2013; RCOG 2013). Additionally, the incidence of stillbirth at term, while generally low, is higher in older mothers (RCOG, 2013). This has been reported as increasing for women aged over 40 (AIHW 2020a; RCOG 2013). While women in Australia generally conceive without additional intervention, older mothers are more likely to use assisted reproductive technology (ART) to become pregnant. ART has been associated with increased risk of complications including gestational hypertension, pre-eclampsia, congenital anomalies, preterm birth and stillbirth (Howell & Blott 2021). 


What is advanced maternal age? 

Advanced maternal age (AMA) is the term doctors and midwives use to describe a woman who’ll be 35 years of age or older when she gives birth to her baby. 

The term ‘advanced’ might sound a little excessive and 35 is not ‘old’ by life standards. However, from a biological point of view, age is important for a woman – no matter how young you look or feel! 

What are the risks of an advanced maternal age pregnancy? 

While most women over the age of 35 years will still have a healthy pregnancy and baby, virtually all pregnancy risks and complications increase as the age of the woman increases. 

These include: 

  • difficulties conceiving and increased need for fertility advice/treatment 
  • miscarriage in early pregnancy 
  • chromosome or other abnormalities with the baby
  • diabetes – either before pregnancy or developed during pregnancy (gestational diabetes) 
  • high blood pressure – either before pregnancy or developed during pregnancy (also known as pre-eclampsia) 
  • a small or ‘growth restricted’ baby, who may require more intensive monitoring during pregnancy and/or premature delivery 
  • abnormal position of the placenta – which may affect the growth of your baby, cause bleeding problems in pregnancy, and require a caesarean birth 
  • premature birth 
  • stillbirth 
  • your baby not being head down at the end of pregnancy, which may lead to a more complicated vaginal birth or require a caesarean birth 
  • induction of labour 
  • caesarean birth.


In some respects, age is an asset, not a liability. Older Mum’s are much more emotionally ready to be a parent and they have more life experience—they're more likely to honour pregnancy as the sacred experience it is. Regardless of age, there is one thing that will improve the pregnancy outcome is if woman maintains at a healthy weight, takes a prenatal vitamin with folic acid, manages medical conditions, doesn't smoke, and keeps vaccinations up to date, has a better chance of conceiving a healthy baby, and having a healthy pregnancy. Mum’s over 35, there are a few benefits like financial security, and when it's your choice to get pregnant you are much more in control of the process and more prepared to become a parent some parents have said.  

Useful Links  

Pregnancy, Birth and Baby 

COPE – Centre for Perinatal Excellence 

Panda - Perinatal Mental Health




Confirmation Content

Disclaimer: This publication by Miracle Babies Foundation is intended solely for general education and assistance and it is it is not medical advice or a healthcare recommendation. It should not be used for the purpose of medical diagnosis or treatment for any individual condition. This publication has been developed by our Parent Advisory Team (all who are parents of premature and sick babies) and has been reviewed and approved by a Clinical Advisory Team. This publication is not a substitute for professional medical advice. Miracle Babies Foundation recommends that professional medical advice and services be sought out from a qualified healthcare provider familiar with your personal circumstances.To the extent permitted by law, Miracle Babies Foundation excludes and disclaims any liability of any kind (directly or indirectly arising) to any reader of this publication who acts or does not act in reliance wholly or partly on the content of this general publication. If you would like to provide any feedback on the information please email [email protected].