Dr Ellie Rayner from The Maternity Collective takes us through some of the medical considerations when planning a second or subsequent baby and how events of a previous pregnancy and labour may impact your pregnancy next time.
How long should I wait before having another baby?
Planning to have another baby is an incredibly personal and individualised decision that will vary from person to person and from family to family, where no answer is truly right or wrong. There are pros and cons of both small and larger age gaps between pregnancies but as well as the practical, social and financial considerations, there are also some medical factors you might want to take into account during your decision making.
Your current health and wellbeing
Pregnancy places huge demands on your body both physically and emotionally so it is important to allow enough time for your body to recover before thinking about conceiving again. The World Health Organisation (WHO) recommends waiting 2-3 years ideally between pregnancies to reduce the chance of complications with both the mothers and the future baby’s health. This optimal inter-pregnancy interval does vary between different groups of women, for example parents who had difficulty trying to conceive previously or older mothers may want to balance the risks of waiting longer against the risks associated with a shorter birth interval.
A shorter pregnancy interval, defined as conception less than 18 months after a previous birth, is associated with an increased chance of having a preterm baby, having a baby with a low birth weight and of experiencing pregnancy loss. These risks are greater if conception was within 11 months of a previous live birth. These statistics don’t apply to women who have lost a baby. In that situation, a shorter gap lowers their chance of preterm birth.
A longer pregnancy interval can be associated with increased risks of blood pressure problems, particularly if the duration is greater than 5 years. Longer intervals could also have implications if you are then an older mother, with your fertility decreasing with increasing age after 35 years and increased risks to you and your baby during pregnancy if you are aged more than 40 years at the time of conception. Taking all of this into account, the optimal pregnancy interval is currently felt to be between 18 and 23 months, whilst acknowledging some mothers may benefit from a shorter pregnancy interval.
It is technically possible to get pregnant within one month of your baby’s birth, so it is important to ensure you are using effective contraception postnatally if you are sexually active and not wanting to conceive straight away.
Type of previous birth
There are some physical recovery considerations that are important to know about that depend on the previous method of birth you’ve had. If you had a previous vaginal birth and have healed well, there is no minimum recommended time before a future pregnancy. However, if you have had a previous Caesarean Section you are recommended to wait ideally 18 months, and if not, at least 12 months, to allow the scar on your uterus to heal and mature as much as possible to reduce your chance of the scar opening up in a future pregnancy (scar dehiscence) which although uncommon, can be serious pregnancy complication.
In all of these situations it is important to balance the risks and benefits based on your individual situation and what might be right for you, might not be the same for someone else. You can make an appointment to talk to your doctor if you would like to discuss the advantages and disadvantages of shorter and longer birth intervals based on your individual circumstances.
How does my previous pregnancy affect my care next time?
At your booking appointment, if you have had a baby before, your midwife will ask in detail about the events of your previous pregnancy and your labour and birth. If you had a previously uncomplicated labour and vaginal birth and you are otherwise healthy, you will be booked for low risk midwifery-led care. In your first pregnancy you’ll have had up to 10 antenatal appointments, whereas in a second or subsequent pregnancy, if your previous pregnancy was uncomplicated, you’ll only have around 7 appointments routinely this time.
Previous High Blood Pressure
If you had a previous complication such as high blood pressure or pre-eclampsia your midwife will recommend starting a low-dose aspirin tablet daily from your first appointment to reduce your chance of this happening again. Depending on how severe the condition was last time, if you required medication or if you had your baby early, will depend on whether you need additional monitoring with appointments or scans during a future pregnancy. Your midwife will often refer you to an Obstetrician to discuss this and make a plan for your pregnancy care.
Previous Gestational Diabetes
If you have previously had pregnancy diabetes (gestational diabetes mellitus (GDM)) or your previous baby weighed more than 4.5kg at birth you will be recommended to have screening for GDM with an Oral Glucose Tolerance Test at least once, but sometimes twice, during your next pregnancy. If you had previous GDM you have an increased chance of developing diabetes in the future, so it is worth asking your GP to check for this before you conceive to ensure you can get any treatment you need before pregnancy.
Previous Obstetric Cholestasis
Obstetric cholestasis is a pregnancy related liver disorder that can cause a build-up of bile acids in your blood. It is an uncommon condition affecting less than 1% of women, however if you were diagnosed with obstetric cholestasis in a previous pregnancy there is a high chance, between 50-90%, that you will develop the condition again so your midwife will ask you to observe for the symptoms and will arrange testing promptly if they are worried you have developed the condition again.
How does my previous birth affect a future pregnancy?
If you have had a baby before, your midwife will discuss your options for labour and birth this time, including your options for where to give birth based on the previous type of birth you had, and if you had any complications.
Previous spontaneous vaginal birth
If you had a previous spontaneous vaginal birth, your labour is likely to be shorter a subsequent time. For first-time mothers, the average time it takes to dilate to fully dilated (around 10cm) is 8 hours whereas for women who have had a baby vaginally before it is likely to be around 5 hours. Similarly, the second stage of labour, the pushing phase which is from being fully dilated to the birth of your baby, is also likely to be less than 2 hours, compared to less than 3 hours in a first labour.
Previous assisted vaginal birth
If you had a previous assisted vaginal birth with forceps or a ventouse, many women worry that this might happen again. The good news is, that the majority of women, up to 90% or 9 out of 10 women who had a previous assisted vaginal birth will have a spontaneous birth in a subsequent pregnancy without needing assistance.
Previous Caesarean Section
If you had a previous Caesarean Section, you will be referred to the Antenatal clinic during a future pregnancy to discuss your option for birth this time. You have two options, firstly, aiming for a Vagina Birth After Caesarean (VBAC) or secondly choosing to have an Elective Repeat Caesarean Section (ERCS). If you are fit and healthy, both VBAC or an ERCS are safe choices. In general, if you have had 1 previous Caesarean Section and the operation was uncomplicated, you should be offered a VBAC and advised that 75% of women, or 3 out of 4, who go into labour spontaneously will have a successful vaginal birth. VBAC labour carries slightly higher risks for you and your baby compared to if you hadn’t had a Caesarean Section before, therefore you will be advised to birth at a Consultant-led Unit where there is access to continuous foetal monitoring and where there are facilities to perform an immediate Caesarean Section if needed. Your midwife or Obstetrician will discuss the pros and cons of each of these options to you in full taking your previous pregnancy and medical history into account.
Previous Vaginal Tear
Having a vaginal tear during childbirth is extremely common in a first-time mother, with 9 out of 10 having a graze, tear or episiotomy. Fortunately, the number is much lower in women who have had a vaginal birth before. Many women worry about a deeper tear, called a third or a fourth-degree tear that involves the anal sphincters and back passage. The chance of this happening during a first labour is approximately 6% or 6 in every 100 women, however if you have had a vaginal birth before this chance is reduced to only 2% or 2 in every 100 women.
If you have had a previous 3rd or 4th degree tear you will be referred to an Obstetrician in a future pregnancy to discuss your options for birth. Depending on the extent and type of the tear (3a/3b/3c/4th), your recovery, how many children you are planning and whether you are symptomatic or have any ongoing problems, they will discuss the risks and benefits of either planning a vaginal birth or choosing an Elective Caesarean Section. In general, if it was one of the more minor 3rd degree tears, you healed and recovered well and have no ongoing symptoms you will be recommended to have a vaginal birth. Your chance of a repeat 3rd or 4th degree tear is the same as a first-time mother of around 5-7% and they will discuss ways to reduce the chance of this happening again with you.
I think I’m ready for another baby – what should I do?
Women who are healthier at conception have a better chance of becoming pregnant quickly, having a safe and healthy pregnancy and labour and giving birth to a healthy baby. Both you and your partner should try and make sure your lifestyle is as healthy as possible before trying to conceive if you are planning a pregnancy.
Stopping smoking, reducing alcohol intake, having a healthy diet and exercising regularly are all important aspects in improving fertility and pregnancy outcomes.
If you have made the decision to start trying to conceive, make an appointment with your GP to discuss your health and wellbeing and to ensure you receive any specialist advice personalised to you. This is especially important if you have any medical problems or are taking any medication to ensure it is safe for pregnancy.
If you would like any more information on planning a future pregnancy the NHS website ‘Planning another pregnancy’ has lots of detailed advice.
About the Author
Dr Ellie Rayner, Obstetrician and Gynaecologist, Antenatal and Hypnobirthing Teacher and founder of The Maternity Collective.
Dr Ellie Rayner is a practicing Obstetrician and Gynaecologist and founder of The Maternity Collective. She is the only Obstetrician to offer private and group, expert-led Antenatal and Hypnobirthing Classes both Online and face-to-face. She is passionate about providing parent-centred, evidence-based care for all pregnancies and supports all methods of birth. Follow Dr Ellie Rayner @maternitymedic for the latest evidence-based information on pregnancy, birth and women’s health issues.
The Maternity Collective provide comprehensive online antenatal and birth preparation courses led by a team of NHS expert healthcare professionals, including a Community Midwife, Obstetrician, Internationally Board-Certified Lactation Consultant (IBCLC) and Newborn Sleep and Behaviour Expert. They offer a complete 7 hour online antenatal and birth preparation course that can undertaken from the safety of your own home, at your own pace with videos to re-watch as many times as needed. More information is available at https://www.thematernitycollective.co.uk/