IVF and Preterm Birth




Zhiqin Bu, Jiaxin Zhang, Linli Hu, and Yingpu Sun

Recently, there are more and more infertile couples getting their own babies by assisted reproductive technology (ART). Even though many progress have been made regarding to live birth rate, the safety of this technology is still a concern for both patients and physicians.

Preterm birth (PTB) is defined by the World Health Organization as delivery before 37 completed weeks of gestation.

Several studies have shown that newborns conceived through the ART procedures were associated with an increased incidence of preterm delivery compared to those conceived spontaneously regardless of the type of ART procedure. According to previous studies, several possible factors such as embryo culture medium, in vitro culture to blastocyst stage, as well as embryo cryopreservation, might be related to PTB in couples treating with ART. In 2013, a study reported that extended culture has previously been held responsible for a higher risk of preterm delivery. However, several other reports are not in line with this study. More recently, another large sample retrospective analysis involved 67,147 in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) cycles reporting there was no significant difference in the risk of PTB after blastocyst stage embryo transfer compared with cleavage stage group. Meanwhile, data also showed that singleton pregnancies after transfer of frozen thawed embryos were associated with a lower preterm birth when compared with those after fresh embryo transfers.


What is IVF?

IVF or in vitro fertilisation is a series of procedures to assist you with conception. In many cases it is used when you cannot fall pregnant because of fertility problems or because of an underlying genetic disorder. IVF can also be considered as a treatment in a number of other situations: if you are single and wish to become a parent, if you are in a same sex relationship or for the purpose of fertility preservation.

The IVF process:

During your natural menstrual cycle, multiple follicles start growing. Usually only 1 follicle is destined to ovulate and release an egg, as the rest go through cell death (atresia). During IVF, hormone injections are used to stimulate the ovaries to help multiple follicles to develop and be monitored and result in the multiple eggs being collected. When the developing follicles reach a certain size, indicating their potential of containing a mature egg (eggs ready to be fertilised with sperm), they are retrieved in an ultrasound-guided procedure under light anaesthetic. The eggs collected are placed with the sperm of your partner, or a donor in a culture dish in the laboratory to allow the eggs to hopefully fertilise, and embryos to develop. The embryos are monitored, and development is assessed over a period of time. Three to five days later, if suitable, one is placed into the uterus of the woman or person undergoing treatment in a procedure called an embryo transfer. If there is more than one embryo, the remaining embryo/s can be frozen and used in future treatment known as a frozen embryo transfer (FET).

What are the benefits and risks of IVF?

IVF is a safe procedure and medical complications are rare. As with all medical procedures, there are some possible health effects for both people undergoing treatment and for children born because of ART - Assisted Reproductive Technology.

Physical complications that need treatment in hospital occur in about one in 100 people going through stimulated IVF cycles. Examples include infection and bleeding post egg collection and OHSS - ovarian hyperstimulation syndrome. OHSS occurs as an excessive response to fertility medications taken during treatment to stimulate the ovaries to produce multiple eggs, which can be a potentially serious problem. IVF clinics monitor patients carefully to reduce the risk of OHSS.

Research shows that IVF pregnancies are more likely to result in high blood pressure and diabetes in the mother later in pregnancy. IVF pregnancies are also more likely to deliver prematurely and give birth via caesarean section. About 6% of babies born from IVF have a birth anomaly, compared to about 4% of all other babies born via spontaneous conception. Although, the majority of birth anomalies are minor, most babies born after IVF are healthy and have no short or long-term problems.

There are also individual factors that can increase your risk of pregnancy complications. Speak to your fertility specialist about your own circumstances.


After possibly a long journey with infertility and enduring many challenges along the way, you are finally pregnant. The actual reason for your infertility may be a risk factor for preterm birth, such as advanced maternal age or chronic illness, which needs to be carefully managed. After a physical and emotional journey, the prospect of then possibly having a baby born early may be hard to deal with. Therefore, you should have a comprehensive management plan for your long-anticipated pregnancy. Regular check-ups, close monitoring and careful preparation for the pregnancy and birth is essential and it is important that you inform health professionals of your fertility journey and challenges.

Excitement, and perhaps a sense of relief about finally being pregnant may at times be replaced with nervousness and maybe anxiety. Your baby may have been difficult to conceive and sometimes it may be difficult to relax and enjoy the pregnancy experience as you fear possible complications. Express how you are feeling both physically and emotionally to your doctor, who may suggest talking to a counsellor or psychologist about your mental health. Connecting with others who have conceived using fertility treatments may be helpful and provide some support as well as hearing of other people’s success stories.

Useful Links

Preterm Alliance


COPE – Centre for Perinatal Excellence 


Fertility Society


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].