Assisted Reproductive Technologies (ART), including in-vitro fertilisation (IVF) and intracytoplasmic sperm injection (ICSI), have been revolutionary for individuals and couples facing infertility. Since the first successful IVF birth in 1978, over one million children have been born worldwide through ART. While ART offers hope and possibility, understanding its success rates, associated risks, and outcomes is vital. This guide provides an overview of ART to help educate individuals considering these treatments.
What Are ART Success Rates?
The effectiveness of ART depends on factors such as the reasons for infertility, age, and the definition of success (e.g., a positive pregnancy test versus live birth). On average, ART offers a 1 in 4 to 1 in 3 chance of conception per cycle. For comparison, couples with no history of infertility have about a 1 in 3 to 1 in 4 chance of conceiving naturally during any given ovulation cycle.
Key Factors Influencing Success:
Age
: Younger individuals typically experience higher success rates.
Infertility Causes
: The underlying reasons for infertility can influence outcomes.
Treatment Details
: Factors like embryo quality, hormone levels, and laboratory conditions play a role in success.
Pregnancy Outcomes with ART
The majority of children born through ART are healthy, with over 90% experiencing no major complications. However, as with naturally conceived pregnancies, there are certain risks.
Common Risks in All Pregnancies:
Miscarriage
(1 in 6 pregnancies)
Ectopic pregnancy
(2 in 100 pregnancies)
Premature birth
(1 in 14 babies)
Congenital abnormalities
(4 in 100 babies have a defect)
Stillbirth or neonatal death
(1 in 100 babies)
Cerebral palsy
(1 in 400 babies)
For ART pregnancies, these risks may increase slightly, especially in cases involving multiple pregnancies or certain genetic conditions.
Impact of Twins and Multiple Pregnancies:
Multiple pregnancies (twins, triplets, or more) are considerably more common with ART than with natural conception. Approximately 1 in 5 ART pregnancies result in multiples compared to 1 in 80 for natural conception.
Risks of Multiple Pregnancies:
Higher likelihood of preterm birth and low birth weight.
Increased risk of maternal complications such as pre-eclampsia, gestational diabetes, and haemorrhage.
Greater chance of developmental and health problems in children, including cerebral palsy (13 per 1,000 births for multiples versus 2.3 per 1,000 for singletons).
To minimise risks, many clinics now recommend single embryo transfer (SET) to promote singleton pregnancies whenever possible.
Congenital Abnormalities and Genetic Concerns
The risk of congenital abnormalities increases slightly with ART, from 3 per 100 in naturally conceived children to 4 per 100 with IVF or ICSI (approximately a 30–40% increase). These include structural or genetic abnormalities, though most cases are mild and do not require treatment.
Genetic Disorders and Imprinting Conditions:
ART may increase the risk of rare genetic imprinting disorders, such as Beckwith-Wiedemann and Angelman syndromes. The risk remains very low (from 1 in 14,000 to 1 in 4,000 births).
Male infertility caused by Y chromosome deletions may be inherited by sons conceived via ICSI, potentially affecting their future fertility.
For couples with known genetic risks, Pre-implantation Genetic Diagnosis (PGD) and prenatal testing (such as amniocentesis or chorionic villus sampling) can offer additional insights.
Long-Term Outcomes for ART Children
Physical Health and Birth Weight:
Single babies born through IVF or ICSI are 2–3 times more likely to be:
Premature.
Low birth weight.
Although these differences exist, follow-up studies have shown no significant developmental disparities between ART and naturally conceived children by age five, when accounting for preterm births and multiple pregnancies.
Adult Health:
It is unclear whether ART-conceived individuals face increased health risks in adulthood. Some studies suggest that low birth weight or prematurity (common in both natural and ART pregnancies) may be linked to long-term risks, such as diabetes or heart disease. Current evidence, however, does not show an elevated cancer risk in ART children.
Reducing Risks for ART Pregnancies
Lifestyle Factors:
Parents can take steps to maximise the health of their children by:
Maintaining healthy lifestyles (e.g., avoiding smoking, drugs, and limiting alcohol).
Ensuring the female partner takes folic acid supplements (400–500 micrograms daily) before conception to reduce the risk of neural tube defects.
Minimising Multiple Births:
The chance of multiple births can be reduced by transferring a single embryo during treatment. This significantly decreases the associated risks, including those of preterm labour and developmental conditions.
Final Considerations for ART
ART offers incredible benefits for those struggling with infertility, but the associated risks and challenges should be carefully considered. Many factors, such as the underlying cause of infertility and individual health, can impact outcomes.
Every couple’s situation is unique, and it is essential to discuss the specifics with a fertility specialist. They can provide information tailored to your circumstances and help guide your decisions about treatment options.