Ovulation induction and subfertile untreated conception groups offer improved options for interpreting risks...

Area of Science:

• Reproductive Medicine
• Maternal-Fetal Medicine
• Public Health

Background:

• Assisted reproductive technology (ART) is increasingly used for infertility.
• Understanding health outcomes in ART-conceived births requires appropriate comparison groups.
• Previous studies often used fertile naturally conceived births as the sole comparator, potentially obscuring ART-specific risks.

Purpose of the Study:

• To identify and characterize suitable comparison groups for ART birth health outcome studies: ovulation induction (OI), subfertile untreated, and fertile natural conceptions.
• To assess if pregnancy complications and adverse birth outcomes in ART births are elevated compared to subfertile (untreated and OI) conception groups.

Main Methods:

• Linked Western Australian State and Commonwealth datasets for births (≥20 weeks) from 2003-2014.
• Compared demographic characteristics, maternal conditions, obstetric history, and pregnancy complications across conception groups (ART, OI, subfertile untreated, fertile natural).
• Used generalized estimating equations to calculate adjusted risk ratios (aRRs) for singleton pregnancy complications and birth outcomes.

Main Results:

• Identified 9456 ART, 3870 OI, 11,484 subfertile untreated, and 303,921 fertile natural conceptions.
• OI and subfertile untreated groups shared more characteristics with ART than fertile groups, though differences persisted.
• ART singletons had higher risks of placental problems (e.g., placenta praevia aRR 2.42) and adverse outcomes (e.g., preterm birth aRR 1.38) versus subfertile untreated.
• OI singletons showed higher risks of preeclampsia and gestational diabetes, similar to the subfertile group.

Conclusions:

• Ovulation induction and subfertile untreated conception groups are valuable comparators for interpreting ART birth health outcomes.
• Pregnancy complications, especially placental disorders, and adverse delivery outcomes are more frequent following ART conception.
• These findings highlight the importance of selecting appropriate comparison groups in ART research.