Perinatal Outcomes and Assisted Reproductive Technologies

Assisted reproductive technologies encompass a range of interventions, including in vitro fertilisation and intracytoplasmic sperm injection, that enable conception in couples facing infertility. Although these techniques have transformed reproductive medicine and contributed to millions of births worldwide, they are associated with an increased incidence of maternal and neonatal complications. Key maternal risks include gestational diabetes, hypertensive disorders, placenta previa and placental abruption. Neonates conceived by these methods exhibit higher rates of preterm birth, low birth weight and small-for-gestational-age status. Underlying mechanisms may involve embryo culture conditions, hormonal preparation of the endometrium and epigenetic changes linked to fresh versus frozen embryo transfer. Multiple gestations further amplify adverse outcomes, prompting the adoption of elective single embryo transfer to reduce twin and higher-order births. Ongoing research aims to refine protocols, minimise perinatal morbidity and guide obstetric management to optimise outcomes for both mother and child.

Research from Nature Portfolio

One large retrospective cohort study matched pregnancies conceived by assisted reproduction with naturally conceived controls, revealing that singleton births after in vitro fertilisation or intracytoplasmic sperm injection faced significantly higher odds of gestational hypertension, preeclampsia, placenta previa, preterm labour and low birth weight. These risks persisted after adjusting for maternal age and parity, indicating that procedural factors contribute independently to adverse outcomes.

A chorionicity-based analysis of twin gestations following assisted conception found that monochorionic diamniotic twin pregnancies exhibited an elevated risk of preterm premature rupture of membranes, while dichorionic diamniotic twins showed increased rates of intrahepatic cholestasis of pregnancy. Despite these differences, overall perinatal morbidity and neonatal outcomes were comparable to those in spontaneously conceived twins when managed in specialised centres.

Perinatal Outcomes and Assisted Reproductive Technologies publication trend

The graph below shows the total number of articles in perinatal outcomes and assisted reproductive technologies across all publications each year (not limited to Nature Index journals).

Technical terms

Assisted reproductive technologies (ART): Medical procedures used to achieve pregnancy, including ovarian stimulation, egg retrieval, fertilisation in vitro and embryo transfer.

Cryopreservation: The process of freezing embryos or gametes at very low temperatures for future use, often associated with improved endometrial synchrony.

Placenta previa: A condition in which the placenta partially or wholly covers the cervix, increasing the risk of bleeding during pregnancy and delivery.

Chorionicity: The number of placentas in a multiple pregnancy, classified as monochorionic (shared placenta) or dichorionic (separate placentas), influencing perinatal risk.

Elective single embryo transfer (eSET): A strategy of transferring a single embryo during assisted reproduction to reduce the likelihood of multiple pregnancies and related complications.

References

1. Risk of placenta previa in assisted reproductive technology: A Nordic population study with sibling analyses. PLOS Medicine (2025).
2. Maternal and Live-birth Outcomes of Pregnancies following Assisted Reproductive Technology: A Retrospective Cohort Study. Scientific Reports (2016).
3. Assisted reproductive technology and hypertensive disorders of pregnancy: systematic review and meta-analyses. BMC Pregnancy and Childbirth (2021).
4. Absolute Risk of Adverse Obstetric Outcomes Among Twin Pregnancies After In Vitro Fertilization by Maternal Age. JAMA Network Open (2021).
5. Clinical outcomes after assisted reproductive technology in twin pregnancies: chorionicity-based comparison. Scientific Reports (2016).