Surrogates at greater risk of mental illness

Women acting as surrogates are more likely to develop mental illness during or after pregnancy than those carrying their own babies, new research suggests.

The study, based on Canadian health data, highlights the need for careful screening and support for gestational carriers throughout the process.

Researchers found the risk was also elevated among women with a prior history of mental illness, regardless of how they conceived.

Dr Maria Velez, first author of the research, said: “Our findings underscore the importance of adequate screening and counselling of potential gestational carriers before pregnancy about the possibility of a new-onset mental illness, or exacerbation of a prior mental illness during or after pregnancy,.

“As well, the provision of support during and after pregnancy may be particularly important for gestational carriers.”

The team from McGill University examined data from 767,406 births in Ontario between April 2012 and March 2021.

Of these, 758 involved surrogates, 748,732 were unassisted conceptions, and the remainder were IVF pregnancies in women carrying their own children.

Women with a previous mental illness diagnosis were excluded from the initial analysis.

The researchers compared the rate of new diagnoses from conception onwards, including anxiety, mood disorders, self-harm and psychosis.

After adjusting for factors such as maternal age, smoking, income and number of children, surrogates were found to have a 43 per cent and 29 per cent higher rate of new mental illness per 100 person-years than women with unassisted or IVF conceptions, respectively.

Mood and anxiety disorders were the most frequently diagnosed conditions across all three groups. The median time to diagnosis was around two and a half years.

The risk remained higher in surrogates, though less so, even when compared with women who had unassisted pregnancies but were no longer living with their child a year after birth.

Velez said: “The finding might suggest that some gestational carriers may experience grief from relinquishing their newborn, like that described after adoption or removal of the child into foster care – something that needs further studies.”

The team later included women with a prior record of mental illness in additional analyses.

These showed that all groups in this category had a higher rate of new-onset diagnoses compared with those who had no history of mental illness.

Although Canada requires psychological assessments for prospective surrogates, the data showed 19 per cent already had a documented mental health diagnosis before becoming pregnant.

The work builds on earlier findings by the same team showing higher rates of complications in surrogates, including severe postpartum bleeding and pre-eclampsia – a condition marked by high blood pressure during pregnancy.

Dr Zaina Mahmoud, a University of Liverpool expert on surrogacy’s socio-legal aspects who was not involved in the study, said more research was needed to understand the causes of the elevated risk.

“[The researchers are] not addressing why or how surrogates have these emotional trajectories,” she said, noting their broad definitions of mental illness.

“They hypothesise that grief from relinquishing the infant may contribute, but they don’t actually measure that grief.”

However, Mahmoud supported the call for extended support and monitoring of surrogates beyond the standard postnatal period.

The findings, she said, “really highlight the need for robust information and consent procedures.”