Women who act as gestational surrogates appear to be at greater risk of health complications than those who carry their own babies, researchers have found.
The use of surrogates, or “gestational carriers”, has flourished in recent years, with figures for England and Wales revealed that the number of parental orders, which transfer legal parentage from the surrogate, rose from 117 in 2011 to 413 in 2020.
A study based on data from Canada suggests that surrogates are more likely to experience complications, including severe postpartum bleeding and severe pre-eclampsia, than women who conceived naturally or with IVF. Babies were more likely to be born prematurely to surrogates, although they were no more likely to have serious neonatal complications.
Experts say the findings highlight the need for improved prenatal care for surrogates, and the creation of strict criteria and regulations for women who want to fill such a role.
Dr Maria Velez, the first author of the research, from McGill University in Canada, said it was important to advise the intended parents and the gestational carriers about possible complications.
“Those complications are important for [gestational carriers],” she said. “But they also have an impact for the intended parents, [and] for the physician caring for this patient.”
Write in the journal Annals of Internal MedicineVelez and colleagues report how they used the Better Outcomes Registry & Network (Born) database to examine the incidence of complications among 863,017 singleton births in Ontario that occurred from 2012 to 2021.
Of these births, the team reported that 806 babies were born from surrogates — which typically involved receiving an embryo from the intended parents — 846,124 were the result of unassisted conception and 16,087 involved IVF.
The team found that the rate of serious maternal health complications was 7.8% for surrogates, 2.3% among the unassisted group and 4.3% for pregnancies involving IVF.
While the researchers found that surrogates were more likely to have certain characteristics, including having given birth before, living in a lower-income area, being obese and having high blood pressure, such factors did not appear to fully explain the results .
Indeed, after taking into account factors such as age, level of income, number of previous births, obesity, smoking and high blood pressure, the team found that the risk of severe postpartum hemorrhage was 2.9 times higher for surrogates compared to women who conceived unassisted, while the risk of giving birth before 37 weeks was 1.79 times higher. Such risks were also higher, although to a lesser extent, for surrogates compared to women who had undergone IVF.
“It may be that there are other mechanisms, including perhaps an immunological mechanism, that may be involved in this higher risk [for gestational carriers],” Velez said.
Jackie Leach Scully, a professor of bioethics at the University of New South Wales, who was not involved in the study, noted that the research had limitations, including that it included only a small group of surrogates, and that such women may have been healthy. babies who previously had no health problems during pregnancy.
“However, what this article highlights is that we actually know relatively little about the specific risks of harm to the surrogate woman, or the baby, in surrogacy,” she said, adding that although a surrogate should ideally be healthy and with a low risk of complications, which did not always happen in practice.
“This raises some ethical questions, firstly about the potential exploitation of women who act as gestational carriers and who effectively bear the risks of pregnancy on behalf of someone else,” she said.
“Secondly, the scarcity of accurate data on the risks and outcomes of surrogate pregnancies should really make us question how seriously the health of women, as opposed to the health of the fetus or baby, is taken. The neglect of women’s health in the history of medicine is well recognized, and can be exacerbated in the situation of surrogacy, where the gestational carrier’s role is socially obscured.”
