Miscarriages linked to health risks in later pregnancies

New Curtin University research published in eClinicalMedicine has revealed a link between miscarriage and the increased risk of developing complications of gestational diabetes and high blood pressure-related disorders in later pregnancies.

Researchers from the Curtin School of Population Health analyzed 52 studies involving more than 4 million pregnancies across 22 countries to investigate the health impacts of miscarriage, abortion and recurrent pregnancy loss (more than two miscarriages in succession) on subsequent pregnancies.

The study found different health risks for each group.

People who had experienced a miscarriage were 44% more likely to develop gestational diabetes during later pregnancies but only 6% more likely to develop high blood pressure in subsequent pregnancies.

Conversely, people who had experienced recurrent pregnancy loss showed no increased risk of gestational diabetes but were 37% more likely to develop pre-eclampsia, a potentially dangerous complication characterized by high blood pressure, in later pregnancies.

There was no evidence linking abortion to diabetic or hypertensive-related issues, either during or outside of pregnancy.

Lead study author Dr. Jennifer Dunne said establishing the links between pregnancy loss, diabetes and high blood pressure could have a far-reaching impact.

"Miscarriages occur in 15–25% of all pregnancies—which is around 23 million per year, globally," Dr. Dunne said.

"Gestational diabetes and high blood pressure disorders in pregnancy can cause a variety of significant health problems; understanding the relationship between pregnancy loss and later pregnancy complications could reveal new ways to mitigate risks or possibly prevent these conditions from progressing.

"Further research into the biological links between pregnancy loss and later health issues might reveal new targets for developing treatments."

Dr. Dunne said the study added to what was already known about pregnancy complications and health later in life, even beyond pregnancy.

"Knowing miscarriage can lead to these pregnancy complications later on is important, as these conditions during pregnancy have previously been linked to a higher risk of people developing heart disease later in life," Dr. Dunne said.

"By shedding light on the long-term health effects of miscarriages and repeated pregnancy losses, this study paves the way for improved health care strategies, research, and support for those affected—hopefully enhancing the outcomes for parents and babies in future pregnancies."