IVF linked to blood clot risk

Tags: pregnancy

Women are more likely to suffer blood clots during pregnancy if the conception was assisted by in vitro fertilisation (IVF), according to Swedish research.

Scientists found that 4.2 out of every 1,000 women who had IVF suffered from blood clots, compared to 2.5 out of every 1,000 who got pregnant naturally.

They examined a total of 23,500 women who had IVF and 117,000 women who had conceived naturally to compile their findings, which have been published on

Other findings revealed that the risks of suffering a pulmonary embolism, or fatal blood clot, increased sevenfold during the early stages of a pregnancy among women who had IVF.

Researchers noted that pulmonary embolisms occurred among 8.1 women out of every 10,000 who had IVF compared to six out of 10,000 who conceived naturally.

Around 10% of couples globally are affected by infertility and an estimated five million people have been born as a result of IVF, which involves eggs being removed from ovaries, fertilised with sperm in a lab and then being placed in the woman's womb.

Increased risk of blood clots has been known to be factor during pregnancies, but this study set out to determine how having IVF impacted on that.

Results showed a higher risk of blood clots across an entire pregnancy, although this differed between the trimesters with the biggest risk during the first three months.

Visit the Pregnancy and Childcare Centre for more information on pregnancy and child health or visit our Heart Centre for information on heart conditions.

Copyright Press Association 2013

back to top

Ask the expert

Got a question?
Our team of medical experts are ready to help.