The study, published on bmj.com, took data from 23,500 women who had IVF and 117,000 women with natural pregnancies and found that:
- 4.2 out of every 1,000 women who had IVF suffered blood clots
- compared with 2.5 of every 1,000 with natural pregnancies
- pulmonary embolism occurred in 8.1 women out of every 10,000 who have IVF
- compared with six out of 10,000 who get pregnant naturally
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