This ‘retrospective observational’ study (which means a study where they look at people who were diagnosed with CHI and looked back to see if there was anything special about their pregnancies) looked at 33 pregnancies with confirmed ‘CHI’ in Toronto, Canada. They looked at blood results and ultrasound results as well as the overall health and characteristics of the mums and the outcomes of the pregnancies. Almost all the pregnancies (92%) delivered small for gestational age babies and 4/5 pregnancies were delivered before 37 weeks. They also found that more than would be expected number of pregnancies had high levels of alkaline phosphatase (a marker in blood tests) but these weren’t associated with stillbirths. Interestingly, and contradicting other studies, subsequent pregnancies didn’t seem to be affected by CHI although it appears they didn’t consider any pregnancies that ended in a miscarriage.
