Haem oxygenase‐1 (HO‐1), the rate‐limiting enzyme in haem degradation, plays a role in angiogenesis and vasculogenesis and is highly expressed in the placenta. Deficiencies in HO‐1 are associated with several pregnancy disorders, such as recurrent miscarriages and pre‐eclampsia. The unique combination of tissue protective, smooth muscle relaxing and angiogenesis regulatory properties makes HO‐1 a key player in the maintenance of a healthy pregnancy through a direct effect on placental structural and vascular development, thus affecting foetal development.
Conclusion: Therefore, we conclude that HO‐1 plays an important role in placental vasculature development and a deficiency in HO‐1 may contribute to pregnancy complications, such as pre‐eclampsia, spontaneous abortions and premature births.