Scratching the womb is said to release hormones that make it more adhesive, but studies found it does not help women with fewer than two failed implants.
Assisted hatching (£615)
May help repeatedly unsuccessful couples by softening the embryo’s outer shell so it can ‘hatch’ more easily, but no evidence this works for older women.
Time-lapse monitoring (£775)
Camera shows up abnormalities by taking pictures as embryos develop, but no good quality evidence for routine use.
Embryo glue (£320)
Chemical with added hyaluronic acid developed to help the embryo ‘stick’ to the womb lining. May increase birth rates, but can also cause unplanned multiple births.
Intra-cytoplasmic sperm injection (up to £1,390)
Sperm injected directly into egg is said to help fertilisation, but experts argue this is not necessary if a man’s sperm is normal.
Intra-cytoplasmic morphological selected sperm injection (up to £600)
Uses a microscope almost 6,000 times more powerful than usual to identify any defects, but creates no more pregnancies than a basic sperm injection.
Immune therapy (£1,500)
Based on claim a woman may fail to become pregnant because her immune system rejects the embryo. A review found blood level of ‘natural killer’ cells, which fight infection, has no effect on implantation.
Pre-implantation genetic screening (£3,100)