Physiotherapist Beth Warren, 28, from Birmingham, challenged a storage time limit imposed by the UK fertility regulator.
She said it meant she had little over a year to conceive using sperm her husband Warren Brewer, who died of cancer aged 32 two years ago, placed in storage.
Mrs Warren, who uses her late husband's first name as her surname, asked a High Court judge to decide whether the sperm could be stored for a longer period.
Judge Mrs Justice Hogg ruled in Mrs Warren's favour yesterday.
Jenni Richards QC, representing Mrs Warren, said Mr Brewer wanted to ensure his sperm could be used by his wife after his death and had made his intentions clear.
The Human Fertilisation and Embryology Authority was later given permission to appeal against the ruling.