This BBC title is a click bait. It should have in the headlines a disclaimer that the person was using heavy drugs. The article says:
"When she arrived at hospital seeking treatment, Poolaw admitted to using illicit drugs while pregnant.
Later, the medical examiner's report, obtained by the BBC, found traces of methamphetamine in her unborn son's liver and brain.
The examiner did not determine a cause of death for the foetus, noting genetic anomaly, placenta abruption or maternal methamphetamine use could have been contributing factors."