A coroner says doctors should warn patients of the blood clotting risks of the contraceptive pill following the deaths of two young women.

Two women died in the same month in New Zealand from similar complications of taking the contraceptive pill prompting a coroner to recommend counselling on the risks of venous thromboembolism. Both of the women had unknown blood clotting conditions.

One of the women, Georgia O'Neill, a 24-year-old makeup artist, was found dead in her room at her shared flat in Mount Roskill Auckland by her housemate in September 2021. Ms O'Neill had texted her housemate and her dad earlier in the day to say she wasn't feeling well and had pain in her lower back running down her left leg. She told her housemate the pain made her want to throw up.

A second young woman Isabella Rangiamohia Alexander, 17,collapsed during a walk with her father in the same month. She was rushed to Auckland Hospital but died shortly after. Blood clots were later found on her legs and lungs.

Coroner Ho said Ms O'Neill was unaware she had a condition known as Factor V Leiden mutation which increases the risk of deep vein thrombosis (DVT) or pulmonary embolism (PE) to those taking the pill by 35 times. For those without the condition who take the pill the risk is about three-to-fourfold.

Dr Eileen Merriman, clinical director of haematology and lead thrombosis clinician at Te Whatu Ora Waitematā, said there is no benefit to routinely screen for Factor V Leiden before patients go on the contraceptive because most people who developed a DVT or PE do not have the thrombophilic mutation.

"The absence of a positive test may therefore falsely reassure those with a family history of venous thromboembolism where concomitant risk factors might be present" Dr Merriman said, reports the NZ Herald. The Coroner recommended all women who took the combined contraceptive pill and particularly those with a family history of venous thromboembolism should be vigilant about monitoring for symptoms.

He said women should be properly counselled about the increased risk and the symptoms to watch out for by doctors before they are prescribed the pill but said the that an unintended preganancy could create an even greater risk. "The risk of DVT and PE in pregnancy is sixtyfold higher than that from the combined oral contraceptive pill." Dr Merriman's report said.

DVT symptoms include leg pain in the thigh or calf, swelling, skin that is hot to the touch and has reddish discolouration or streaks. PE symptoms include shortness of breath, rapid breathing, chest pain under the ribcage, dizziness and fainting.