Pregnancy and breast cancer. According to a new Canadian study, pregnancy has no negative correlation to the survival rates of women who’ve been diagnosed with breast cancer.
The study took place over a five-year period and was conducted by Steven A. Narod, a senior scientist at the Women’s College Research Institute and five others with the overall objective of comparing the survival rates of women who had breast cancer during or after pregnancy as opposed to those who were diagnosed but did not become pregnant at any point.
Looking at 7,500 Ontario breast cancer patient’s medical records who were female, aged 20–44, and treated between the years of 2003–2014.
The study found that there was an 88 per cent survival chance of woman who were never pregnant, 82 per cent if pregnant during diagnosis, and a 97 per cent survival rate for those who became pregnant 6 months or more after diagnosis. Ontario accounted for 39 per cent of breast cancer cases in 2016.
“We demonstrated a strong effect of age on survival in all hazard estimates, and young women do relatively badly. About 20 per cent to 25 per cent of the cases end with the mother, unfortunately, dying of her cancer,” Narod said to HemOnc.
Women who had been pregnant before their diagnosis or pregnant at the time of diagnosis, and were between the ages of 20-29 had a much higher mortality rate than those aged 30–39.
“We were surprised that pregnancy after breast cancer seemed to reduce the risk of the cancer coming back, however, we need to confirm this,” added Narod..
According to the Canadian Cancer Society, in Canada in 2016 there were 25,700 new cases of breast cancer reported amongst women for the year, with a survival chance of 87 per cent. But its research notes that it may become more difficult to find and diagnose breast cancer if the patient is pregnant at the time.
Narod points out that one of the main questions asked at the time of diagnosis is if pregnancy will be possible and safe after treated. Before now the answer was usually yes, but suggested to wait a couple years after treatment was complete. But that timeframe looks to be much shorter now.
“You’d want to be finished your treatment. You certainly don’t want to be pregnant while you’re on chemotherapy or (the drug) tamoxifen, which is considered possibly hazardous to the baby,” Narod said.
Several sources also suggest women should consider cryogenically storing their eggs before undergoing chemotherapy due to the effects that it can have on a female’s fertility.
“You get the impression that pregnancy and breast cancer are a bad thing. It may, in fact, be that pregnancy actually reduces the number of deaths from breast cancer, but we don’t see it because the ones that it doesn’t prevent are the ones that are more likely to go on and be fatal.” Said Narod expressing the need for more research.
Thankfully the mortality rate for breast cancer has decreased over recent years and is continuing to do so.