The risk of in-hospital complications and poor birth outcomes were greater in pregnant women with current or historical cancer diagnoses, new research suggests.
The study, published in Mayo Clinic Proceedings, found that women with current and historical cancer diagnoses had an increased risk of death, kidney injury, and stroke during delivery hospitalizations, compared with those with no cancer. When it came to delivery outcomes, this group also had a higher risk for preterm birth and postpartum hemorrhage. Those with a current cancer diagnoses had a 1.7-fold increase in odds for a preterm birth, compared with women without cancer.
“Our study found that metastases increased the odds of mortality, cesarean delivery, preterm birth, and stillbirth,” the researchers noted. “Coupled with previous research reporting that pregnant women are more likely to be diagnosed with advanced disease, this implies that pregnant women with newly diagnosed cancer have poor prognoses.”
However, although women with prior cancer had increased odds of mortality, the researchers said it was not statistically significant.
“The study really did not show an increase of mortality [for women with prior cancer diagnosis],” said Justin Chura, MD, a specialist in gynecologic oncology who was not involved in the study. “And the reason might be because there is not or the reason might be because it’s such a rare event. You would need 100 million births to assess that. So I would actually use caution in that interpretation.”
Researchers analyzed more than 43 million delivery hospitalizations of women with or without current or historical cancer diagnoses between January 2004 and December 2014. They found that the most common cancer diagnoses were hematologic, thyroid, cervical, skin, and breast.
Of the five most common cancers, the prevalence of all maternal complications and negative delivery outcomes was the highest among women with hematologic cancers. They were more likely to experience peripartum cardiomyopathy, acute kidney injury, and arrhythmia, compared with other cancers. Postpartum hemorrhage, maternal mortality, and placental abruption was also more likely to occur in those with this type of cancer.
“I was surprised that it was the hematologic cancers that were worse when they did it by cancer type,” said Dr. Chura, who is the chief of surgery and the director of gynecologic oncology and robotic surgery at the Cancer Treatment Centers of America’s Eastern Regional Medical Center in Philadelphia. “I think this is a useful bit of information for counseling our patients and also to identify the cohort with the highest risk.”
The findings also suggested that those with skin cancer had the highest odds for stroke, while women with cervical and breast cancers were more likely to experience acute kidney injury and preterm birth.
Dr. Chura said cancer treatments can have an impact on a woman’s health when she’s giving birth. For example, if a woman is diagnosed with cervical cancer, doctors may perform a cone biopsy on her where they remove a large portion of the cervix and still leave them with the ability to conceive and become pregnant. However, those patients are left with a higher risk of a preterm delivery.
For women with a hematologic cancer like non-Hodgkin’s lymphoma, chest radiation may cause some subsequent damage to their heart muscles “and now the stress of pregnancy puts more demand on the heart that can lead to cardiac complications for that patient,” Dr. Chura said.
“There are potential long-term effects from radiation and chemotherapy,” Dr. Chura said.
Previous studies have shown that chemotherapy may affect pregnancy and delivery. A 2019 study published in the Journal of Cancer also found that 59 pregnant women with cancer had increased mortality compared with those without the long-term illness. Meanwhile, another 2018 study published in Cancer found that women who conceived less than a year after starting chemotherapy had higher risks of preterm birth in comparison with those who conceived more than a year after starting chemotherapy. The study also found that cancer survivors who conceived more than a year after finishing chemotherapy with or without radiation had no higher risk of a preterm birth than those without cancer.
Dr. Chura said the new study could force doctors to think about the long-term effects of their cancer therapies and make them more apt to think about how to make cancer therapy less toxic with less long-term health consequences, while still curing patients.
“Most oncologists, when dealing with younger patients, are very focused on curing the cancer at hand, but not necessarily thinking 5 or 10 years down the road,” Dr. Chura said. “[This study] could help inform or at least make us aware of the long-term consequences of our cancer therapies.”
Dr. Chura had no relevant financial disclosures.