Women who underwent infertility treatment had a slightly higher risk for complications, according to a Canadian study.
Comparing 11,500 pregnancies in women resulting from infertility treatments with pregnancies in women who did not receive treatment, invasive and noninvasive treatments were tied to a higher risk for severe maternal morbidity or mortality (RR 1.39, 95% CI 1.23-1.56), reported Natalie Dayan, MD, of McGill University Health Centre in Montréal, and colleagues.
However, the chance of a women having three or more indicators of severe maternal morbidity — the most common of which were severe postpartum hemorrhage, admission to the ICU, puerperal sepsis, hysterectomy, or cardiac issues — was only raised for those who underwent invasive treatment, such as in vitro fertilization (IVF, OR 2.28, 95% CI 1.56-3.33).
Noninvasive treatments, such as intrauterine insemination, were not tied to this elevated risk (OR 0.99, 95% CI 0.57-1.72), the group wrote in CMAJ.
“Whether specific components of treatment using in vitro fertilization, such as the dose of ovarian hyperstimulation or fresh versus frozen embryo transfer, worsened maternal health, or whether the increased risk is a reflection of those who require or choose in vitro fertilization, remains to be determined,” Dayan’s group wrote.
For this analysis, the researchers compared a composite outcome of severe maternal morbidity or maternal death from week 20 of gestation through 42 days postpartum. The cohort included women who underwent either invasive or noninvasive infertility treatments from 2006 to 2012, including IVF, ovulation induction, intrauterine insemination, or intracytoplasmic sperm injection. They were compared with nearly 50,000 naturally-conceived pregnancies.
The women who underwent infertility treatment were older and had higher incomes. Also, a greater proportion were nulliparous or pregnant with multiple gestation.
The authors reported that severe maternal morbidity or maternal death occurred in 356 infertility-treated pregnancies, or 30.8 per 1,000 deliveries, versus 1,054 untreated pregnancies, or 22.2 per 1,000 deliveries.
Eric Flisser, MD, of the Icahn School of Medicine at Mount Sinai and Reproductive Medicine Associates of New York, both in New York City, pointed out that “what is already known, and also correctly pointed out by the study authors, is that both types of infertility treatment — insemination and IVF — are, in general, extremely safe procedures.”
Flisser, who was not involved with the study, told MedPage Today that it was important to bear in mind “patients undergoing more advanced infertility treatments, such as IVF, may represent a group who have worse maternal health or who have higher risk factors associated with pregnancy complications than other patients, such as those who underwent treatment by intrauterine insemination and those who did not need any infertility treatment at all.”
“A potential reason for the distinction between patients who successfully conceived by insemination compared to IVF is … ‘healthier’ patients may conceive via insemination and only the ‘less healthy’ may progress, in some cases, to IVF,” he explained, underscoring how the patient population who undergo invasive versus noninvasive infertility treatments are clinically distinctive.
“Patients who start with IVF may have previously failed other treatments, which makes the IVF patient group different from the insemination group,” Flisser noted. “For example, patients undergoing insemination for the most part do not represent patients who had previously tried IVF. Therefore, these two groups — insemination versus IVF — likely have different risk characteristics, which means that there is a real possibility that patients needing IVF are already at higher risk of pregnancy complications.”
Flisser also noted that the naturally-conceived pregnancy group in this study may have been healthier in general. “The authors point this out by showing that women who underwent infertility treatments were more likely to have conditions known to cause poor pregnancy outcomes,” he said.
The authors suggested future studies aimed at identifying specific clinical patient factors that may impact this associated risk.
The study was supported by the Canadian Institutes of Health Research.
Dayan and co-authors disclosed no relevant relationships with industry.