Women who undergo thyroid or parathyroid surgery during pregnancy have more operative complications and require longer hospitalizations than do nonpregnant women who have such surgery, as well as relatively high rates of maternal and fetal complications.
These findings, from “the first population-based study to examine predictors of clinical and economic outcomes” in this patient group, suggest that thyroid and parathyroid surgery are not the low-risk procedures in pregnant women that they are in the general population, said Dr. SreyRam Kuy of Yale University, New Haven, Conn., and associates.
The investigators assessed thyroid and parathyroid procedures in pregnancy because the subject had not been well studied before now, even though most disorders that necessitate such surgery occur in women of childbearing age. In addition, recent attention has focused on developing practice guidelines for pregnant women with endocrine disorders, and there was a glaring lack of evidence on this issue in the literature.
Dr. Kuy and colleagues performed a retrospective cross-sectional analysis of hospital discharge data using “the largest all-payer inpatient database in the United States, with records from approximately 8 million hospital stays each year.” They compared outcomes of 201 pregnant women and 31,155 age-matched nonpregnant women who underwent the surgery for benign thyroid disease, malignant thyroid disease, and hyperparathyroidism between 1999 and 2005.
Pregnant patients had significantly higher rates of surgical complications (24%) than did nonpregnant women (10%), including double the rate of endocrine complications (16% vs. 8%). Pregnant women also had significantly longer median hospital stays (2 days vs. 1 day) and inpatient costs ($6,873 vs. $5,963).
In the subset of women who underwent thyroidectomy, those who were pregnant had a higher rate of surgical complications for both benign disease (27% vs. 14%) and malignant disease (21% vs. 8%), the investigators said (Arch. Surg. 2009;144:399-406).
Although these procedures are considered low risk in the general population, women who underwent thyroid or parathyroid surgery while they were pregnant had a relatively high rate of pregnancy complications. The maternal complication rate was 4.5%, and the fetal complication rate was 5.5%.
Pregnant patients of surgeons who performed a high volume of thyroid and parathyroid procedures showed significantly lower rates of both maternal and fetal complications than did those of less-experienced surgeons. In contrast, hospital volume exerted no effect on complication rates.
“It appears to be essential that pregnant patients who require thyroidectomy or parathyroidectomy be directed to high-volume surgeons to optimize their outcomes,” the researchers said.
Given these findings, the risks and benefits of thyroid and parathyroid surgery must be weighed carefully in pregnant women.
“Thyroidectomy is rarely indicated on an urgent basis unless there is significant concern about the well-being of the mother. For example, airway obstruction from large goiters in symptomatic pregnant women with already compromised breathing from uterine expansion, advanced differentiated thyroid cancer, and poorly differentiated cancers could justify proceeding to thyroidectomy prior to delivery,” the researchers advised.
Similarly, parathyroidectomy during pregnancy is indicated to protect the fetus and prevent neonatal hypoparathyroidism and tetany, they said.
This study was supported by the Robert Wood Johnson Foundation and the U.S. Department of Veterans Affairs. The investigators reported that they had no financial conflicts of interest.