Research
Obstetrics
Neurofibromatosis type 1 and pregnancy complications: a population-based study

Presented in part at the annual meeting of the Congress of Neurological Surgeons, Washington, DC, Oct. 1-6, 2011.
https://doi.org/10.1016/j.ajog.2013.03.029Get rights and content

Objective

The objective of the study was to determine whether vascular and other complications are more common in pregnant women with neurofibromatosis type 1 (NF1).

Study Design

We performed a population-based retrospective cohort study using the US Nationwide Inpatient Sample, 1988-2009, defining a cohort of pregnancy-related hospitalizations with an associated diagnosis of NF1 and comparing it with the control group not associated with NF1. Multivariable logistic regression was used to adjust for suspected confounders.

Results

Among 19 million pregnancy-related admissions between 1988 and 2009, we identified 1553 associated with NF1 (prevalence 0.008%). A diagnosis of NF1 in delivering mothers was associated with gestational hypertension (adjusted odds ratio [AOR], 1.6, 95% confidence interval [CI], 1.2–2.0), preeclampsia (AOR, 2.8, 95% CI, 2.3–3.4), intrauterine growth restriction (AOR, 4.6, 95% CI, 3.7–5.6), cerebrovascular disease (OR, 8.1, 95% CI, 2.6–25.4), preterm labor (AOR, 1.6, 95% CI, 1.4–1.9), and cesarean delivery (AOR, 2.0, 95% CI, 1.8–2.3). Women with NF1 were not significantly more likely to have deep venous thrombosis/pulmonary embolism, acute cardiac events, or stillbirth or to die during their hospitalizations compared with the general obstetric population.

Conclusion

NF1 was associated with increased maternal morbidity in pregnancy (including hypertensive and cerebrovascular complications) but not increased maternal mortality. Obstetricians should be aware of the potential for increased antenatal and peripartum complications among women with NF1.

Section snippets

Data source

The Nationwide Inpatient Sample (NIS) of the Healthcare Cost and Utilization Project (HCUP), sponsored by the Agency for Healthcare Research and Quality (AHRQ; Rockville, MD), collects administrative and clinical data on US hospital discharges yearly. The 2009 NIS, the most recent available data set, contains discharge data from 1050 hospitals in 44 states, approximating a 20% stratified sample of all nonfederal hospitals. Information available from the NIS includes up to 15 International

Results

We identified 19,750,702 pregnancy-related admissions that occurred between 1988 and 2009. Of these, 1553 were associated with a diagnosis of NF1; 1248 (80.4%) of NF1 admissions were also associated with a delivery. The proportion of delivery-associated hospitalizations associated with a diagnosis of NF1 was approximately 1 in 10,000. Table 1 summarizes the demographic characteristics of both the NF1 and general obstetric populations. As expected, the majority of women (80.8%) were between 20

Comment

In our study of more than 1500 pregnancy-related hospitalizations in patients with NF1, we found that pregnant women with NF1 have higher odds of gestational hypertension, preeclampsia, IUGR, and cerebrovascular complications. These risks persisted despite younger age and adjusting for multiple confounding factors such as preexisting chronic hypertension, diabetes, and renal disease. Because rates of chronic hypertension and renal artery stenosis are known to be higher in patients with NF1,

Acknowledgments

The purchase of databases and computing supplies was supported by the John and Cyndy Leahy Fellowship Fund. The corresponding author is grateful to Dr Robert Martuza of Massachusetts General Hospital and the Massachusetts General Hospital Neurosurgical Service for generous financial support of relevant coursework at the Harvard School of Public Health. The authors also thank Vanessa Merker, BS, of Massachusetts General Hospital, for assistance editing this manuscript.

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    A.R.T. received support from the John and Cyndy Leahy Fellowship Fund for the submitted work. The other authors report no conflict of interest. The funders had no role in the study design, data collection, data interpretation, or writing of the report.

    Cite this article as: Terry AR, Barker FG II, Leffert L, et al. Neurofibromatosis type 1 and pregnancy complications: a population-based study. Am J Obstet Gynecol 2013;209:46.e1-8.

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