when compared against women with epilepsy who planned their pregnancy, according to recent results from a retrospective study published in JAMA Neurology.
Dr. Andrew Herzog
“This analysis adds the finding that unplanned pregnancy may increase the risk of [spontaneous fetal loss] in women with epilepsy and identifies pregnancy planning, maternal age, and interpregnancy interval as significant modifiable variables,” Andrew G. Herzog, MD, of the Harvard Neuroendocrine Unit at Beth Israel Deaconess Medical Center in Wellesley, Mass., and colleagues wrote in their study.
The researchers examined results from a web-based survey completed by 1,144 women in the Epilepsy Birth Control Registry (EBCR) between 2010 and 2014 with data on contraception use, pregnancy history, and antiepileptic drug (AED) treatment. Patients were aged 18-47 years (mean 28.5 years) with 8.7% of the cohort consisting of minority women and 39.8% having household incomes of $25,000 or less.
Pregnancy history data included number of pregnancies, number of planned or unplanned pregnancies, AED type used during pregnancies, pregnancy outcomes such as live birth, induced abortion, and spontaneous fetal loss (SFL), while AED data included categorizing patients into no therapy, monotherapy, and polytherapy groups. AED use was further subdivided into no AED, enzyme-inducing AED, non–enzyme-inducing AED, enzyme-inhibiting AED, glucuronidated AED, and mixed category groups.
Of 794 pregnancies, 530 pregnancies (66.8%) were unplanned and 264 (33.2%) were planned, with 473 live births (59.6%), 141 induced abortions (17.8%), and 180 SFL (22.7%). Among patients who did not have an induced abortion, SFL risk was higher if the pregnancy was unplanned (137 patients, 35.0%), compared with those who planned (43 patients, 16.4%) their pregnancy (risk ratio = 2.14; 95% confidence interval, 1.59-2.90; P less than .001). According to a regression analysis, SFL risk was higher for patients where “planning was entered alone” in unplanned pregnancies (odds ratio = 2.75; 95% CI, 1.87-4.05; P less than .001) as well as when adjusted for AED category, maternal age, and interpregnancy interval (OR = 3.57; 95% CI, 1.54-8.78; P = .003).
There was an association between maternal age (OR = 0.957; 95% CI, 0.928-0.986; P = .02) and risk of SFL, with lower risk seen in the 18- to 27-year-old group (118 patients, 29.5%; RR = 0.57; 95% CI, 0.39-0.84; P less than .004) and 28- to 37-year-old group (44 patients, 20.8%; RR = 0.40; 95% CI, 0.26-0.62; P less than .001), compared with the under-18 group (15 patients, 51.7%). There was also a higher risk of SFL with regard to interpregnancy interval (OR = 2.878; 95% CI, 1.8094-4.5801; P = .008), with a greater risk seen if the interpregnancy interval was under 1 year (56 patients, 45.9%), compared with 1 year (56 patients, 22.8%) or higher (RR = 2.02; 95% CI, 1.49-2.72; P less than .001).
“In view of the finding of increased risk for SFL in unplanned pregnancies in women with epilepsy, and because a history of SFL in women with epilepsy may increase the risk that subsequent live-born offspring will develop epilepsy, the finding warrants prospective investigation with medical record verification of pregnancy outcomes,” Dr. Herzog and his colleagues wrote.
The Epilepsy Foundation and Lundbeck funded the study. Dr. Herzog reports support by grants, and two coauthors received salary support from grants, from the two organizations.
SOURCE: Herzog AG et al. JAMA Neurol. 2018 Oct 15. doi: 10.1001/jamaneurol.2018.3089.