Concern regarding the possibility that folate levels might be affected by light therapy, Dr. Kimball noted, has been put to rest by a new study showing that UVB phototherapy does not influence serum and red cell folate levels in psoriasis (J. Am. Acad. Dermatol. 2009;61:259–62).
The question of heat exposure has not been addressed, however. “There are recommendations against hot tubs and hot baths in the first trimester, for example, because of potential injury to the fetus, so if you have someone way up on the light scale, that might be something worth thinking about.”
Tumor necrosis factor inhibitors fall under third-line therapies. “Obviously we have limited data on these. They are generally risk category B, so most people feel reasonably comfortable if we had to go that direction, but there are potential risks that are unclear,” Dr. Kimball said.
Cyclosporine, which was the therapy of choice prior to the biologics era, is another third-line treatment, said Dr. Kimball. “Although cyclosporine is [risk] category C, we probably have the best information about this drug due to the transplant registries that are out there,” she noted.
It is associated with a low birth rate and prematurity, “so there are known risks associated with it, but malformations do not seem to be an issue.” Systemic steroids in the second and third trimester would be another third-line option if needed, she said.
Among the systemic therapies to avoid in pregnancy are PUVA, which can potentially lead to premature labor or fetal abnormalities; methotrexate, which is a teratogen and immunogen; and systemic retinoids, which are also known teratogens, Dr. Kimball said.
With respect to methotrexate in pregnancy, “the current recommendation extends to males, who should be advised to cease its use for 3 months prior to conception because of theoretical concern about chromosomal abnormalities,” she noted.
Regarding topical therapies, tazarotene, anthralin, calcipotriol, and coal tar should be avoided as well, said Dr. Kimball.
In all cases, putting a patient's risk into context is difficult given the limited and conflicting information that is available, Dr. Kimball said. “At the end of the day, you really have to guide women about the personal nature of these choices,” based on experience and the information that is available.
In order to improve research in this area, it is imperative that health care providers and patient advocacy organizations encourage individuals with psoriasis to enroll in pregnancy registries, Dr. Kimball stressed. “Pregnancy registries are one of our most valuable tools for collecting information about how to best manage and counsel women prepartum, during pregnancy, and post partum, yet they are so [undersubscribed]. This is something that we can help change.”
Dr. Kimball said she has served as a consultant and an investigator for Amgen Inc., Centocor Inc., Abbott Laboratories, NeoStrata Co., and Galderma; she is an investigator for Stiefel Laboratories Inc.; and she has a fellowship program funded by Centocor.