Congenital varicella syndrome has occurred in newborns of women who experienced varicella disease following infection with wild-type varicella zoster virus during their pregnancies.1,2 Congenital varicella syndrome is characterized by cutaneous scarring in a dermatome distribution and/or hypoplasia of an extremity.3 Additional manifestations my include low birth weight, microcephaly, localized muscular atrophy, ocular anomalies, and neurological abnormalities.3 The risk of congenital varicella syndrome is estimated to be approximately 0.4% when maternal infection occurs from conception through the 12th week of gestation, and 2% when infection occurs between the 13-20th week of gestation.2
The Pregnancy Registry for VARIVAX® was established in 1995 as a collaborative effort between Merck & Co., Inc. and the Centers for Disease Control and Prevention to assess the risks of congenital varicella syndrome and other birth defects in the offspring of women who inadvertently received VARIVAX within 3 months prior to conception or at any time during pregnancy. In 2006, PROQUAD and ZOSTAVAX, which also contain attenuated varicella zoster virus, were added to the Registry.
The Pregnancy Registry receives voluntary reports from health care providers or consumers about women given the vaccine three months prior to or at any time during pregnancy. Pregnancies are followed and outcomes obtained from participating clinicians.
Health care providers are encouraged to report cases of prenatal exposure as early in pregnancy as possible to facilitate the collection of prospective, unbiased information. Enroll your patient by downloading and completing the one-page enrollment form attached. You will be asked to complete a second one-page Outcome of Pregnancy form at the end of the pregnancy. We provide you with a one-page consent form that explains the Pregnancy Registry to your patient. We encourage you to review it with your patient and have her sign it before the end of her pregnancy. All forms can be faxed (or mailed) to the Pregnancy Registry.
Criteria for enrollment include:
- A report of pregnancy from a patient or health care provider (U.S., Canada and Puerto Rico)
- Exposure to VARIVAX, PROQUAD, and ZOSTAVAX during pregnancy (within 3 months prior to or at anytime after the woman's last menstrual period)
- Name of a health care provider (to confirm diagnoses and to obtain outcome information)
- Name of the patient or, if you wish to keep the report confidential, patient initials and birth date or chart number to allow for follow-up at the expected date of delivery
Aggregate data from the Registry is used to respond to inquiries from health care providers who call to request information on the use of a product during pregnancy. Data may be published or used to update the pregnancy section of the product label, as appropriate. Dissemination of data collected in the Registry is done without compromising individual patient confidentiality. Information from the Registry is shared, as required, with regulatory authorities (e.g., FDA).
Reports of the aggregate data in the Registry are updated annually and are available to health care providers in the U.S. upon request. (In countries outside of the U.S., information is available through the local Merck subsidiary). To request a report, call the 800 number below or download and complete the attached Annual Report Request Form and fax it to the Registry. Please include your fax number and a report will be sent to you within 3 business days.
Merck does not recommend the use of its products in any manner other than as described in the product circular. Please review the full prescribing information before prescribing VARIVAX, PROQUAD, and ZOSTAVAX.
VARIVAX Prescribing Information
PROQUAD Prescribing Information
ZOSTAVAX Prescribing Information
Pregnancy Registry for Varicella Zoster Virus-containing Vaccines
1 Laforet EG and Lynch CL. Multiple congenital defects following maternal varicella: report of a case. New Engl J Med 1947: 236: 534-37.
2 Enders G, Miller E, Cradock-Watson J, Bolley I, Ridehaigh M. Consequences of varicella zoster in pregnancy: Prospective study of 1739 cases. Lancet 1994; 343:1547-1550.
3 Roberts RM. Fetal effects from varicella-zoster. In: Buyse ML, editor. Birth defects encyclopedia. Cambridge, MA: Blackwell Scientific Publications; 1990. p. 708-710.