Vascular dimorphism ensured by regulated proteoglycan dynamics favors rapid umbilical artery closure at birth.

The umbilical artery lumen closes rapidly at birth, preventing neonatal blood loss, whereas the umbilical vein remains patent longer. Here, analysis of umbilical cords from humans and other mammals identified differential arterial-venous proteoglycan dynamics as a determinant of these contrasting vascular responses. The umbilical artery, but not the vein, has an inner layer enriched in the hydrated proteoglycan aggrecan, external to which lie contraction-primed smooth muscle cells (SMC). At birth, SMC contraction drives inner layer buckling and centripetal displacement to occlude the arterial lumen, a mechanism revealed by biomechanical observations and confirmed by computational analyses. This vascular dimorphism arises from spatially regulated proteoglycan expression and breakdown. Mice lacking aggrecan or the metalloprotease ADAMTS1, which degrades proteoglycans, demonstrate their opposing roles in umbilical vascular dimorphism, including effects on SMC differentiation. Umbilical vessel dimorphism is conserved in mammals, suggesting that differential proteoglycan dynamics and inner layer buckling were positively selected during evolution.

First-trimester and second-trimester screening at a community hospital: experience from the first year of implementation.

OBJECTIVE: To review the first-year experience implementing a new early screening during pregnancy program for aneuploidy in a community hospital and compare this program with the screening program immediately preceding its implementation. METHODS: The electronic medical records of all pregnant patients referred from May 17, 2005, through December 31, 2006, for genetic counseling were reviewed for maternal characteristics, indication for referral, a priori and adjusted risk of aneuploidy, and patient choice for screening or testing. The new early screening program (nuchal translucency group) consisted of additional educational materials, nuchal translucency, serum biochemical analytes, quad screening, and invasive testing when indicated. This cohort was compared with the patients who received traditional genetic screening or testing (pre-nuchal translucency) immediately preceding the nuchal translucency program. RESULTS: A total of 101 patients were included in the pre-nuchal translucency group compared with 359 patients in the nuchal translucency group. The most common reason for referral was advanced maternal age; there were no differences in the maternal characteristics between the two groups. Forty-six percent of patients in the early screening program underwent an invasive procedure compared with 76% in the pre-nuchal translucency group (odds ratio 0.26, 95% confidence interval 0.15-0.42; P<.001). CONCLUSION: Early screening programs in a single community hospital are feasible and appear to result in a significant reduction in the number of invasive procedures with excellent patient satisfaction and acceptance.

Management of group B Streptococcus in pregnant women with penicillin allergy.

OBJECTIVE: To determine whether group B Streptococcus (GBS)-colonized pregnant women who report a history of penicillin allergy can safely undergo diagnostic evaluation to rule out or confirm the potential for an IgE-mediated (allergic) reaction to penicillin. STUDY DESIGN: Over 18 months, all pregnant women with GBS-positive vaginal/rectal cultures and a history of penicillin allergy were referred to the Department of Allergy and Immunology for a history and possible skin testing. Patients who had experienced anaphylaxis were advised to continue avoiding penicillin and were not skin tested. Women without such a history underwent immediate hypersensitivity (percutaneous and intradermal) testing using 2 penicillin reagents with controls. If skin testing was negative, intrapartum antimicrobial prophylaxis with intravenous penicillin was administered. RESULTS: Of 28 patients with both GBS colonization and "penicillin allergy," 25 (89%) had negative skin testing to penicillin and received intrapartum penicillin for GBS prophylaxis without adverse reactions. Skin testing was positive in 2 patients, and intrapartum penicillin was not administered. Penicillin skin testing was not performed on 1 patient due to a history of anaphylaxis from penicillin. CONCLUSION: These results indicate that most pregnant women reporting penicillin allergy undergo negative skin tests and are able to safely receive intrapartum penicillin GBS prophylaxis.

Development of an outpatient clinic to provide pertussis vaccinations to maternity patients and family members.

PURPOSE: The implementation of a hospital-based outpatient pertussis prevention program targeting maternity patients and family members is described. SUMMARY: Faced with a rising incidence of pertussis statewide, a large Ohio hospital formed a multidisciplinary team to ensure hospital compliance with current guidelines calling for administration of the tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis (Tdap) vaccine to all maternity patients as well as previously unvaccinated family members and likely neonatal caregivers (i.e., "cocooning"). The team had regularly scheduled meetings to identify and address fiscal, logistic, and practice-related challenges throughout the implementation process. Key challenges included (1) determining the availability of insurance reimbursement for Tdap vaccination services, (2) cultivating support for the vaccination initiative among obstetrics and maternal-fetal medicine specialists, (3) coordinating development and dissemination of educational information to patients and their families at specified points of contact, and (4) establishing an efficient registration process for family members. The outpatient vaccination clinic was located adjacent to the hospital's maternity center in order to provide convenient access. Despite limited clinic hours (three hours daily on weekdays only) and ongoing reimbursement and funding challenges, the program has improved Tdap vaccination rates in the target population and is considered a successful demonstration of the cocooning concept. CONCLUSION: Implementation of an outpatient clinic for neonatal pertussis prevention was well accepted by family members of newborns, and Tdap vaccinations were administered to 329 family members during the first 11 months of clinic operations.