Electrical pacemaker as a safe and feasible method for decreasing the uterine contractions of human preterm labor.

AIM: The aim of the study was to test the safety and feasibility of a system designed to decrease the uterine contractions of human preterm labor using a weak electrical current. METHODS: Patients in preterm labor had an electrode catheter placed in the posterior vaginal fornix and attached to an electrical pacemaker. Contraction intervals were determined during the 60-min study, in which minutes 0-20 was the preintervention control period (C1); 21-40 was the electrical intervention (EI), with a 10-s burst of current administered just before each expected contraction; and 41-60 was the postintervention control (C2). Mean intervals were calculated and compared mixed-model ANOVA. RESULTS: Five patients were studied. No maternal or fetal vital sign irregularities were seen. All the babies had a normal neonatal intensive care unit stay for gestational age. The respective mean contraction intervals for C1, EI, and C2 and their within- and between-subject standard deviations were 4.64 (±0.81, ±2.45), 5.71 (±3.03, ±1.62), and 3.83 (±0.83, ±1.31) min. There was a significant difference between EI and C2 (P=0.0078) and no difference between C1 and C2 or between EI and C1 (P=0.1373). CONCLUSIONS: EI appears to be a safe and feasible method for decreasing preterm contractions. To confirm and test effectiveness, longer interventions and additional cases are needed.

Tenofovir disoproxil fumarate for prevention of vertical transmission of hepatitis B virus infection by highly viremic pregnant women: a case series.

BACKGROUND: Despite appropriate immunoprophylaxis, up to 10 % of infants born to highly viremic hepatitis B virus (HBV-DNA ≥ 7 log IU/mL) mothers are infected with HBV. Use of TDF to prevent vertical transmission (VT) by such mothers has not been evaluated. PURPOSE: To evaluate the efficacy and safety of TDF in preventing VT from highly viremic HBV-infected mothers. METHODS: Data were collected retrospectively from HBV mono-infected, hepatitis B e antigen (HBeAg) positive, pregnant women between 6/2008 and 11/2010. Cases enrolled were HBV mono-infected mothers who received TDF (300 mg orally once a day) in the third trimester. Those with pregnancy complications or an abnormal fetus on sonography were excluded from use of TDF. All infants received hepatitis B immunoglobulin and vaccination at birth and subsequently. RESULTS: Eleven Asian mothers received TDF at the median gestational age of 29 (28-32) weeks and the median duration of TDF use before delivery was 10 (7-12) weeks. A significant reduction in serum HBV-DNA was achieved at delivery compared with baseline (mean 5.25 ± 1.79 vs. 8.87 ± 0.45 log(10) copies/mL, respectively; p < 0.01). Three had serum ALT levels more than 1.5 times the upper limit of normal and two of these normalized before delivery. The 11 infants were born with no obstetric complication or birth defects. Five infants were breastfed. All infants were hepatitis B surface antigen negative 28-36 weeks after birth. CONCLUSION: Our preliminary data suggest that TDF use in the third trimester is safe, and effectively prevents VT of HBV from high viremic HBeAg-positive mothers.

Electrical inhibition of preterm birth: inhibition of uterine contractility in the rabbit and pup births in the rat.

OBJECTIVE: The purpose of this study was to inhibit uterine contractility during parturition with an electrical current, which is called electrical inhibition, in the rabbit and the rat. STUDY DESIGN: We studied the electrical inhibition of in vitro spontaneously contracting preterm or term gestational rat myometrium tissue and in vivo spontaneously contracting uterus either directly in the rabbit and rat or transvaginally in the rat. Values for myometrial tension, intrauterine pressure, pup birth intervals, and electromyographic activity before and after electrical inhibition were compared. RESULTS: Electrical inhibition decreased rat in vitro myometrial tension by 50%, decreased in vivo rabbit intrauterine pressure by 48%, decreased in vivo rat intrauterine pressure by 80%, and increased birth intervals (latency) by factors of 50 (direct electrical inhibition) and 20 (transvaginal electrical inhibition). All electromyographic activity parameters were reduced significantly. CONCLUSION: Electrical inhibition of the uterus is possible. Electrical inhibition is rapid and localized; the duration can be prolonged, and the reversibility is spontaneous. Electrical inhibition may be a new method of tocolysis in the human.