Inhibitory effects of electrical stimulation on delivery in pregnant rats

Sacral Neuromodulation in Pregnant Women—A Case Report and Literature Review

Millions of women around the world suffer from an overactive bladder and urinary retention. A significant number of them are of reproductive age. For 25 years, SNM has been an effective therapy for treatment-resistant hyperactive bladder and idiopathic urinary retention. The paper presents a case of a 35-year-old pregnant woman with an overactive bladder resistant to pharmacological treatment, who responded positively to sacral neuromodulation. The patient decided against deactivating the neuromodulator and, after an uneventful course of pregnancy, she gave birth by a caesarean section to a healthy female infant. The use of SNM in pregnant patients remains a constant clinical challenge. The current literature was reviewed, but published studies do not provide a clear answer. Further studies with a long follow-up period are necessary to determine more accurately the effects of SNM therapy on the fetus and the course of pregnancy. Currently, it is recommended to deactivate SNM during pregnancy. However, it seems that an individual approach to the patient with information on the risks and benefits of continuing or discontinuing therapy should be the current procedure.

Non-Invasive Ring Electrode With a Wireless Electrical Recording and Stimulating System for Monitoring Preterm Labor

Preterm labor and birth are the primary causes of neonatal morbidities and mortalities. The early detection and treatment of preterm uterine muscular contraction are crucial for the management of preterm labor. In this work, a ring electrode with a wireless electrical recording and stimulating (RE-WERS) system was designed, fabricated, and investigated for the non-invasive monitoring of uterine contraction/relaxation as a diagnostic and therapeutic tool for preterm labor. By using an organ bath system, we confirmed that the uterine contraction force in mice can be decreased by the application of electrical stimulation. Then, the RE-WERS system was inserted non-invasively through the vagina to the cervix of a pregnant minipig, and it successfully recorded the uterine contraction and reflect signals when various electrical stimulating conditions were applied. The difference in the uterine signals before and after the injection of a labor induction drug, such as oxytocin and prostaglandin [Formula: see text], was recorded, and the difference was remarkable. In addition, the uterine signal that was recorded was well matched with the signal of the electromyography (EMG) kit during open abdominal surgery. It seemed that the continuous and various electrical stimulations affected the delay or inhibition of childbirth in the pregnant minipig.

Uterosacral Nerve Stimulation via Cuff Electrode: A Preliminary Animal Study for Potential Application to Treatment of Preterm Labor

Preterm labor occurs in about 12% of all pregnancies, accounting for at least 75% of neonatal deaths. The neonatal outcomes depend on mainly the gestational age at delivery. The lower the gestational age, the higher the risk of morbidity and mortality. The management of preterm labor involves early detection of high-risk women, prevention and treatment. In this study, the feasibility and stability of implantable cuff electrodes detection and inhibition of uterine contractions for preterm labor treatment were investigated by in-vivo mouse test. In order to check functionality of implanted electrodes, acute in-vivo test at mouse uterosacral ligament was performed by using cuff electrode which stimulate and record nerve activity. As results, the electrical stimulation via a stimulating cuff electrode at mouse uterosacral ligament was properly applied and nerve fiber's signal was recorded via the recording electrode. In addition, the implanted cuff electrodes could obtain stable recording signal to the periodic electrical stimulation for 7 weeks.

Sacral neuromodulation and pregnancy: Results of a national survey carried out for the neuro-urology committee of the French Association of Urology (AFU)

AIMS

To assess the impact of sacral neuromodulation (SNM) on pregnancy and vice-versa, by identifying women who had received SNM for lower-urinary tract symptoms (LUTS) and had become pregnant.

METHODS

A cross-sectional descriptive study was carried out based on responses to an on-line questionnaire sent to practitioners listed on the InterStim enCaptureTM National Registry. Questions were related to pre-pregnancy health and SNM efficacy, deactivation of the device, its impact on LUTS, childbirth, the infant, its reactivation and postpartum effectiveness.

RESULTS

Twenty-seven pregnancies were recorded among 21 women. Six women had had a pregnancy prior to implantation, two of whom had had a c-section. A total of 18.5% of women had the device disabled prior to conception. The others had their device disabled during the first trimester and did not reactivate it before delivery. Complications were reported in 25.9% of pregnancies: six women had urinary infections, including three of the four treated for chronic retention of urine (CRU), and 1 woman had pain at the stimulation site. There were 24 live births (including one premature birth and four c-sections), one spontaneous miscarriage and two voluntary interruptions of pregnancy. No neonatal disorders have been reported. Effectiveness of sacral neuromodulation decreased in 20% in postpartum.

CONCLUSIONS

In 27 pregnancies established during SNM for LUTS, 18.5% of patients deactivated their case before pregnancy and the others switched it off during the first trimester. Three-quarters of women with CRU had urinary infection. No adverse effects on fetuses were found. SNM effectiveness deteriorated in 20% cases after childbirth.

The effect of bilateral pelvic neurectomy on uterine and abdominal electrical and pressure activity, as measured by telemetry in conscious, unrestrained pregnant rats

AIMS

Bilateral pelvic neurectomy (BPN) interferes with delivery in rats. This work measures the effect of BPN on uterine and abdominal electromyography (EMG) and pressure during gestation and delivery.

METHODS

Uterine EMG and intra-uterine pressure (IUP), as well as abdominal muscle EMG and intra-abdominal pressure (IAP), were recorded on days 19-24 in rats. Mean values were determined for the peak frequency of the power density spectrum (PDS) of the uterine and abdominal EMG "bursts," the integral of the abdominal EMG power spectrum (IPS), and the area under the IUP and IAP curves (AUIUP and AUIAP).

RESULTS

Uterine EMG power density spectrum peak frequency and AUIUP were low during days 19-21 in all rats, and on days 22-23 increased sharply and significantly in both groups. Before delivery, sham rat recordings showed sudden sharp increases in AUIAP, AUIUP and IPS as "pushing" was observed. Pushing was not observed or recorded in laboring BPN rats and they did not deliver normally.

CONCLUSIONS

A functional pelvic nerve is required for normal labor and delivery in rats. BPN inhibits abdominal EMG and contractions necessary to expel the fetus.