Chronic pain after childbirth

Neuropathic component of postoperative pain for predicting post-caesarean chronic pain at three months. A prospective observational study

BACKGROUND

Recent investigations have showed that caesarean section (CS) might be a cause of chronic pain, with a consequent decrease in quality of life.

METHODS

Prospective observational study in a Spanish tertiary hospital. Main Outcome measure was to assess early neuropathic characteristics of pain (DN2 score ≥ 3) one week after CS as a potential risk factor for post-caesarean section chronic pain (PCSCP) at three months. Secondary outcome was to identify other risk factors. 610 consecutive consenting patients undergoing CS were interviewed preoperatively, at discharge from recovery room and 24h postoperatively. Telephone follow-up interviews were conducted one week, three months and twelve months following surgery.

RESULTS

We analysed 597 consecutive patients. The incidence of PCSCP at three and twelve postoperative months were 6.2% and 1% respectively. Subjects with NRS score superior to five on movement one week after CS presented higher incidence of PCSCP (NRS superior to five: 19 (52,2%); NRS equal or lower to five: 172 (30,9%); p=0,009). On multivariate analysis neuropathic pain one week after CS was associated with a higher risk of PCSCP (AOR: 1.63 (95% CI: 1.26-2.11; p<0.001). Other identified risk factors for PCSCP were: uterine exteriorization during CS (AOR: 3.89 (95% CI 1.25-12.10; p=0.019) and a lower gestational age (AOR: 0.87 (95% CI: 0.78-0.96; p=0.008).

CONCLUSIONS

Incidence of PCSCP at three and twelve postoperative months was low, 6.2% and 1% respectively. Early neuropathic characteristics of pain after one week measured by neuropathic pain questionnaire, consisting of two questions (DN2) ≥ 3/7 could be used to identify patients at risk for chronic post-surgical pain and develop preventive strategies.

Raising awareness about chronic pain and dyspareunia among women - a Swedish survey 8 months after childbirth

Background and aims Although several studies have been conducted, knowledge about chronic pain and dyspareunia after childbirth is still limited. The aim of this study was to explore the prevalence of chronic pain 8 months after childbirth in a cohort of Swedish women. The characteristics of chronic pain, such as, pain intensity, localization and frequency as well as pain interference with daily activities were examined. An additional aim was to describe the prevalence and intensity of dyspareunia. Methods Data were obtained through two self-administered questionnaires and the patient record system, Obstetrix. The first questionnaire was distributed on the maternity ward, 24-36 h after labour, to Swedish-speaking women who had given birth to a living child (n = 1,507). The second questionnaire was sent by post 8 months after childbirth. We collected data about demographic and social characteristics, pain presence and its onset, as well as pain intensity, frequency, bodily localization and pain interference with activities of women's daily life. Results In total, 1,171 (77.7%) responded to both questionnaires and were included in the analysis. Eight months after giving birth, totally 16.7% (195/1,171) of the women reported chronic pain related to childbirth. Of these, 9.1% (106/1,171) of women reported chronic pain with onset during pregnancy, 4.5% (53/1,171) experienced chronic pain with onset following labour and 3.1% (36/1,171) of women had both chronic pain with onset during pregnancy and chronic pain with onset following labour (each participant could only appear in one of the groups). Women reported a lower prevalence of chronic pain after vaginal delivery than caesarean section (61/916, 6.7% vs. 28/255, 11%, p = 0.021, OR 1.73, 95% CI 1.1-2.8). Moreover, 19.2% (211/1,098) of women experienced dyspareunia. There was no difference regarding prevalence of dyspareunia and the mode of delivery. Of those women who had a vaginal delivery, 19.5% (167/858) experienced pain during intercourse and the corresponding number for women after caesarean section was 18.3% (44/240) (p = 0.694, OR 0.929, CI 0.6-1.3). Approximately 80% of women with chronic pain, and 60% of women that experienced dyspareunia, rated their worst pain as moderate or severe (NRS 4-10). The corresponding number regarding average chronic pain was between 50 and 70%. More than 35% of the women with chronic pain scored pain interference with daily activities as ≥4 on a 0-10 NRS. Conclusions In our study, chronic pain 8 months after childbirth was reported by one in six women and one in five of the women experienced dyspareunia. The intensity of both chronic pain and dyspareunia was reported as moderate to severe in a significant proportion of women and chronic pain interfered considerably with daily activities. Implications There is a need to raise awareness among healthcare providers of this clinical problem as well as to revise and upgrade education regarding pain after childbirth to prevent potential long-term health problems, women's suffering and increased need for health care. The development of strategies for prevention, follow-up and treatment of pain is warranted. More research, including women's experiences of pain as well as intervention studies, are also needed.

Downregulation of microRNA‑29c reduces pain after child delivery by activating the oxytocin‑GABA pathway

A significant decrease in the expression of spinal microRNA-29c (miR-29c), which is responsible for the regulation of oxytocin receptor (OXTR) expression, was observed in nerve injury pain during childbirth. The present study investigates whether spinal miR-29c could be a potential target for the treatment of pain, via the oxytocin (OT)-γ-aminobutyric acid (GABA) pathway. A spared nerve injury (SNI) rat model was established to induce neuropathic pain, simulating hyperalgesia. Spinal neurons were treated with OT to mimic the hormonal changes in the central nervous system after delivery. A change in the neuronal miniature inhibitory postsynaptic currents (mIPSCs) was observed in neurons, following the silencing of miR-29c or OT treatment with or without OXTR antagonist. The Von-Frey apparatus was used to measure the animal behaviors. Molecular biological experiments and electrophysical recordings in vivo and in vitro were performed to reveal the potential analgesic mechanisms. miR-29c was significantly downregulated (more than 8-fold) in the spinal dorsal horn of delivery+SNI rats compared with the SNI rats. The silencing of miR-29c resulted in increased pain threshold in SNI rats. Bioinformatics analysis indicated that OXTR was a potential target gene of miR-29c. The delivery+SNI rats presented with higher levels of OT in the cerebrospinal fluid compared with SNI rats, which indicated that the OT signaling pathway may participate in pain relief response. The increased expression of OXTR and GABA in delivery+SNI rats were observed in the miR-29c-silenced SNI rat model, suggesting that the silencing of miR-29c can mediate pain relief by enhancing the OT-GABA pathway. In addition, an electrophysiology assay was performed to assess the mIPSCs in neurons. The silencing of miR-29c in neurons increased the frequency and amplitude of mIPSCs but there was no influence on the decay time, which suggested that the spinal inhibitory neurons became more active, subsequently reducing the feeling of pain. The inhibition of OXTR reversed the enhanced inhibitory postsynaptic currents, indicating a crucial role for OXTR in the miR-29c-associated pain regulation. Taken together, the results of the present study suggested that spinal oxytocinergic inhibitory control plays an important role in pain relief in the neuropathic pain rat model undergoing vaginal delivery. Silencing spinal miR-29c may be a potential target for pain relief through the OT-GABA pathway.

Opioid-Free Cesarean Section with Bilateral Quadratus Lumborum Catheters

Introduction

Post-operative pain control following cesarean section delivery (CD) is an important topic of discussion given the lack of consensus on a narcotic-sparing analgesic regimen. We describe the case of an elective CD with narcotic-free pain control using continuous bilateral posterior quadratus lumborum (QL) blockade as the primary mode of analgesia.

Case Report

The patient is a 36-year-old female, G3P1, who presented at 37 weeks of gestation in active labor scheduled for elective primary CD. A spinal anesthetic was performed at L4-L5 with hyperbaric 0.75% bupivacaine, without intrathecal morphine. Bilateral posterior QL catheters were placed under sterile conditions with 20 mL of 0.25% bupivacaine per side. Continuous infusion of 0.2% ropivacaine was then started at 10 mL/hour per side. The patient's pain was controlled with QL catheters and a multimodal pain regimen consisting of non-steroidal anti-inflammatory drugs and acetaminophen. The patient reported a resting pain score of 0 with a dynamic pain score of 3 out of 10 throughout her recovery. She was discharged on post-operative (post-op) day 3 and the catheters were removed without any complications.

Discussion

The gold standard for pain control following CD is intrathecal morphine; however, its use has many adverse effects. Bilateral single-shot QL blocks following CD have been proven to decrease opioid consumption but its limited duration has minimal advantage over intrathecal morphine and patients continue to require oral narcotics for analgesia. With the use of QL catheters and a multimodal pain regimen, it may be possible to achieve opioid-free CD for the post-op period.

Persistent pain after cesarean delivery

The incidence of persistent pain after cesarean deliveries (CD) varies but is much lower than after comparable surgeries. However, with over four million deliveries annually and a rising CD rate, even a low prevalence of persistent pain after CD impacts many otherwise healthy young women. Consideration of the pathophysiology of persistent pain after surgery and the risk factors predisposing women to persistent and chronic pain after CD provides insights into the prevention and treatment of persistent pain; and improves the quality of care and recovery after CD. The findings that the peripartum state and oxytocin confer protection against persistent pain may provide new and interesting perspectives for the prevention and treatment of chronic pain caused by trauma or surgery. Predictive tools available to identify and target patients at high risk of acute and chronic pain have mostly weak to modest predictive correlations and many are either not clinically feasible or too time-consuming to apply. Persistent pain has been linked to the severity of acute postoperative pain and opioid exposure. Modified surgical techniques, neuraxial anesthesia and opioid-sparing analgesia may help limit the development of persistent and chronic pain. The goal of this narrative review is to examine the incidence of persistent pain after CD; review briefly the underlying pathophysiology of persistent pain and the transition from acute to chronic pain (with particular emphasis on the uniqueness after CD); and to review modifiable risk factors and prevention strategies that identify at-risk patients and allow tailored treatment.

Chronic pain during pregnancy: a review of the literature

BACKGROUND AND PURPOSE

The majority of the reviews and studies on chronic pain in pregnancy have primarily focused on the pharmacological and non-pharmacological treatment options. The purpose of our review was to identify evidence-based clinical research for the evaluation and management of preexisting chronic pain in pregnancy, chronic pain associated with pregnancy, and chronic pain in relation to mode of delivery.

METHODS

A literature search was undertaken using the search engines PubMed, CINAHL, EBSCOhost, and Web of Science. Search terms used included "chronic pain" AND "pregnant OR pregnancy" OR "pregnancy complications" from inception through August 2016.

RESULTS

The basis of this review was the 144 articles that met inclusion criteria for this review. Based on our review of the current literature, we recommend 7 guidelines for chronic pain management during and after pregnancy: 1) complete history and physical examination; 2) monitor patients for alcohol, nicotine, and substance use; 3) collaborate with patient to set treatment goals; 4) develop a management plan; 5) for opioids, use lowest effective dose; 6) formulate a pain management plan for labor and delivery; and 7) discuss reproductive health with women with chronic pain.

CONCLUSION

The management of chronic pain associated with pregnancy is understudied. Obstetrical providers primarily manage chronic pain during pregnancy. Some general guidelines are provided for those health care providers until more information is available.

Incidence and severity of chronic pain after caesarean section: A systematic review with meta-analysis

BACKGROUND

The frequency of caesarean section has increased dramatically in recent decades. Despite this, robust data regarding the consequences of caesarean section in terms of developing chronic postsurgical pain (CPSP) are still lacking.

OBJECTIVE

This systematic review analysed the incidence and severity of CPSP in women 3 to less than 6, 6 to less than 12, and at least 12 months after caesarean section.

DESIGN

Systematic review of prospective and retrospective observational studies and randomised controlled trials with meta-analysis.

DATA SOURCE

We searched MEDLINE to May 2015.

ELIGIBILITY CRITERIA

We included all studies investigating the incidence and/or severity of CPSP at least 3 months after caesarean section. The primary outcome was chronic postsurgical wound pain (CPSP 'wound'). Secondary outcomes were persistent pain in the back area, pelvic region or reported as residual pain, and severity of 'birth-related' chronic pain.

RESULTS

Meta-analysis using the random-effects model based on 15 studies (n = 4475) reporting CPSP 'wound' at 3 to less than 6 months after caesarean section revealed an incidence of 15.4% [95% confidence interval (CI): 9.9 to 20.9%]. For 6 to less than 12 and at least 12 months after caesarean section, the incidence of CPSP 'wound' was estimated at 11.5% (95% CI: 8.1 to 15.0%, n = 3345) and 11.2% (95% CI: 7.4 to 15.0%, n = 3451), respectively. Meta-regression analysis using the publication year as predictor revealed stable CPSP 'wound' incidences at each postoperative time slot from 2002 to the present. Of those patients who reported chronic pain, 9.6% (95% CI: 0.0 to 21.0%) had severe pain, 23.5% (95% CI: 10.0 to 37.0%) had moderate pain and 49.2% (95% CI: 18.9 to 79.4%) had mild pain at 6 months.

LIMITATIONS

Major limitations are high statistical heterogeneity of the meta-analyses and inconsistencies in reporting severity of chronic 'birth-related' pain.

CONCLUSION

This meta-analysis finds a clinically relevant incidence of CPSP 'wound' after caesarean section ranging from 15% at 3 months to 11% at 12 months or longer that has been largely stable in recent years.

Prevalence and Predictors of Chronic Pain in Pregnancy and Postpartum

OBJECTIVE

A clinically relevant number of patients report pain 1 year after vaginal delivery or Caesarean delivery. Study objectives were to identify the incidence of peripartum pain; determine whether pre-existing pain, pregnancy pain, or pain 2 weeks postpartum predicts pain at 3 months; and to identify whether delivery mode, epidural analgesia use, or delivery complications predict non-genito-pelvic pain postpartum.

METHODS

Primiparous women at 30 to 36 weeks GA with an uncomplicated singleton pregnancy were recruited from a large perinatal clinic. Participants completed questionnaires on sociodemographics and non-genito-pelvic pain. Questionnaires were completed in the perinatal clinic and then electronically 2 weeks and 3 months postpartum.

RESULTS

Of the 133 women included, 50 patients (38%) had a chronic pain condition or pain prior to pregnancy, whereas 73 patients (55%) reported pain in pregnancy. Pain was present 2 weeks postpartum in 57 patients (43%) and 3 months postpartum in 33 patients (25%). Patients with pre-existing pain were more likely to experience pain 2 weeks postpartum (P = 0.006), and patients with pain 2 weeks postpartum were more likely to have pain 3 months postpartum (P = 0.005). Women who had a Caesarean delivery (P < 0.001) were more likely to have non-genito-pelvic pain at 2 weeks but not 3 months postpartum.

CONCLUSIONS

Women with pain 2 weeks postpartum were significantly more likely to have pain at 3 months. Further investigation is required to determine whether pre-existing pain, pain in pregnancy, or pain at 2 weeks postpartum can adequately predict the likelihood of chronic pain.

Pharmacogenetics in obstetric anesthesia

The 21st century has been billed as the era of "precision/personalized medicine." Genetic investigation of clinical syndromes may guide therapy as well as reveal previously unknown biological or pharmacological pathways that may result in novel drug therapies. Several clinical issues in obstetrics and obstetric anesthesiology have been targets for genetic investigations. These include evaluation of the genetic effects on preterm labor and the progression of labor, spinal anesthesia-induced hypotension and the response to medications used to treat hypotension, and the effect of gene variants on pain and analgesic responses. Most studies have examined specific single nucleotide polymorphisms. Findings have revealed modest effects of genetic variation without tangible impact on current clinical practice. Over the next decade, increased availability of whole exome and genome sequencing, epigenetics, large genetic databases, computational biology and other information technology, and more rapid methods of real-time genotyping may increase the impact of genetics in the clinical arena of obstetrics and obstetric anesthesia.

Implications of pain in functional activities in immediate postpartum period according to the mode of delivery and parity: an observational study

OBJECTIVES

To identify women's complaints about pain in the immediate postpartum of vaginal delivery and cesarean section; to measure the intensity of pain in postpartum women at rest and with selected movements and to compare the activity limitations in relation to the mode of delivery and parity.

METHOD

Observational, descriptive, cross-sectional study. Eighty-six women, in the immediate postpartum period after vaginal delivery (n=43) and cesarean section (n=43), were evaluated for physical discomforts and their difficulty in performing functional activities.

RESULTS

Abdominal pain (mean differences=-39.5%; 95% CI=-57.3 to -21.8%), neck pain (mean differences=-16.3%; 95% CI=-32.3 to -0.3%) and edema (mean differences=-41.4%; 95% CI=-63.3 to -20.4%) were reported of cesarean women postpartum. Perineal pain (p<0.05) was reported in vaginal delivery women postpartum. Postpartum pain was more severe during movement after cesarean section (p<0.05) resulting in pain during the activities of sitting down (mean differences=-30.2%; 95% CI=-50.7 to -9.8%), standing up from a sitting position (mean differences=-46.5%; 95% CI=-65.0 to -28.0%), walking (mean differences=-44.2%; 95% CI=-65.2 to -23.1%), lying down (mean differences=-32.6%; 95% CI=-54.9 to -10.3%) and taking a bath (mean differences=-24.0%; 95% CI=-43.1 to -5.0%). Correspondence analysis found no association between parity and functional limitations.

CONCLUSION

The highest number of complaints was associated with movement activities and cesarean section postpartum. There was no relationship between functional limitations and parity in this study.

Pelvic pain after childbirth: a longitudinal population study

In this longitudinal population study, the aims were to study associations of mode of delivery with new onset of pelvic pain and changes in pelvic pain scores up to 7 to 18 months after childbirth. We included 20,248 participants enrolled in the Norwegian Mother and Child Cohort Study (1999-2008) without preexisting pelvic pain in pregnancy. Data were obtained by 4 self-administered questionnaires and linked to the Medical Birth Registry of Norway. A total of 4.5% of the women reported new onset of pelvic pain 0 to 3 months postpartum. Compared to unassisted vaginal delivery, operative vaginal delivery was associated with increased odds of pelvic pain (adjusted odds ratio [OR]: 1.30; 95% confidence interval [CI]: 1.06-1.59). Planned and emergency cesarean deliveries were associated with reduced odds of pelvic pain (adjusted OR: 0.48; 95% CI: 0.31-0.74 and adjusted OR: 0.65; 95% CI: 0.49-0.87, respectively). Planned cesarean delivery, young maternal age, and low Symptom Checklist-8 scores were associated with low pelvic pain scores after childbirth. A history of pain was the only factor associated with increased pelvic pain scores over time (P = 0.047). We conclude that new onset of pelvic pain after childbirth was not commonly reported, particularly following cesarean delivery. Overall, pelvic pain scores were rather low at all time points and women with a history of pain reported increased pelvic pain scores over time. Hence, clinicians should follow up women with pelvic pain after a difficult childbirth experience, particularly if they have a history of pain.

Development of chronic pain after episiotomy

OBJECTIVE

To analyze the incidence of chronic pain 5 months after episiotomy, as well as potential prognostic factors.

METHODS

A prospective cohort observational study was conducted on pregnant women age≥18 years who had undergone an episiotomy. The presence of pain was evaluated in the area of episiotomy at 24 and 48 h of delivery using a structured face-to-face questionnaire, and by telephone questionnaire at 5 months. The primary endpoint was the presence of persistent pain at 5 months. A record was made of the presence of pain at delivery, and its intensity, the presence or absence of epidural analgesia, instrumental delivery, perineal tear, and pain when episiotomy was performed, as well as the presence of dyspareunia and urinary incontinence at 5 months post-episiotomy.

RESULTS

A total of 87 parturient patients were included, of whom 78 completed the study. Of the patients who completed the study, 12.8% reported chronic episiotomy pain. Epidural analgesia was associated with a higher incidence of instrumental delivery and less pain at the time of episiotomy and expulsion (P<.0005, P<.02, and P<.01, respectively). Chronic pain is associated with operative delivery (P<.017), and with the presence of pain at rest at 24 and 48 h (P<.01), of wound complications (P<.026), and of dyspareunia (P<.001).

CONCLUSION

An incidence of 12.8% of women developing chronic pain after delivery with episiotomy suggests a health problem. More studies are needed to confirm our results.

Axotomy of tributaries of the pelvic and pudendal nerves induces changes in the neurochemistry of mouse dorsal root ganglion neurons and the spinal cord

Using immunohistochemical techniques, we characterized changes in the expression of several neurochemical markers in lumbar 4-sacral 2 (L4-S2) dorsal root ganglion (DRG) neuron profiles (NPs) and the spinal cord of BALB/c mice after axotomy of the L6 and S1 spinal nerves, major tributaries of the pelvic (targeting pelvic visceral organs) and pudendal (targeting perineum and genitalia) nerves. Sham animals were included. Expression of cyclic AMP-dependent transcription factor 3 (ATF3), calcitonin gene-related peptide (CGRP), transient receptor potential cation channel subfamily V, member 1 (TRPV1), tyrosine hydroxylase (TH) and vesicular glutamate transporters (VGLUT) types 1 and -2 was analysed seven days after injury. L6-S1 axotomy induced dramatic de novo expression of ATF3 in many L6-S1 DRG NPs, and parallel significant downregulations in the percentage of CGRP-, TRPV1-, TH- and VGLUT2-immunoreactive (IR) DRG NPs, as compared to their expression in uninjured DRGs (contralateral L6-S1-AXO; sham mice); VGLUT1 expression remained unaltered. Sham L6-S1 DRGs only showed a small ipsilateral increase in ATF3-IR NPs (other markers were unchanged). L6-S1-AXO induced de novo expression of ATF3 in several lumbosacral spinal cord motoneurons and parasympathetic preganglionic neurons; in sham mice the effect was limited to a few motoneurons. Finally, a moderate decrease in CGRP- and TRPV1-like-immunoreactivities was observed in the ipsilateral superficial dorsal horn neuropil. In conclusion, injury of a mixed visceral/non-visceral nerve leads to considerable neurochemical alterations in DRGs matched, to some extent, in the spinal cord. Changes in these and potentially other nociception-related molecules could contribute to pain due to injury of nerves in the abdominopelvic cavity.

Breastfeeding and pelvic girdle pain: a follow-up study of 10,603 women 18 months after delivery

OBJECTIVE

To study the associations of patterns and duration of breastfeeding with the persistence of pelvic girdle pain 18 months after delivery.

DESIGN

Longitudinal population study.

SETTING

Norway, for the period 1999-2011.

POPULATION

A follow-up of 10 603 women with singleton deliveries in the Norwegian Mother and Child Cohort Study who reported pelvic girdle pain at 0-3 months postpartum.

METHODS

Data were obtained by four self-administered questionnaires and linked to the Medical Birth Registry of Norway.

MAIN OUTCOME MEASURE

Pelvic girdle pain, defined as combined anterior and bilateral posterior pelvic pain, 18 months after delivery.

RESULTS

Eighteen months after delivery, 7.8% of respondents (829/10,603) reported pelvic girdle pain. Breastfeeding patterns at 5 months after delivery were not associated with persistence of pelvic girdle pain. The proportion of women with pelvic girdle pain 18 months after delivery increased as the duration of breastfeeding decreased (test for trend, P < 0.001). The estimated associations attenuated after adjustment for educational level, smoking status, and body mass index, but remained statistically significant for the association between 0 and 2 months of breastfeeding and persistent pelvic girdle pain (adjusted odds ratio 1.34; 95% confidence interval 1.03-1.75). The association of short breastfeeding duration with persistent pelvic girdle pain was only present in women with body mass index ≥25 kg/m(2) .

CONCLUSIONS

Breastfeeding was associated with a small beneficial effect on the recovery process of pelvic girdle pain in women with a body mass index ≥25 kg/m(2) . Among women with pelvic girdle pain, breastfeeding should be encouraged in accordance with the existing child-feeding recommendations.