This study aimed to investigate the effect of epidural analgesia on the incidence of postpartum depression. A prospective study was conducted including 229 primiparous women who delivered vaginally at term with a single fetus. Participants were randomized into two groups: a control group (116 cases) and a study group (113 cases) based on whether they chose to receive epidural analgesia. The incidence of postpartum depression in the study group was lower than that in the control group (14.2% vs. 29.3%), and the difference was statistically significant (P=0.006). There were no significant differences between the two groups in terms of breastfeeding rate or EPDS scores at 42 days postpartum (P > 0.05). Single-factor analysis of postpartum depression showed that 19 factors, including gestational weeks, fetal suction, HB, internal medicine diseases, income less than 10,000 yuan, dissatisfaction with housing, history of surgery, labor analgesia, not attending antenatal classes, premenstrual syndrome, pre-delivery SDS score, neonatal asphyxia, EMS score at 3 days postpartum, EPDS score at 3 days postpartum, breastfeeding rate at 3 days postpartum, neonatal hospitalization, comfort satisfaction, EPDS score at 42 days postpartum, and breastfeeding rate at 42 days postpartum, were significantly associated with the occurrence of postpartum depression between the two groups (P < 0.05). Multivariate logistic regression analysis of postpartum depression showed that epidural analgesia was an independent protective factor, while neonatal hospitalization after birth and general comfort satisfaction were two risk factors. The use of epidural analgesia during labor can effectively improve the quality of obstetrics and reduce the risk of postpartum depression, and is worthy of promotion and application.

• Epidural Labor Analgesia

• Peripartum

• Postpartum

Bao Q, Qian Q, Pan W, Liu L, Zhou Z, et al. (2024) The Effect of Epidural Labour Analgesia on the Development of Postpartum Depression: A Prospective Cohort Study. Med J Obstet Gynecol 12(2): 1186

Postpartum depression (PPD) is a severe form of depression during the postpartum period and is a common type of mental disorder. 15% to 85% of women develop PPD within 4-6 weeks [1,2], which is characterized by feelings of low mood and a range of symptoms such as mild mania, irritability, crying, fatigue, confusion, decreased appetite, lack of positive emotions, loss of pleasure, insomnia, and others [3,4]. PPD increases the risk of various negative consequences for children, women, and families, including poor infant physical health and more frequent illnesses, as well as physiological and psychological stress, and delays in the infant and toddler’s mental, emotional, and psychomotor development [5]. The incidence of PPD is about 30% in foreign countries, and it is more likely to occur in introverted and conservative women. In Chinese postpartum women, the incidence rate ranges from 6.5% to 29.5% [6-9]. Foreign studies have suggested that severe pain during delivery [10-12], and lack of sufficient care and support can increase the risk of PPD. The use of epidural labor analgesia is associated with a reduced risk of PPD [10,12,13], and epidural analgesia can effectively alleviate labor pain. The study by Ding et al. [10], showed that the incidence of PPD was 34.6%, while the use of epidural analgesia reduced the incidence of PPD to 14.0%. This suggests that the effective use of epidural analgesia can reduce the incidence of PPD. Our obstetrics department has responded positively to the notice on conducting pilot work for labor analgesia issued by the National Health Commission in November 2018, and has implemented epidural anesthesia for labor analgesia. This paper aims to prospectively evaluate the safety of epidural labor analgesia during the peripartum period and its impact on the occurrence of PPD, and to explore the related factors affecting the incidence of PPD. This will guide us in providing better health care for pregnant and postpartum women, and provide clinical evidence for the development of effective health education and promotion interventions in the future. The authors have analyzed the impact of epidural anesthesia on the risk of PPD and the factors contributing to the occurrence of PPD, and the results are reported below.

The research plan was approved by the Medical Ethics Committee of our hospital

All the primiparous women participating in this study were voluntary and signed written informed consent. Depression assessment was conducted during the antenatal period. Relevant data from 229 primiparous women who underwent natural vaginal delivery at term in the obstetric ward of ∗∗∗ from October 2019 to September 2021 were collected. The age of the primiparous women ranged from 15 to 37 years, and the gestational weeks at delivery ranged from 260 to 290 days. They had no obstetric complications, no history of depression, mental illness, personality disorders, or brain diseases, and were excluded from epidural anesthesia contraindications. Zung’s Self-Rating Depression Scale was used for depression screening before delivery, and only those with scores <50[14], were included. Participants were divided into two groups according to the principle of subjective voluntariness: the natural delivery group without any analgesia techniques as the control group (n=116) and the epidural anesthesia group as the study group (n=113). The researchers did not exert any external interference. In case of maternal and fetal life-threatening conditions or strong demands from pregnant women during labor, cesarean section was performed.

During the study period, a total of 246 primiparous women who met the inclusion criteria were included in the prospective study after screening.

Among them, 10 women in the control group and 7 women in the study group lost follow-up at 42 days postpartum. Finally, 229 women were included in the final analysis. After admission, routine auxiliary examinations were performed to exclude fetal- maternal disproportion, and a general survey questionnaire and Zung’s Self-Rating Depression Scale were completed. The study group underwent epidural anesthesia for labor pain relief after regular uterine contractions and cervical dilatation of 2-3 cm. Epidural anesthesia was performed by an anesthesiologist at the L2, 3 or L3, 4 interspace, and ropivacaine 8-10ml and sufentanil 30 μg were injected into the subarachnoid space after successful puncture. After ensuring satisfactory anesthesia, the epidural catheter was connected to a PCA pump and infused at a rate of 10-12 ml/h, with additional doses of anesthetics given according to the maternal pain score. The catheter was removed after full cervical dilatation (10 cm) and the cessation of the PCA pump. For the control group, routine intrapartum monitoring and delivery guidance were provided by midwives.

After entering the delivery room, intravenous lactated Ringer’s solution was administered through an open vein, and routine electrocardiographic monitoring was performed. A midwife was assigned as a guide to provide emotional support, teach breathing techniques, and relaxation skills during labor. Psychological counseling was provided to alleviate fear and anxiety, and postpartum health care knowledge was taught. The team members responsible for the specific operations of the study received detailed training, and all participants were organized into a WeChat group (the most commonly used social software in China). The Edinburgh Postnatal Depression Scale (EPDS) and Enrich Marriage Scale (EMS) were completed by both groups of subjects 3 days after delivery (before discharge) and 42 days after delivery (at the physical examination), or via WeChat if patients were unable to return to the hospital. If patients scored above the cutoff value of 13 points on the EPDS, they were referred to a psychiatric clinic for further evaluation and treatment.

Observation Indicators

? Zung Self-Rating Depression Scale (SDS) score: Developed by W.K. Zung in 1965, SDS is currently the most commonly used self-rating depression scale in the field of psychiatry.

? Edinburgh Postnatal Depression Scale (EPDS) score: Developed by Cox et al. in 1987, EPDS is used in this study with a cut-off score of 10 for screening.

? Enrinch Marriage Scale: Consisting of 124 items, each rated on a 5-point scale, the sum of all scores is the total score, with higher scores indicating better marital quality.

Statistical analysis

Continuous variables were expressed as mean ± standard deviation (SD) or median (range). Data were compared using independent samples t-test or Mann-Whitney U test. Non- normally distributed metric data were expressed as median (interquartile range), and between-group comparisons were performed using rank sum test. Categorical variables were expressed as the number of patients (percentage). Data were analyzed using the chi-square test or Fisher’s exact test. The chi- square test was used for univariate analysis, and the relationship between the use of epidural labor analgesia and PPD was evaluated using multiple logistic regression analysis. Differences with P<0.05 were considered statistically significant.

Statistically significant differences (P<0.05) between the study group and the control group

There were statistically significant differences (P<0.05) between the study group and the control group in terms of internal medical diseases, education years, and planned pregnancy, while there were no significant differences in other general conditions and prenatal SDS scores (P>0.05). None of the enrolled subjects had depression (SDS<50) before delivery (Table 1).

Table 1: Comparison of baseline characteristics between two groups of pregnant women.

Comparison of labor and neonatal outcomes between the two groups

There were statistically significant differences (P<0.05) between the study and control groups in the progress of the first and second stages of labor, but no statistically significant differences (P>0.05) were observed in the third stage of labor. There were no statistically significant differences (P>0.05) in neonatal information, including gender, birth weight, and the use of fetal suction during delivery, between the two groups. However, there was a statistically significant difference (P<0.05) in the incidence of neonatal asphyxia between the groups (Table 2).

Table 2: Comparison of maternal and neonatal outcomes between two groups during delivery

Comparison of study indices in the two groups of postpartum women three days after delivery

There was no significant difference in the rate of breastfeeding between the two groups of postpartum women on the third day after delivery (P>0.05), nor in the EPDS score (P>0.05) or EMS marital satisfaction score (P>0.05). There was also no significant difference in the hospitalization rate of newborns between the two groups (P>0.05). However, the satisfaction level of the entire delivery process among the women in the study group was significantly higher than that in the control group, with a statistical significance of P<0.001 (Table 3).

Table 3: Comparison of postpartum indicators between the two groups after three days of delivery

Comparison of postpartum 42-day study indicators between the two groups of mothers

In the comparison of postpartum 42-day study indicators between the two groups of mothers, among a total of 229 mothers, 50 cases (21.8%) (34 in the control group and 16 in the study group) were diagnosed with postpartum depression with EPDS score ≥10 points. The incidence of postpartum depression in the study group was significantly lower than that in the control group (14.2% vs. 29.3%, P=0.006). The difference was statistically significant. The difference in the rate of exclusive breastfeeding between the two groups was statistically significant (P<0.001) (Table 4).

Table 4: Comparison of study indicators for postpartum mothers in the two groups at 42 days after delivery

Univariate analysis of postpartum depression incidence at 42 days

When postpartum depression at 42 days was taken as the dependent variable, the univariate analysis showed that there were 19 significant factors among all the recorded variables of mothers and newborns, which were significantly different between the two groups and were related to the occurrence of postpartum depression, with statistically significant differences (P<0.05) (Table 5).

Table 5: Univariate analysis of postpartum depression at 42 days after delivery in primiparous women.

Multiple-factor logistic regression analysis

A multiple-factor logistic regression analysis was performed on the occurrence of postpartum depression in two groups of mothers at 42 days postpartum. The dependent variable was the occurrence of postpartum depression, and 19 statistically significant parameters from the univariate analysis were used as independent variables. The results showed that within the 95% confidence interval, the odds ratio (OR) was <1, indicating that the use of labor analgesia was an independent protective factor against postpartum depression. There were also two risk factors (OR > 1) identified: neonatal hospitalization after birth and lower comfort satisfaction (fair/good) which had statistically significant differences (Table 6).

Table 6: Multivariate logistic regression analysis of factors associated with postpartum depression in the two groups of mothers at 42 days after delivery.

Pregnancy and childbirth are processes that the majority of women must experience in their lifetime. When faced with the social role transition, women may experience psychological stress and anxiety due to fear of intense pain during labor, lack of knowledge about the birthing process, concern about the gender of the newborn and the expectations of family members, and inadequate support from family and society. These factors can lead to emotional disorders after childbirth in women, including the occurrence of depression. Severe pain during labor, which has been considered a normal part of childbirth and often overlooked, has not been thoroughly studied in relation to the development of postpartum depression. In recent years, the incidence of postpartum depression has gradually increased, which not only affects the physical and mental health of the mother but also affects the physical and mental health of the baby and the stability of the family. Therefore, it is necessary to focus on the impact of labor analgesia on the incidence of postpartum depression and explore new research approaches that encompass psychological, biological, and sociological factors for postpartum depression.

Analysis of the incidence of postpartum depression in two groups

Postpartum depression occurring within 42 days after delivery (puerperium) is defined as postpartum depression. The peak incidence of postpartum depression occurs on the 5th day after delivery. The Edinburgh Postnatal Depression Scale (EPDS) was used to evaluate the specificity and sensitivity of postpartum depression at 3 days and 42 days after delivery, respectively, which are both relatively high. Therefore, this study evaluated the depression status of mothers at 3 days and 42 days after delivery. Previous studies have reported that the severity of delivery pain is associated with the risk of postpartum emotional disorders or depression [15,16]. The results of this study suggest that the use of epidural analgesia during delivery can reduce the incidence of postpartum depression. Ding et al.’s study [10], showed that the incidence of postpartum depression was 34.6%, while the use of delivery analgesia can reduce the incidence of postpartum depression to about 14%. In this study, the incidence of postpartum depression in the study group was 14.2%, while the incidence in the control group was 29.3%, which is consistent with the above research results. The results of this study suggest that the use of epidural analgesia during delivery can reduce the incidence of postpartum depression, which is consistent with existing literature [15,16].

The Edinburgh Depression Scale (EPDS) used in this study has been well validated in Chinese mothers [17]. The EPDS was originally designed to identify postpartum depression disorders [18,19]. In Western countries, a cut-off score of 12 or 13 is often used to screen for postpartum depression, while the international standard score of 10 is used for classification [18]. Scores equal to or greater than 10 are considered depressed, while scores less than 10 cannot be classified as depression.

Postpartum Depression

According to existing research results, postpartum depression (PPD) is thought to be caused by multiple psychological, biological, and social factors acting independently or in combination [4]. A single-factor analysis of PPD occurrence in postpartum women at 42 days in this study revealed that there were 19 significant factors (Table 5), with statistically significant differences (P<0.05) between the two groups, which were correlated with PPD occurrence. These factors were gestational weeks, fetal suction, hemoglobin level, comorbid internal medical diseases, income less than 10,000 yuan, dissatisfaction with housing, previous surgery history, labor analgesia, non-attendance at antenatal classes, premenstrual syndrome, prenatal SDS score, neonatal asphyxia, postpartum 3-day EMS score, postpartum 3-day EPDS score, postpartum 3-day breastfeeding rate, neonatal hospitalization, comfort satisfaction, postpartum 42-day EPDS score, and postpartum 42-day breastfeeding rate. The results of this study suggest that there is a certain correlation between the depression score on postpartum day 3 and the occurrence of PPD, which confirms the conclusions of previous studies [10]. We found that when women developed PPD (EPDS score ≥10) at 42 days postpartum, their EPDS scores on day 3 postpartum were also high. This means that a high EPDS score on day 3 postpartum can increase the incidence of PPD. Therefore, we propose that a series of support and intervention measures should be taken early for women with high EPDS scores on day 3 postpartum to deepen the study of PPD. We hope to use relevant medical, psychological, and sociological knowledge to care for and protect women during the childbirth process, which may reduce the risk of women with high EPDS scores on day 3 postpartum developing PPD.

Currently, antenatal classes provide pregnant women with a lot of professional knowledge about pregnancy, delivery, and postpartum maternal and child health, which effectively helps them prepare for childbirth psychologically and relieve their anxiety and concerns about the perinatal period. Therefore, many people believe that attendance rates at antenatal classes can also reduce the risk of PPD [10]. However, in this study, there was no correlation between attendance rates at antenatal classes and PPD. The relationship between breastfeeding and maternal depression has been reported in many studies. Breast milk is the ideal food for infant growth, and breastfeeding can enhance the mother-infant relationship. Early breastfeeding mothers have significantly higher levels of prolactin in their circulation than artificially fed or mixed-fed mothers, which is related to less anxiety and depression in the early postpartum period [20].

Additionally, numerous studies have shown that social support is considered a crucial factor closely related to postpartum depression, with the spousal relationship playing a crucial role in the support system [18,21]. Our study revealed that individuals with poor marital relationships (low marital satisfaction and low EMS scores) had a higher incidence of postpartum depression. Similar reports have also been observed in other countries, where women with postpartum depression complain of inadequate support from various sources. Support from all aspects of the support system can encourage women to bravely face physical, psychological discomfort, and fear during pregnancy, childbirth, and postpartum, which has a significant impact on the occurrence of postpartum depression.

Multiple Factors Logistic Regression Analysis of Postpartum Depression

Our research results show that, further logistic regression analysis was conducted for the 19 parameters that were statistically significant in the results of the one-way analysis, and 16 single factors were excluded after testing for multiple covariance. Epidural analgesia during childbirth (regression coefficient B=-1.261, P=0.012, [OR] 0.674, 95% CI, 0.301-2.16) was found to be an independent protective factor against postpartum depression in the multiple logistic regression analysis with OR value <1 within the 95% CI range. Additionally, two risk factors (OR values >1) were identified: general comfort satisfaction and infant hospitalization after birth.

As a hallmark of civilized obstetrics, reducing and eliminating labor pain and relieving the anxiety and tension during pregnancy and childbirth have become one of the important measures to improve obstetric quality, given the current lack of clinical and basic research on the correlation between labor pain and postpartum depression. People hope to reduce the incidence of postpartum depression through psychological, biological intervention, and various social support. The rate of labor analgesia in foreign countries is over 80%, but currently, the rate in China is less than 1%. Whether further research can be carried out to improve the relevant content of labor analgesia is an important indicator of the progress of obstetrics civilization, an important content of perinatal health care, and one of the important ways to reduce the incidence of postpartum depression.

Therefore, it is necessary to fully understand the associations of various factors related to postpartum depression, and to conduct multi-angle and comprehensive research on the intrinsic relationship between the risk factors of postpartum depression to effectively prevent and intervene as necessary, which can lower the incidence of postpartum depression [4]. In summary, the use of epidural anesthesia effectively improves obstetric quality, enhances maternal comfort and satisfaction, greatly reduces the occurrence of postpartum depression, and increases the willingness of mothers to conceive and give birth again. Therefore, it is worthy of promotion and application.

All procedures performed in this study involving human participants were in accordance with the ethical standards of the institutional research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards.

Informed Consent

Informed consent was taken by all participants and anonymity of the answers were ensured.

1. Kim S, Soeken TA, Cromer SJ, Martinez SR, Hardy LR, Strathearn L, et al. Oxytocin and postpartum depression: delivering on what’s known and what’s not. Brain Res. 2014; 1580: 219-232.
2. Meltzer Brody S, Howard LM, Bergink V, Vigod S, Jones I, Munk Olsen T, et al. Postpartum psychiatric disorders. Nat Rev Dis Primers. 2018; 4: 18023.
3. Schiller CE, Meltzer-Brody S, Rubinow DR. The role of reproductive hormones in postpartum depression. CNS Spectr, 2015; 20: 48-59.
4. Stewart DE, Vigod S. Postpartum Depression. N Engl J Med. 2016; 375: 2177-2186.
5. Van den Bergh BR, Mulder EJ, Mennes M Glover V. Antenatal maternal anxiety and stress and the neurobehavioural development of the fetus and child: links and possible mechanisms. A review. Neurosci Biobehav Rev. 2005; 29: 237-258.
6. Armony-Sivan R, Shao J, Li M, Zhao Z, Xu G, Zhou M, et al. No relationship between maternal iron status and postpartum depression in two samples in China. J Pregnancy. 2012; 521431.
7. Howard LM, Molyneaux E, Dennis CL, Rochat T, Stein A, Milogrom J. Non-psychotic mental disorders in the perinatal period. Lancet. 2014; 384: 1775-1788.
8. QiW, Zhao F, Liu Y, Li Q, Hu J. Psychosocial risk factors for postpartum depression in Chinese women: a meta-analysis. BMC Pregnancy Childbirth. 2021; 21: 174.
9. Xiong J, Fang Q, Huang L, Yan X, Zheng X. Group-Based Trajectory Analysis for Postpartum Depression Symptoms among Chinese Primiparous Women. J Clin Med. 2021; 11.
10. Ding T, Wang DX, Qu Y, Chen Q, Zhu SN. Epidural labor analgesia is associated with a decreased risk of postpartum depression: a prospective cohort study. Anesth Analg. 2014; 119: 383-392.
11. Sebela A, Hanka J, Mohr P. Etiology, risk factors, and methods of postpartum depression prevention. Ceska Gynekol. 2018; 83: 468- 473.
12. Suhitharan T, Pham TP, Chen H, Assam PN, Sultana R, Reena Han NL, et al. Investigating analgesic and psychological factors associated with risk of postpartum depression development: a case-control study. Neuropsychiatr Dis Treat. 2016; 12: 1333-1339.
13. Lim G, Farrell LM, Facco FL, Gold MS, Wasan AD. Labor Analgesia as a Predictor for Reduced Postpartum Depression Scores: A Retrospective Observational Study. Anesth Analg. 2018; 126:1598- 1605.
14. Dunstan DA, Scott N. Clarification of the cut-off score for Zung’s self- rating depression scale. BMC Psychiatry. 2019; 19: 177.
15. Catala P, Suso-Ribera C, Carmona J, Marin Morales D, Penacoba C. Does pain after delivery unequivocally lead to postpartum depression? The moderating role of religious coping. J Reprod Infant Psychol. 2021; 1-11.
16. Lim G. Perinatal depression. Curr Opin Anaesthesiol. 2021; 34: 233- 237.
17. Lee DT, Yip SK, Chiu HF, Leung TY, Chan KP, Chau IO, et al. Detecting postnatal depression in Chinese women. Validation of the Chinese version of the Edinburgh Postnatal Depression Scale. Br J Psychiatry. 1998; 172: 433-437.
18. Kroska EB, Stowe ZN. Postpartum Depression: Identification and Treatment in the Clinic Setting. Obstet Gynecol Clin North Am. 2020; 47: 409-419.
19. Moraes GP, Lorenzo L, Pontes GA, Montenegro MC, Cantilino A. Screening and diagnosing postpartum depression: when and how? Trends Psychiatry Psychother. 2017; 39: 54-61.
20. Wicinski M, Malinowski B, Puk O, Socha M, SLupski M. Methyldopa as an inductor of postpartum depression and maternal blues: A review. Biomed Pharmacother. 2020; 127: 110196.
21. Payne JL, Maguire J. Pathophysiological mechanisms implicated in postpartum depression. Front Neuroendocrinol. 2019; 52: 165-180.