Risk and protective factors for postpartum depression among Polish women – a prospective study

Abstract

This prospective study conducted at a single center in 2022 aims to identify risk and protective factors for postpartum depression (PPD) in Polish women and to assess the impact of pregnancy, delivery, the postpartum period, and psychosocial factors on PPD. After delivery and 4 weeks later, 311 women filled out two questionnaires of our design related to risk factors for PPD. Immune Power Personality Questionnaire, Walsh Family Resilience Questionnaire, and Edinburg Postnatal Depression Scale were also applied. The predictors of PPD identified at two time points included: use of antidepressants, previous depressive episodes, family history of depression, risk of preterm delivery, anxiety about child’s health, and breastfeeding and sleep problems. Risk factors for PPD found only after delivery were: suicidal ideation before pregnancy, stressful life events, premature rupture of the membranes, and cesarean section. Inhalation analgesia during labor reduced the PPD frequency. At 4 weeks’ postpartum, regular physical activity was also predictive of PPD, while breastfeeding, financial satisfaction, and sufficient sleep duration were protective factors. PPD after delivery was negatively correlated with capacity to confide, hardiness, assertiveness, self-complexity, and communication. PPD at 4 weeks postpartum decreased belief systems, organization patterns, and communication. Two proposed self-designed questionnaires can be useful for effectively screening PPD in the Polish population.

Keywords:

• Edinburgh postnatal depression scale
• Polish women
• postnatal depression
• screening for postpartum depression
• self-completion questionnaires

Introduction

Postpartum depression (PPD) is a serious mood disorder due to postpartum-related factors, including biological changes in hormone levels [1,2]. PPD characteristically occurs during the initial 4 weeks or could last 12 months upon childbirth [3]. The symptoms include sleep disorders, loss of appetite, anxiety about the child, persistent sadness and crying, hopelessness and helplessness, difficulty concentrating, lack of interest in daily activities and hobbies, and thoughts of death and suicide [4]. The disease negatively affects the mother’s life and all family members, especially the newborn child, via changes in maternal self-esteem, mother–child interactions and parenting bonding, sensitivity, and behaviors [5,6]. As in the first year of their life, children are particularly vulnerable to the effects of PPD because of rapid brain development and maturation of key physiological systems. the risk of health problems and physiological, psychological, emotional, and psychomotor delays during infancy and early childhood is considerable [6]. Surprisingly, despite the seriousness of PPD, only about 30% of affected women are identified, and of those, 16% receive treatment [7].

Identifying the risk and protective factors for PPD is essential for early interventions to prevent potentially devastating long-term consequences. Many biological, obstetric, clinical, psychological, social, newborn care and lifestyle-related factors can play a role in developing PPD [4,8]. The most common identified risk factors are a personal or family history of psychiatric disorders (including prenatal depression), premenstrual syndrome, pregnancy and delivery-related complications, concomitant chronic diseases (gestational diabetes, anemia), neuroticism, high childcare and life stress, violent experiences, lower socioeconomic status, lack of social support, partner dissatisfaction, current or past substance abuse, unplanned pregnancy, and sleep disturbances [3,4,8–10]. In contrast, skin-to-skin care, breastfeeding, health consciousness, healthy dietary patterns (e.g. seafood and fish consumption), and supplementation of vitamins (especially vitamin D), calcium, and zinc were reported as protective factors [11,12].

Although in many European countries, the prevalence of PPD during the first year after delivery is estimated to be between 10 and 16% [13], in Poland, it is slightly higher (16–18%) [13,14]. Following the example of other countries with a long tradition of mental health monitoring [15], in 2019, Poland implemented a new standard of perinatal care, obligating a three-stage screening for PPD based on the Regulation of the Minister of Health of 16 August 2018, on the standard of organizational perinatal care [16]. Previously, the Patient Health Questionnaire-2 (PHQ-2) was used as a screening tool, and the Patient Health Questionnaire-9 (PHQ-9) was used as an extended test in Poland [16]. However, currently, screening with the Edinburgh Postpartum Depression Scale (EPDS) is recommended for pregnant women up to 1 year after giving birth, in addition to other preventive strategies: educating women, training medical staff, and carrying out specialist consultations [17].

The aim of this study was to identify risk and protective factors for PPD among Polish women to help prevent and early detect this mood disorder. Moreover, the impact of pregnancy, delivery, the postpartum period, and psychosocial factors such as personality traits and family support on PPD was analyzed.

Methods

Study design and participants

In this prospective study, 311 women who gave birth in the Specialist Hospital in Wejherowo in Poland between July and September 2022 were involved. The inclusion criteria were: at least 18 years of age and routine hospitalization after delivery (24–36 h after vaginal delivery and 36–48 h after a cesarean section). The exclusion criteria were as follows: preterm labor before the end of the 32nd week of pregnancy, neurological disease, severe illness of the child requiring special prenatal care, and death of a newborn child. All participants gave informed written consent prior to their inclusion in the study. The study was approved by Bioethics Commission at the District. Medical Chamber in Gdansk (KB − 39/22).

Rating instruments

The participants filled out two questionnaires designed by us: the Early Postnatal Questionnaire (EPQ) and the Late Postnatal Questionnaire (LPQ), and three standardized questionnaires, Immune Power Personality Questionnaire (IPPQ), Walsh Family Resilience Questionnaire – Polish Adaptation (WFRQ-PL), and Edinburg Postnatal Depression Scale (EPDS), used as per their purpose. Not all surveys were fully completed because the women skipped the questions if a given procedure or treatment did not apply to them. The questionnaires were anonymous, i.e. the participant provided her personal and contact details only if she wanted. In result, 112 out of 311 women who completed EPQ provided contact data, which made it possible to ask them 4 weeks later to complete LPQ.

EPQ included 60 questions about demographic data, the course of pregnancy and delivery, and the newborn’s condition after birth. Women completed it after giving birth, during routine hospitalization. LPQ included 12 questions about the care of the newborn, family support, and the mother’s health. It was completed 4 weeks after giving birth, during the postpartum home visit by a midwife.

IPPQ is a psychometric tool that shows the relationship of personality with various aspects of physical health. It contains 49 items (42 items measuring immune power personality traits and 7 items from the control scale measuring social approval), assessed on a 4-point scale (from “definitely agree” to “definitely disagree”) [18]. It was completed after delivery.

WFRQ is used to rate how the family is coping with crises and ongoing challenges. It consists of three main scales: belief systems (13 items), organizational processes (9 items), and communication processes (10 items). The responses were evaluated on a 5-point scale (from “rarely/never” to “almost always”). The version of WFRQ adapted to the Polish language and culture was applied (WFRQ-PL) [19]. It was completed after delivery.

EPDS is the most common self-report tool for depression screening among pregnant and postpartum women. It assesses emotional experiences over the past seven days using 10 items with a 4-point response scale (with a minimum of 0 and a maximum of 30 points). Two cutoff points are usually used: 10–11 points (slightly increased severity of PPD symptoms) and 12 or more points (increased severity of PPD symptoms) [20,21]. We applied the EPDS with a cutoff score set at 10 to identify early PPD symptoms after delivery and at 4 weeks postpartum for screening purposes (10 was included in having PPD). The EPDS had a good level of internal consistency as determined by Cronbach’s alpha of 0.69. The Fleiss’ kappa coefficient was −0.30.

Statistical analysis

All statistical analyses were performed using StatSoft Inc. (2014) STATISTICA (Data Analysis Software System), version 12.0. Quantitative variables were characterized by arithmetic mean, standard deviation (SD), and minimum and maximum values (range). Qualitative variables were presented as the number of observations and percentage.

The Shapiro–Wilk W test was used to check whether the data were normally distributed. The Levene (Brown–Forsythe) test verified the equality of variances. The statistically significant differences between the means in two unrelated groups were determined with the Student’s t-test (or the Welch’s t-test where the homogeneity of variance assumption was not met) or the Mann–Whitney U test (when data failed to meet the requirements of t-test or when the variables were ordinal). The significance of differences between more than two groups was checked by the F-test (ANOVA) or the Kruskal–Wallis test. Post hoc tests (Tukey’s or Dunn’s tests) were performed for statistically significant results. The Student’s t-test or the Wilcoxon signed-rank test was used to compare two dependent variables. The significance of differences between more than two dependent variables was checked by repeated measures analysis of variance or Friedman’s test. The Chi-Square test of independence was used for categorical variables.

Both univariate and multivariable logistic regression were applied to identify independent predictors for postpartum depression. Correlation analysis was performed, and the Pearson and/or Spearman correlation coefficients were estimated to establish the direction and strength of a relationship between variables. In all calculations, the significance level was set to p = 0.05.

Results

Basic characteristics of the sample

The data analyses were conducted for 311 women in the postpartum period. The sociodemographic variables of the sample and the basic characteristics of newborns are shown in Table 1. Briefly, the age of women ranged between 18 and 45 (average age 29.4 ± 5.1). The largest group of respondents were women who gave birth at the age of 26–30 (35.4%), followed by those aged 31–35 (29.2%), 18–25 (23.9%), and over 35 (11.5%). Most participants completed tertiary (37.5%) and upper secondary (40.1%) education. Almost all women were married (74.5%) or in a partnership (23.5%). They had an average of 2.3 pregnancies and 2.0 labors. The average week of delivery was 39.2 ± 1.9. The majority of newborns (96.6%) were in good condition, as measured by the APGAR scale. Over 60.0% of women slept 6–7 h a day, while 34.2% of the respondents slept for 5 h or less daily.

Table 1. Basic characteristics of the sample.

Variable	Total study group (n = 311)
	Mean (SD) range, or n (%)
Age, years (n = 305)	29.4 (5.1) 18.0–45.0
Body height, cm (n = 266)	166.8 (6.2) 152.0–190.0
Body weight, kg (n = 243)	80.5 (14.0) 46.0–120.0
BMI, kg/m^2 (n = 242)	28.9 (4.7) 18.0–42.0
Education (n = 307)
Primary	8 (2.6%)
Lower secondary	17 (5.5%)
Upper secondary (technical)	44 (14.3%)
Upper secondary (general)	123 (40.1%)
Tertiary	115 (37.5%)
Marital status (n = 306)
Single	4 (1.3%)
In a partnership	72 (23.5%)
Married	228 (74.5%)
Divorced	2 (0.7%)
Pregnancies (n = 305)	2.3 (1.3) 1.0–10.0
Labors (n = 299)	2.0 (1.1) 1.0–9.0
Week of delivery (n = 291)	39.2 (1.9) 26.0–42.0
Newborn’s sex (n = 304)
Female	138 (45.4%)
Male	166 (54.6%)
APGAR score in newborn at 1 min after birth (n = 229)
0–3 (Low)	1 (0.4%)
4–7 (Moderate)	6 (2.6%)
8–10 (Good)	222 (96.9%)
Maternal sleep duration postpartum, hours (n = 111)
≤5	38 (34.2%)
6–7	67 (60.4%)
8–9	6 (5.4%)
≥10	0 (0.0%)

BMI: body mass index; SD: standard deviation.

Characteristics of the sample – EPQ response rates

According to the answers given by 311 women in EPQ, almost half of the women undertook regular physical activity before pregnancy (49.8%, n = 155). During pregnancy, 20.1% (n = 62) of women continued regular exercise, and 8.8% (n = 27) of them started new physical activity. The largest number of women admitted that they had been ever diagnosed with Hashimoto’s disease (16.3%, n = 49). Fewer respondents indicated insulin resistance (5.6%), polycystic ovary syndrome (5.5%), irritable bowel syndrome (5.3%), bronchial asthma (5.2%), and other diseases (premenstrual syndrome, type 1 and 2 diabetes, pre-pregnancy hypertension – about 2.0%; celiac disease and not listed autoimmune diseases ≤1%). Before pregnancy, depressive episodes occurred in 13.0% (n = 39) of women, while postpartum depression in 4.3% (n = 13) and suicidal thoughts in 4.0% (n = 12) of the respondents. Antidepressants were used before and during the current pregnancy by 4.6% (n = 14) and 2.0% (n = 6) of respondents, respectively. The family members of 15.5% (n = 47) of women had depression.

During the current pregnancy, 8.6% (n = 26) of women suffered from gestational diabetes and 1.3% (n = 4) from pre-eclampsia. Hypertension was diagnosed in 2.0% (n = 6) of women before the 20^th week of pregnancy and 6.3% (n = 19) of women after this period. Moreover, 7.6% (n = 23) of participants took alpha-methyldopa (Dopegyt) for hypertension. Of the surveyed women, 21.1% (n = 64) experienced a stressful life events unrelated to pregnancy. Besides, 36.2% (n = 110) of the respondents were hospitalized in the Department of Pregnancy Pathology, 16.7% (n = 51) had vaginal bleeding, 9.2% (n = 28) had premature rupture of membranes, and 12.6% (n = 38) were at risk of preterm birth. Steroids for preventing neonatal respiratory distress syndrome were administered in 8.9% (n = 27) of women. Nearly one-third of the respondents (32.9%, n = 100) took progesterone or its derivatives to prevent miscarriage (vaginal lutein in 63.0% of cases, sublingual lutein in 24.0%, Duphaston in 45.0%, other drugs in 5.0%).

The rate of deliveries by cesarean section was 26.5% (n = 81), and the rate of vaginal deliveries was 73.5% (n = 230). Detailed characteristics of the factors related to the labor process are shown in Table 2. In the study group, 8.1% (n = 25) of women were concerned about the child’s health after delivery. Every ninth child required a stay in a neonatal unit (8.6%, n = 26). Almost all respondents stated that the help of midwives in caring for the child was adequate (96.7%, n = 295). Overall, 93.8% (n = 285) of women intended to breastfeed, and 82.6% (n = 251) of them considered their breastfeeding knowledge sufficient. Slightly more than 90% of the participants indicated that the breastfeeding support from midwives in a maternity ward was satisfactory (91.4%, n = 267).

Table 2. Characteristics of the sample in terms of childbirth based on EPQ.

Variable	Total study group (n = 311)
	n/Total number of answers (%)
Cesarean section	81/306 (26.5%)
Planned	39/77 (50.7%)
In an emergency	38/77 (49.3%)
Induction of labor:
Foley catheter	47/222 (21.2%)
Prostaglandins	14/214 (6.5%)
Oxytocin drip infusion	65/223 (29.1%)
Anesthesia during labor	120/229 (52.4%)
Effective anesthesia	111/140 (79.3%)
Gas and air (Entonox)	55/138 (39.9%)
Intravenous anesthesia (Ultiva)	81/140 (57.9%)
Epidural anesthesia	7/129 (5.4%)
Episiotomy	90/234 (38.5%)
Perineal lacerations	67/235 (28.5%)
Vacuum-assisted delivery	5/222 (2.3%)
Sufficient support from the partner during hospitalization	205/226 (90.7%)
Support from the birth partner	173/245 (70.6%)
Willingness to be supported by the birth partner during the next pregnancy	200/251 (79.7%)
Birth plan	68/305 (22.3%)
Education in childbirth school	89/307 (29.0%)
Opinion that education in childbirth school reduces stress during labor	89/223 (39.9%)
Skin-to-skin contact after birth	279/301 (92.7%)

EPQ: Early Postnatal Questionnaire.

Characteristics of the sample – LPQ response rates

LPQ was completed by 112 women 4 weeks after giving birth. More than half of the respondents undertook regular physical activity (53.6%, n = 60). Every fifth woman raised concerns about the child’s condition (20.0%, n = 22), and in 19.1% (n = 21) of cases, the child required a visit to the doctor due to health problems. Although 80.4% (n = 90) of women breastfed, 35.7% (n = 40) of them had difficulties with lactation. Only 5.4% (n = 6) of women smoked cigarettes. Almost all women believed that the partner’s help in caring for the child was sufficient (93.7%, n = 104) and that they could count on the help of the family (91.9%, n = 102). A tiny percentage of women (3.6%, n = 4) took antidepressants. Less than 40.0% (n = 44) of women stated that they slept enough hours a day, while 20.5% (n = 23) of respondents had trouble sleeping. Nearly 80.0% (n = 89) of women were satisfied with their financial situation.

Characteristics of the sample – IPPQ, WFRQ-PL, and EPDS score

Characteristics of the sample in terms of the results of IPPQ, WFRQ-PL, and EPDS were presented in Table 3. The mean value of postpartum depression measured with EPDS was 6.0 ± 4.0 (range 0.0–21.0) after delivery and 8.8 ± 5.9 (range 0.0–21.0) at 4 weeks postpartum.

Table 3. Characteristics of the sample in terms of the results of IPPQ, WFRQ-PL, and EPDS.

Questionnaire items	Total study group (n = 311)
	Mean (SD) range
IPPQ
Attend, connect, and express (ACE) (n = 308)	15.1 (5.8) 0.0–24.0
Capacity to confide (n = 309)	14.5 (6.1) 0.0–24.0
Hardiness (n = 310)	16.7 (6.3) 0.0–24.0
Assertiveness (n = 309)	16.2 (6.6) 0.0–24.0
Affiliative trust (n = 310)	18.5 (6.8) 0.0–24.0
Healthy helping (n = 309)	13.5 (5.7) 0.0–24.0
Self-complexity (n = 307)	14.1 (5.9) 0.0–25.0
Social approval (n = 311)	18.6 (7.2) 0.0–28.0
Global score (n = 310)	107.8 (40.7) 0.0–161.0
WFRQ-PL
Belief systems (n = 311)	48.8 (10.0) 28.0–65.0
Organization patterns (n = 311)	30.5 (6.6) 18.0–40.0
Communication/problem-solving (n = 311)	39.5 (8.3) 20.0–50.0
Global score (n = 311)	42.4 (58.8) 0.0–155.0
EPDS
After delivery (n = 282)	6.0 (4.0) 0.0–21.0
At 4 weeks postpartum (n = 112)	8.8 (5.9) 0.0–21.0

EPDS: Edinburg Postnatal Depression Scale; IPPQ: Immune Power Personality Questionnaire; SD: standard deviation; WFRQ-PL: Walsh Family Resilience Questionnaire – Polish Adaptation.

Regression analysis for risk and protective factors of PPD based on EPQ and LPQ

The impact of the statistically significant factors from EPQ and LPQ on PPD measured with EPDS (after delivery and at 4 weeks postpartum) was presented in Table 4.

Table 4. The effect of selected parameters from EPQ and LPQ on postpartum depression measured with EPDS after delivery and at 4 weeks postpartum (univariate regression analysis).

Parameters	Postpartum depression
	After delivery (n = 311)		At 4 weeks postpartum (n = 112)
	β (95% CI)	p-Value	β (95% CI)	p-Value
EPQ
Depressive episodes before pregnancy	0.30	<0.0001	0.29	0.0024
	(0.18; 0.41)		(0.11; 0.48)
Suicidal ideation before pregnancy	0.28	<0.0001	NS	NS
	(0.16; 0.39)
Antidepressants used before pregnancy	0.15	0.0153	0.22	0.0196
	(0.03; 0.26)		(0.04; 0.41)
Family history of depression	0.14	0.0165	0.26	0.0054
	(0.03; 0.26)		(0.08; 0.45)
Stressful life event not related to pregnancy	0.15	0.0126	NS	NS
	(0.03; 0.27)
Premature rupture of the membranes	0.14	0.0244	NS	NS
	(0.02; 0.25)
Risk of preterm delivery	0.17	0.0055	0.21	0.0274
	(0.05; 0.28)		(0.02; 0.40)
Cesarean delivery	0.14	0.0198	NS	NS
	(0.02; 0.26)
Inhalation analgesia (Entonox)	−0.19	0.0311	NS	NS
	(−0.36; −0.02)
Anxiety about newborn’s health	0.15	0.0097	0.20	0.0314
	(0.04; 0.27)		(0.02; 0.39)
LPQ
`Regular physical activity	NS	NS	0.25	0.0069
			(0.07; 0.44)
Anxiety about child’s health	NS	NS	0.40	<0.0001
			(0.23; 0.58)
Breastfeeding	NS	NS	−0.2	0.0143
			(-0.41; −0.05)
Breastfeeding problems	0.20	0.0373	0.30	0.0011
	(0.01; 0.39)		(0.12; 0.48)
Antidepressants use	0.19	0.0459	0.21	0.0258
	(0.01; 0.38)		(0.03; 0.40)
Adequate hours of sleep per day	NS	NS	−0.29	0.0022
			(−0.47; −0.11)
Sleep problems	0.19	0.0454	0.38	<0.0001
	(0.01; 0.38)		(0.21; 0.56)
Satisfaction with financial situation	NS	NS	−0.25	0.0087
			(−0.43; −0.06)
Average hours of sleep per day
≤5	0.20	0.0387	0.46	<0.0001
	(0.01; 0.39)		(0.29; 0.63)
6–7	NS	NS	−0.38	<0.0001
			(−0.55; −0.20)

Only statistically significant factors were included in the table. β: regression coefficient; CI: confidence interval; EPDS: Edinburg Postnatal Depression Scale; EPQ: Early Postnatal Questionnaire; LPQ: Late Postnatal Questionnaire; NS: not significant (p > 0.05).

Univariate regression analysis showed that the risk of PPD after delivery was associated with the use of antidepressants and the occurrence of depressive episodes and suicidal ideation before pregnancy, as well as a family history of depression (Table 4). In addition, PPD depended on the experience of a stressful life situation not related to the current pregnancy, premature rupture of the membranes, risk of preterm delivery, cesarean section, and anxiety about the newborn’s health. On the other hand, inhalation analgesia during labor reduced the PPD frequency. After delivery, breastfeeding problems, using antidepressants, trouble sleeping, and sleeping 5 h or less per day increased the risk of PPD.

At 4 weeks postpartum, the risk factors for PPD included: depressive episodes and the use of antidepressants before pregnancy, family history of depression, risk of preterm delivery, and feeling anxious about the newborn’s health (Table 4). Moreover, a mother’s risk of developing PPD was associated with undertaking regular physical activity, concerns about the child’s health, breastfeeding problems, using antidepressants, sleep problems, and sleeping 5 h or less per day. On the other hand, the protective factors for PPD included: breastfeeding, satisfaction with the financial situation, adequate hours of sleep per day, and sleeping 6–7 h per day.

Multivariate regression analysis showed that only suicidal ideation before pregnancy was statistically significantly associated with increased PPD measured by EPDS after delivery (p = 0.0013) (Table 5). Undertaking regular physical activity (p = 0.0024), anxiety about the child’s health (p = 0.0170), and sleep problems (p = 0.0045) were risk factors for PPD measured by EPDS at 4 weeks postpartum (Table 5).

Table 5. The effect of selected parameters from EPQ and LPQ on postpartum depression measured with EPDS after delivery and at 4 weeks postpartum (multivariate regression analysis*).

Parameters	Postpartum depression
	After delivery (n = 311)		At 4 weeks postpartum (n = 112)
	β (95% CI)	p-Value	β (95% CI)	p-Value
EPQ
Suicidal ideation before pregnancy	−0.33	0.0013	NS	NS
	(−0.52; −0.13)
LPQ
Regular physical activity	NS	NS	−0.23	0.0024
			(−0.38; −0.09)
Anxiety about child’s health	NS	NS	−0.21	0.0170
			(−0.37; −0.04)
Sleep problems	NS	NS	−0.24	0.0045
			(−0.40; −0.08)

*Multivariate regression analysis included only statistically significant parameters from univariate analysis (Table 4).

Only statistically significant factors were included in the table. β: regression coefficient; CI: confidence interval; EPDS: Edinburg Postnatal Depression Scale; EPQ: Early Postnatal Questionnaire; LPQ: Late Postnatal Questionnaire; NS: not significant (p > 0.05).

Correlation analysis between the IPPQ and WFRQ-PL subscales and PPD

Correlation analysis between the IPPQ and WFRQ-PL subscales and the selected sociodemographic parameters (age, body height, body weight, BMI, education, pregnancies, labors, week of delivery, APGAR score in a newborn) showed that an increase in the education level promoted the IPPQ values of hardiness (r = 0.14, p = 0.0119), self-complexity (r = 0.20, p = 0.0004) and social approval (r = 0.13, p = 0.0283) as well as the WFRQ-PL values of communication processes (r = 0.21, p = 0.0272) and global score (r = 0.13, p = 0.0255). The communication also correlated with the APGAR score (r = 0.25, p = 0.0197). The remaining correlations were not statistically significant.

Correlation analysis between the subscales of IPPQ and PPD measured with EPDS after delivery revealed that the PPD was negatively associated with the value of capacity to confide (r = −0.23, p = 0.0001), hardiness (r = −0.15, p = 0.0144), assertiveness (r= −0.21, p = 0.0005), self-complexity (r = −0.16, p = 0.0090), and global score (r = −0.17, p = 0.0047) (Table 6). Correlations at 4 weeks postpartum were not statistically significant.

Table 6. Correlation between the subscales of IPPQ and WFRQ-PL and postpartum depression measured with EPDS after delivery and at 4 weeks postpartum (correlation analysis).

Subscales	Postpartum depression
	After delivery (n = 311)		At 4 weeks postpartum (n = 112)
	r	p-Value	r	p-Value
IPPQ
Capacity to confide	−0.23	0.0001	NS	NS
Hardiness	−0.15	0.0144	NS	NS
Assertiveness	−0.21	0.0005	NS	NS
Self-complexity	−0.16	0.0090	NS	NS
Global score	−0.17	0.0047	NS	NS
WFRQ-PL
Belief systems	NS	NS	−0.59	<0.0001
Organization patterns	NS	NS	−0.58	<0.0001
Communication/problem-solving	−0.23	0.0168	−0.59	<0.0001
Global score	−0.20	0.0398	−0.62	<0.0001

Only statistically significant factors were included in the table. EPDS: Edinburg Postnatal Depression Scale; IPPQ: Immune Power Personality Questionnaire; r: correlation coefficient; NS: not significant (p > 0.05); WFRQ-PL: Walsh Family Resilience Questionnaire – Polish Adaptation.

The increase in PPD measured with EPDS after delivery was negatively correlated with communication (r = −0.23, p = 0.0168) and WFRQ-PL global score (r = −0.20, p = 0.0398) (Table 6). PPD at 4 weeks postpartum decreased the value of belief system (r = −0.59, p < 0.0001), organization patterns (r = −0.58, p < 0.0001), communication (r = −0.59, p < 0.0001) and WFRQ-PL global score (r = −0.62, p < 0.0001).

Discussion

In Poland, since 2019, an obligation for screening for PPD was introduced within a new standard of perinatal care [16]. Although medical staff can use any questionnaires that comply with current medical knowledge, EPDS is the recommended risk assessment tool [17]. However, the appropriate time to administer the EPDS is still under question [22,23]. According to Lee et al. [23], its psychometric properties were unsatisfactory when EPDS was administered immediately after delivery. Only the depression rating scales applied in the second and third postpartum months were shown to be valid, reliable, and useful in detecting PPD [23]. Even though more than one-third of women reached 12 points in the first week after delivery [24], it should be expected that EPDS scores significantly decrease within one month after delivery [22].

Moreover, the discrepancy in the EPDS results in face-to-face contact and on the online platform was observed. Ten times higher average scores were obtained in online self-screening than in the questionnaires filled in the presence of a midwife [15]. The limitations of EPDS in distinguishing PPD from other mental health problems should also be emphasized [25]. In the face of EPDS limitation, two questionnaires of our design, intended to be completed by women at the beginning of the postpartum period and 4 weeks later, may improve the certainty of a PPD diagnosis, thereby supporting effective screening in the Polish population through proper assessment of risk factors.

Although several studies have identified prognostic variables for PPD in the Polish population [24,26–30], no extensive joint analysis of the different types of risk factors influencing the development of PPD has been carried out so far. The results of our study, examining various obstetric, clinical, psychological, and social risk and protection factors for PPD, are generally consistent with other research findings when it comes to the significant impact of previous depressive episodes, family history of depression, stressful life events, anxiety about child’s health, and breastfeeding problems on PPD [1,31]. Prior depression and other psychiatric disorders are well-established prognostic factors for PPD [32,33]. It was found that the risk of PPD for women with a depression history was over 20 times higher than for women without [1]. Nevertheless, the results of the multivariate regression analysis showed that only suicidal ideation before pregnancy and anxiety about the child’s health were associated with PPD among all psychological factors included in our study. However, it is worth mentioning that suicidal ideation, anxiety, or stress could potentially be confounders, symptoms, or third variables rather than independent predictors of PPD.

Surprisingly, in contrast to other research [34], regular physical activity was prognostic for PPD at 4 weeks postpartum in the multivariate regression analysis. One possible explanation could be that the women in the postpartum period tried to take up physical activity beyond their strength at the pre-pregnancy level, which was impossible to achieve and resulted in a depressed mood.

The results of Huang et al. indicated that depressed mothers had poorer sleep quality than non-depressed mothers during the early postpartum period, which leads to more daytime dysfunctions [35]. However, the driving force of the relationship between sleep disturbance and PPD symptoms has not been clarified. It is uncertain whether sleep deprivation contributes to PPD or depression causes trouble sleeping [36], similarly as the relationship between breastfeeding and PPD may be bidirectional: not engaging in breastfeeding may increase the risk of PPD, while depression may reduce rates of breastfeeding [37]. In our study, sleep problems were risk factor for PPD at 4 weeks postpartum, according to the multivariate regression analysis. Interestingly, sufficient sleep duration (6–7 h per day) was a protective factor for PPD, similar to breastfeeding.

As in our study, several authors reported that PPD occurred more frequently in women who had undergone cesarean section, especially in an emergency [30,33]. Most studies also supported the association between preterm birth and PPD [38]. However, cesarean section as a risk factor for PPD is still discussed as not all studies have found a relationship between delivery methods and PPD [39]. The effect of cesarean section on the risk of PPD may be modified by other factors, e.g. cultural norms regarding motherhood and child care. In Poland, the percentage of cesarean sections is one of the highest in Europe (over 40%) [39]. Simultaneously, social expectations for mothers are demanding, which may lead to exhaustion and guilt in women after a cesarean section associated with physical discomfort and difficulty in performing functional activities. A higher level of pain experienced after cesarean delivery compared to vaginal delivery may explain the correlation of PPD with cesarean section and its severity [39]. Moreover, fear of childbirth, followed by concern for fetal health and fear of pelvic floor damage may affect the woman’s preference for cesarean delivery on maternal request, and later translate into mood disorders [40].

Our data also showed that inhalation analgesia during labor decreased the PPD frequency after delivery. Although there is evidence to support a reduction by labor epidural analgesia of risk for PPD, nitrous oxide use has not been associated with PPD upon discharge so far [41,42].

The results of the present study did not confirm the significant effect of partner relationships on PPD [43]. However, in our sample, over 90% of respondents declared satisfaction with the partner’s help during hospitalization and in caring for the child.

Our study analyzed the impact of immune power personality traits distinguished in 1996 by Dreher [18] on PPD. As our study showed, PPD after delivery was negatively correlated with the capacity to confide, hardiness, assertiveness, and self-complexity. These traits can be regarded as effective coping strategies that allow one to deal with emotions and new social situations related to childbirth [18]. Among other personality traits, neuroticism was most widely studied concerning PPD, and its association with high levels of PPD is hardly in doubt [44,45]. Furthermore, perfectionism and self-criticism predicted depressive symptoms in the postpartum period [44]. On the other hand, extraversion and consciousness were negatively correlated with PPD 2 weeks after delivery [45]. It was found that personality traits did not have a direct but a mediated impact on postnatal depression [45]. The capacity to confide; hardiness, assertiveness, and self-complexity may also reflect symptoms of PPD rather than risk or protective factors.

Lack of postnatal family support is an important risk factor for PPD [1]. Our study confirmed the impact of family support on PPD, according to WFRQ-PL [19,46]. PPD after delivery and at 4 weeks postpartum was negatively correlated with communication processes. It refers to families’ abilities to approach adversity with clarity, support and express appropriate emotional responses to adversity, and engage in collaborative problem-solving [46]. A high level of PPD at 4 weeks postpartum was associated with low levels of all WFRQ-PL subscales: besides communication, belief system and organization patterns were also decreased. Belief systems refer to families’ abilities to make meaning of adversity, maintain positive outlooks, and draw strength from spirituality and transcendence, while organizational patterns refer to families’ abilities to maintain flexibility, maintain connectedness, and draw from social and economic resources [46]. However, the relationship between family resilience and PPD may be bidirectional, similar to communication problems: lack of family support may increase the level of PPD, and PPD may influence the families’ abilities to act as a functional system that can engage in coping and adaptational processes. In our study, communication processes were positively correlated with education level. As was shown in other studies, a lower education level was an independent risk factor for postpartum depression [47].

Limitations

The study was conducted at a single center in Poland, which limits the generalization of the results to other populations, especially because of the specific socio-economic and cultural background. Assessment of the incidence of PPD was performed using screening questionnaires, which may be a source of bias. Reaching a larger number of participants was impossible due to anonymity of the questionnaires. The prevalence of PPD measured with EPDS depends on the cutoff value of the study. The study did not include a pre-delivery evaluation of depression status.

Conclusions

There has been increasing focus on the importance of early and accurate detection and treatment of PPD because of the serious consequences of this mental disorder for the mother and the child. The results of our study demonstrate that PPD requires a multifactorial approach. Particular attention should be paid to screening women postpartum as part of preventive health care programs to identify the risk factors for PPD. It will allow for further assessment of the severity of depressive symptoms and implementation of appropriate treatment.

Author contributions

SK and MB conceived and designed the study. SK collected the data. DŚ performed statistical analysis.

Ethical approval

The study was approved by Bioethics Commission at the District. Medical Chamber in Gdansk (KB − 39/22). All participants gave informed written consent prior to their inclusion in the study and were informed about the publication of study results.

Acknowledgments

The authors are grateful to Anna Jesionek, PhD (Proper Medical Writing sp. z o.o.) for medical writing support and Dorota Szymańska (Proper Medical Writing sp. z o.o.) for editorial support. This research received no funding.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

The data analyzed during the current study are available from the corresponding author upon reasonable request.

Additional information

Funding

The author(s) reported there is no funding associated with the work featured in this article.