Childbirth experience, risk of PTSD and obstetric and neonatal outcomes according to antenatal classes attendance

Antenatal classes have evolved considerably and include now a discussion of the parents' birth plan. Respecting this plan normally results in a better childbirth experience, an important protective factor of post-traumatic stress disorder following childbirth (PTSD-FC). Antenatal class attendance may thus be associated with lower PTSD-FC rates. This cross-sectional study took place at a Swiss university hospital. All primiparous women who gave birth to singletons from 2018 to 2020 were invited to answer self-reported questionnaires. Data for childbirth experience, symptoms of PTSD-FC, neonatal, and obstetrical outcomes were compared between women who attended (AC) or not (NAC) antenatal classes. A total of 794/2876 (27.6%) women completed the online questionnaire. Antenatal class attendance was associated with a poorer childbirth experience (p = 0.03). When taking into account other significant predictors of childbirth experience, only induction of labor, use of forceps, emergency caesarean, and civil status remained in the final model of regression. Intrusion symptoms were more frequent in NAC group (M = 1.63 versus M = 1.11, p = 0.02). Antenatal class attendance, forceps, emergency caesarean, and hospitalisation in NICU remained significant predictors of intrusions for PTSD-FC. Use of epidural, obstetrical, and neonatal outcomes were similar for AC and NAC.


Scientific Reports
| (2022) 12:10717 | https://doi.org/10.1038/s41598-022-14508-z www.nature.com/scientificreports/ (5 items), Avoidance (2 items), Negative alterations in cognition and mood (7 items) and Alterations in arousal or reactivity (6 items), each item ranging from 0 =Not at all to 4 =Extremely. In this study, the Cronbach alpha was calculated as 0.89. Women also completed two questions of the Major Life Events Questionnaire 32,33 about cases of violence or abuse before birth, as this is a risk factor for PTSD 18 and for negative childbirth experience 34 . The third group of outcomes were obstetric outcomes (i.e., gravidity, maternal age at birth, induction of labor, oxytocin augmentation, analgesia, mode of birth) and neonatal outcomes (i. e., Apgar score at 1, 5 and 10 min, birth weight, and neonatal intensive care unit (NICU) admission), all of which were extracted from digital medical records. Data extracted from medical records comprised a medical file number, which was linked in an Excel table to the name of the patient and her RedCap number.
Demographic information (country of origin, civil status, educational background, employment status, and Body Mass Index (BMI)) was collected via self-report questionnaires. Furthermore, this study included all the antenatal classes that women attended, regardless of their specific methods or settings (at the hospital or in private settings) and women self-reported their attendance of antenatal classes and the number of attended sessions. Data analysis. Analyses were conducted with SPSS (Statistical Package for Social Sciences, version 26.0). CEQ2, PCL-5, obstetric, and neonatal outcomes were compared between the two groups, participation in antenatal classes (AC) versus no participation in antenatal classes (NAC), using independent sample t tests, Chi2 tests or Fischer exact tests. Bi-variate correlations (One-way ANOVA) were carried out to investigate which variables of interest (including post-hoc exploratory analyses) were related to the childbirth experience. Finally, regression analyses were conducted with all variables that were positively correlated by forcing the variable 'participation in antenatal classes (yes/no)' into the regression (stepwise hierarchical regression). For the regression of the CEQ-2 score (dependant variable), the variable 'participation in antenatal classes' was entered in the first step as independent variable. In the second step, the other independent variables were entered, including history of violence or abuse in the last two years, civil status, employment status, and time since birth, induction of labor, analgesia, forceps, emergency caesarean, operative delivery (all deliveries except spontaneous vaginal birth), Apgar score at 1 min, Apgar score at 5 min, and NICU admission. For the regression of PCL-5, the same model was used, except for the time since birth, as this was not correlated with the PCL-5 total score.
Depending on the question, the rate of missing responses varied from 16% to 21.7% for the CEQ-2 and from 29 to 29.4% for the PCL-5. Missing data for PCL-5 or CEQ-2 were managed using pairwise deletion at item level. No missing data were replaced. No data were missing for demographic, obstetric or neonatal outcomes.
Comparing those who had attended antenatal classes (AC) with those who had not (NAC), those in the AC group were older, with a lower weight (p < 0.05), more likely to have completed a university education, and to exercise an intellectual and scientific profession (p < 0.01; see Table 1).
With regards to maternal age and migrant status, the study sample was representative of the population in the catchment area of the university hospital (Canton Vaud) 35,36 . The sample over-represented women who had a partner or were married (69.1% in our study versus 49% in the canton of Vaud), as well as women with a high level of education (71% in our study versus 42% in the canton of Vaud 35 . Across the whole sample, the PCL-5 total score was negatively correlated with the CEQ-2 total score (p < 0.001), indicating that a better childbirth experience was associated with a lower risk of PTSD-FC symptoms.
Childbirth experience. The mean CEQ-2 total score was 3.06 (SD = 0.62). The mean CEQ-2 total score (p < 0.05), and the mean CEQ-2 own capacity score (p < 0.05) were lower for the AC group compared to the NAC group, which means that women who attended antenatal classes reported a less positive childbirth experience than women who did not attend antenatal classes (see Table 2).
When calculating bivariate correlations between all study variables, the CEQ-2 total score and CEQ-2 subscale scores Own Capacity, Perceived Safety, and Participation were negatively correlated with: the completion time from birth, induction of labor, forceps emergency caesarean, operative delivery, and low Apgar (< 7) at 1 min. Furthermore, the CEQ-2 total score was positively correlated with civil status. In addition, "Own Capacity" was positively correlated with increasing maternal age at birth. "Own Capacity" and "Perceived Safety" were significantly correlated with type of analgesia: the lower mean score of "Perceived Safety" was associated with rachi-anaesthesia (M = 2.95; SD = 0.72), while the higher mean score of intrusion was associated with local anaesthesia, pudendal nerve block, EMONO (Nitrous Oxide/Oxygen 50%/50%) (M = 3.45; SD = 0.55). No analgesia was associated with a mean score of perceived safety of 3.29 ± 0.66, higher than the overall average score for the whole sample (3.09 ± 0.74). Finally, "Perceived Safety" was also significantly associated with hospitalisation of the newborn in the NICU (see Table 3 for details).
A post-hoc analysis of the CEQ-2 scores according to the antenatal classes attendance was done taking into account the data collection time. The mean CEQ-2 total score (p < 0.05) and the mean CEQ-2 own capacity score (p < 0.05) remained significantly lower in the AC group for a data collection time under 6 months after the birth. However, this difference disappeared for the data collection time up to 6 months after the birth, with the exception of the CEQ-2 subscale "Perceived safety", which was found to be significantly higher for the NAC group when the data collection time was between 18 to 24 months (supplementary material). www.nature.com/scientificreports/ When entering all significant correlations with childbirth experience into a stepwise hierarchical regression, induction of labor, use of forceps, emergency caesarean section, and civil status remained significant negative predictors of childbirth experience, whereas antenatal class attendance was not retained (see Table 4). www.nature.com/scientificreports/ PTSD-FC. The mean PCL-5 total score was 7.89 (SD = 0.58). Twenty (3.26%) participants had a total score ≥ 31, which represents the cut-off for a probable PTSD diagnosis. The mean Intrusion score was lower in the AC group (p < 0.05) compared to the NAC group (see Table 2). The total score and subscale scores Intrusion and Avoidance were positively correlated with an induction of labor, an emergency caesarean, and NICU admission. In addition, PCL-5 total score and subscale scores Avoidance and Cognitions were positively correlated with employment status. The PCL-5 total score and subscale scores Cognitions and Arousal were negatively www.nature.com/scientificreports/ correlated with violence or abuse in the last two years before birth. Intrusion, Avoidance, and Cognitions were positively correlated with operative delivery. Intrusion was correlated with analgesia: the higher mean score of intrusion was associated with general anaesthesia (M = 1.83;SD = 1.94), while the lower mean score of intrusion was associated with local anaesthesia, pudendal nerve block, EMONO (Nitrous Oxide/Oxygen 50%/50%) (0.55 ± 1.64). No analgesia during childbirth was associated to a mean score of intrusion (M = 1.19; SD = 2.11), lower than the mean score for the whole sample (M = 1.28; SD = 2.34); Avoidance was positively correlated with low Apgar (< 7) at 1 min, while Intrusion and Avoidance were negatively correlated with Apgar score at 5 min (see Table 3).
As the influence of time on the PCL-5 score was already known, a post-hoc analysis of the scores according to the antenatal classes' attendance was done, taking into account the data collection time. PCL-5 Intrusion and Avoidance scores were significantly lower in the AC group for a data collection time under 6 months after the birth. Six to 12 months after the birth, all the PCL-5 scores were significantly lower in the AC group. After 12 months, only the PCL-5 Avoidance score was lower in the AC group when the data collection time was from 18 to 24 months after the birth but was higher for the AC group when the data collection time was from 12 to 18 months and after 24 months after the birth (supplementary material).
When entering all significant correlations with PCL-5 into multiple linear regressions (stepwise hierarchical regression), antenatal class attendance remained a significant predictor of the PCL-5 Intrusion score, as well as the use of forceps, emergency caesarean, and NICU admission (see Table 5).
Obstetric and neonatal outcomes. No significant differences were found between both groups (AC and NAC) regarding obstetric outcomes (fertility treatment, mode of delivery induction of labor, oxytocin augmentation) or neonatal outcomes (Apgar scores and the birth weight of the baby). Less newborns with low Apgar scores (< 7) at 5 min were reported in the AC group, with a trend towards significance (p = 0.05). Regarding especially the use of analgesia, no significant difference was found between the AC and NAC groups (see Table 1).

Discussion
This cross-sectional study compared women regarding their childbirth experience, their PTSD-FC symptoms, as well as their obstetrical and neonatal outcomes according to their participation or not in antenatal classes (AC vs. NAC). Women who attended antenatal classes had a poorer childbirth experience but were less likely to develop birth-related intrusion symptoms. Obstetric and neonatal outcomes were comparable between both groups. Women who had attended antenatal classes reported a more negative childbirth experience, even though most of the factors associated with the childbirth experience (frequency of induction of labor, use of forceps, and emergency cesarean section) did not differ between those two groups. Studies so far showed inconsistent results regarding the link between antenatal class attendance and childbirth experience 34,37,38 . There may be different explanations for this. First, data collection occurred at different time points in different studies, from five months to five years after the childbirth, and comparisons between studies are therefore difficult. Little is actually known about the role that time since childbirth plays in the reporting of the childbirth experience. Using a five-point Likert scale, Maimburg and colleagues, showed that only 51% of women gave the same evaluation of their childbirth experience over time (from six weeks post-partum to five years post-partum); for 40% of them, the score decreased over time, while for 9% of participants, the childbirth experience score increased over time 39 . In our study, the data collection occurred from 45 days to two years after chilbirth. This variability regarding time since childbirth may have influenced our results, as we find a negative corelation between CEQ-2 total score and subscales and completion time since birth. The post-hoc analysis of the CEQ-2 scores according to the antenatal class attendance, taking into account the data collection time, shows the importance of the time that passes between the birth and the completion of the questionnaire, since the only significant difference in the birth experience scores was seen for women who completed the questionnaire less than 6 months after the birth. Second, differences in the content of the antenatal classes could contribute to explaining those differences in childbirth experience across the studies. For example, depending on the content of the antenatal classes, mothers' sense of control may be strengthened 34 . However, if the content of the antenatal classes is not matched with the reality of birth, mothers may develop unrealistic expectations 34 ; the non-fulfilment of these expectations may in turn negatively affect their childbirth experience 40 .
The prevalence of 3.26% of patients with PTSD-FC symptoms in our sample is in line with prevalence rates found in community samples 13,14 . Compared to women who did not attend antenatal classes, women who attended antenatal classes had less symptoms of intrusion. The post-hoc analysis shows that for women who gave birth less than 6 months before completing the survey, the intrusion and avoidance scores are significantly lower in the AC group as all PCL-5 scores for women who gave birth between 6 and 12 months before completing the survey. The PCL-5 score is the highest of the study in the NAC group for women who completed the questionnaire between 6 and 12 months after the birth (M = 10.73 (± 11.44)). One possible explanation is that the childbirth occurred during the COVID-19 period. However, only 18.3% of the births in this sub-sample took place during the semi-lockdown period (16 March 2020 to 19 June 2020) and the PCL-5 score for the antenatal Table 5. Results of multiple linear regression analyses for variables predicting PCL-5. B = unstandardized regression coefficient; β = standardized regression coefficient; 95% CI = 95% bias corrected and accelerated confidence intervals of unstandardized regression coefficient as estimated by means of bootstrapping. Bold regression coefficients are significantly different from 0 (p < .05). PCL-5 = Posttraumatic Stress Disorder Checklist for DSM 5. www.nature.com/scientificreports/ classes group is the lowest of the study (M = 7.06 ± 7.46). We therefore can only conclude that the relation between PTSD-FC symptoms and antenatal class attendance is more marked between 6 and 12 months after the birth. It is also important to note that PCL-5 scores are relatively higher the more time had passed since the birth in both groups (with the exception of the NAC group between 6 and 12 months after birth). The literature suggests that PCL-5 scores tend to decline over time 41 . The fact that our results show a different trend leads to the question of a possible selection bias.Women in the NAC group in our study reported a significantly lower educational level, a factor also known to predispose them to a higher risk of PTSD-FC 42 . In Switzerland, access to antenatal classes is not free of charge, which may have excluded women with lower financial means. Moreover, women in the AC group were older than those in the NAC group, which may have increased their risk of PTSD-FC 13 . However, we found higher PCL-5 scores (total and subscales) in the younger group (NAC) and no correlation between age and PCL-5 score. The link between birth preparation and PTSD-FC symptoms therefore appears to be very complex to measure, as many individual variables are involved. No differences were found for obstetric or neonatal outcomes between the AC and the NAC groups, except for APGAR scores at 5 min of life, which were better in the AC group. The overall rate of cesarean sections in the study sample was 21.6%. This is slightly lower than the hospital rate of 27% during the study period 43 , which comprises term and preterm, primiparous, and multiparous cesarean sections. Other studies have reported conflicting results about the associations between antenatal class attendance and the mode of delivery 44 . This implies again that the format and content of the antenatal classes is important. Yet, it seems that the most optimal format has not yet been found and scientifically validated 44 . Regarding the use of analgesia and particularly the use of an epidural, this study showed no significant differences between groups. Even if the main historical outcome of the antenatal classes was the management of pain, in this study, as well as in others, no significant associations between birth preparedness and reported pain level during labor or the use of analgesics during labor were found [45][46][47] .
One of the strengths of this study is that it did not seek to evaluate a specific birth preparation program but investigated associations between antenatal classes whatever the type of antenatal classes and childbirth experience, PTSD-FC symptoms, obstetrical, and neonatal outcomes in a routine clinical context. Another strength of our study was the use of multiple validated questionnaires in French and English in order to access a larger population than only the French-speaking population. The large sample size is higher than the a-priori sample size calculation, which reinforces the power of the analysis.
However, this study has a number of limitations. First, it is a retrospective study, and a retrospective bias to the reporting of outcomes may therefore not be excluded. Second, given the cross-sectional desing, no causal relationships could be investigated. Moreover, this design did not allow us to take into account an important variable: the emotional state of the women before the birth, including any previous traumatic experience or PTSD. Furthermore, this study included all the antenatal classes that women attended, regardless of their specific methods or settings (at the hospital or in private settings) and women self-reported their attendance in antenatal classes. Additionally, the low response rate (27.6%) is also an important limitation, although it is comparable to other questionnaire studies 20,48,49 , particularly to online surveys 50,51 . It is possible that women with traumatic childbirth experiences, particularly following emergency caesarean sections, did not participate in this study. Of note, preterm deliveries, known to increase the risk of PTSD, were excluded from this study. Finally, the fact that the questionnaire was only proposed in two languages (French and English) excluded women who did not have sufficient mastery of those languages.
Future studies should prospectively investigate the effect of specific elements of antenatal classes (format, content, setting, etc.) on the risk of PTSD-FC, ideally employing a randomised controlled trial design.

Conclusion
This study shows that women who attended antenatal classes had a poorer childbirth experience but were less likely to develop birth-related intrusion symptoms. Obstetric or neonatal outcomes were similar between both groups. The result related to the childbirth experience raises questions about the match between the content of the sessions, the reality of the needs and expectations of women, and the possibilities offered by the birth centres. It seems necessary to define which methods, contents, and tools would promote a better childbirth experience.

Data availability
The datasets used and/or analysed during the current study available from the corresponding author on reasonable request.