Prevalence and Associated Factors of PostTraumatic Stress Disorder (PTSD) Among a Cohort of Post-Partum Sri Lankan women: A Cross Sectional Study

A cross-sectional study was conducted in eld clinics of a semi-urban area. A pre-tested interviewer administered checklist was used to collect socio-demographic and pregnancy related data. Pre-existing self-administered, validated Sinhalese versions of the Edinburgh Postnatal Depression Scale (EPDS) and PTSD Symptom Scale-Self Report (PSS-SR) were used to assess the presence of Post-Partum Depression (PPD) and PTSD, respectively. Each participant was assessed at one, two and six months after the delivery for PTSD and PPD. Scores of PPD >9 and PSS-SR >13 were taken as positive for the two conditions, respectively.

Background "Stress" is de ned as a response of oneself to a change in the environment, which may be adaptive or non-adaptive. A normal stress response is adaptive and bene cial. Nevertheless, non-adaptive stress responses like Post Traumatic Stress Disorder (PTSD) can impair normal functionality (1).
Affected individuals of PTSD present with a characteristic triad of re-experiencing the symptoms ( ashbacks, nightmares), avoidance of symptoms (staying away from reminders) (2) and symptoms of arousal/reactivity developing over few weeks to several months after exposure, in the absence of an organic cause. PTSD usually occurs in people who have experienced an exceptionally shocking, threatening or catastrophic event.
Birthing is a positive experience for most women; however, it can be daunting in a minority of them.
Traumatic child birth is a recognized risk factor for developing postpartum PTSD (3). Therefore, it is postulated that intense physical and mental stressors associated with child birth lead to PTSD in the postpartum period in some pregnant women. Furthermore, PTSD is a condition associated with Post-Partum Depression (PPD), violence, suicide (3), as well as relationship problems (1) and fertility issues (4). If not detected, it puts both the mother and newborn at risk. As early identi cation and intervention will minimize the risk to the mother and newborn, it is imperative that both obstetric and mental health caregivers promptly recognize this subset of mothers who develop postpartum PTSD.
Currently, routine screening is being done for postpartum depression (PPD) successfully in postpartum clinics. However, in the recent past, there is a growing concern amongst the medical profession that some mothers having PTSD are being misdiagnosed and labelled to be having PPD. This can lead to detrimental outcomes for mothers with PTSD as the management of PTSD is different to that of PPD (5).
Postpartum PTSD had been a subject of extensive study worldwide with a global prevalence of 3.17% (6).
However, published data is very limited within the South Asian region. Therefore, it is important to determine the hidden burden of PTSD and the factors associated with it in order to take necessary remedial actions.
Accordingly, this study was conducted with a view of describing the prevalence and associated factors of Post Traumatic Stress Disorder among a cohort of postpartum mothers.

Methods
A cross sectional study at three different points of time, with an analytical component, was conducted at four randomly selected eld clinics located in the Horana MOH area. Two hundred and twenty-ve postpartum mothers after their rst month of delivery, who had no previous diagnosis of a psychiatric illness were included in the study.
Data collection was done using an interviewer administered checklist for socio-demographic data, and a Sinhalese validated self-administered questionnaire, the PTSD Symptom Scale-Self Report: PSS-SR (7) to assess PTSD symptoms, and the Sinhalese validated self-administered Edinburgh Postpartum Depression Screening Scale: PDSS (8) to assess the postpartum depression. Both of these questionnaires have been used in similar studies in Sri Lanka (7,8). Postpartum PTSD was taken as a PSS-SR score > 13. Follow up of the same individuals during their second and sixth months postpartum was done, where they were repeatedly offered the self-administered questionnaires of the PSS-SR scale and EPDS scale.
A pilot study was conducted in a polyclinic in the Horana MOH area which is not included in the study, to assess the practicality and feasibility in carrying out the data collection.
Ethical clearance was obtained from the Ethical Review Committee of the Faculty of Medicine, University of Colombo (Ref No:EC-16-169). The information sheet was explained to each participant and verbal consent was obtained.
Verbal consent was deemed more appropriate by the Ethical Review Committee, since a government-led mandatory post-natal screening (using EPDS) was already in place in the same clinics, for which verbal consent alone was being taken.
This similar non-interventional study has no more than minimal risks to its subjects, making verbal consent su cient for this setting. In addition, the only record linking the subject to the study would be the consent form, therefore, in order to protect the anonymity of the subjects, verbal consent was taken.
Statistical analysis was performed using the SPSS statistical package version 18.

Results
Two hundred and twenty-ve mothers at one-month post-partum were included in the study. Out of them 214 and 211 were re-evaluated at the second and sixth months post-partum. The attrition was very less since 93.8% (n = 211) of the post-partum mothers participated at the end of the sixth month as well. The mean age of the mothers is 28.38 years (SD = 5.52), while the median age is 28 years with a minimum of 15 years and maximum of 42 years. Among the participants of the study, 40.9% (n = 92) had an education level above the GCE ordinary level (O/L).
The prevalence of PPD among the study participants was 7.1% (n = 16), 4.2% (n = 9) and 0.9% (n = 2) at the rst, second and sixth month postpartum, respectively. Altogether 24 (10.4%) had developed PTSD following delivery up to 6 months. Figure 1 summarizes the prevalence of PTSD during the study period.

Factors Associated With Postpartum Ptsd
Pre-pregnancy factors Table 1 depicts the association between postpartum PTSD and pre-pregnancy factors; family history of mental illness, level of education of the mother and intimate partner violence were not signi cantly associated with postpartum PTSD.  Table 2 describes the antenatal factors associated with postpartum PTSD. None of the factors below were signi cantly associated with the development of postpartum PTSD.  Table 3 describes the association of antenatal factors with postpartum PTSD. Verbal abuse in labour was signi cantly associated with postpartum PTSD.

Discussion
In this study, the prevalence of PTSD at one, two and six months postpartum, was 2.7% (n = 6), 0.9% (n = 2) and 0.5% (n = 1), respectively and the overall prevalence was 3.6%. These are comparable to the prevalence rates of most of the studies done in other countries. Several cross-sectional studies, including those conducted in Iran and Nigeria, have found that the prevalence of postpartum PTSD after one month of delivery was in the range of 1.2-9.4% (4). A meta-analysis including 50 studies (N = 21, 429) from 15 countries studying PTSD symptoms in postpartum mothers showed a global prevalence of 3.17% at one month postpartum, which is compatible with the ndings of this study (6).
A Serbian study which was conducted using a scale which is different to the tool used in this study, the Clinician-Administered PTSD Scale (CAPS), also supports similar rates of postpartum PTSD at the rst month which was 2.4% (10). However, the same study found that 9.5% of the mothers had a clinically signi cant level of disabling PTSD symptoms (partial PTSD), which was not amounting to the full disorder. Moreover, at the second and the third months postpartum, the prevalence of partial PTSD 5.9% and 1.3%, respectively, while none of the participants had full PTSD (10). Symptoms of partial PTSD were not analyzed in our study, as the validated tool used did not categorize them speci cally. However, the pattern found in the Serbian study is similar to our study, as rates of full PTSD was seen to follow a declining trend with time (at two and six months, prevalence of PTSD being 0.9% and 0.5%, respectively) suggesting a probable self-limiting natural course of the condition over time.
Various studies have found different prevalence rates. A two staged study conducted in the USA, using the same tool used in this study, the PTSD Symptom Scale-Self Report (PSS-SR), found a higher prevalence of postpartum PTSD of 9% after 1 month, while 18% experienced high levels of post-traumatic symptoms (partial postpartum PTSD) (9). Another cross sectional study done in a fetal high-risk maternity hospital in the city of Rio de Janeiro, Brazil, using a different tool, the "Stress Disorder Checklist; PCL-C", found a higher prevalence (9.4%) of post-partum PTSD (10). Socio-cultural differences between the two countries may have played a role in these observed differences of prevalence. The study done in Brazil included a selected high-risk population for postpartum PTSD (mothers with pregnancy complications and high fetal risk).
Some studies demonstrate a lower prevalence compared to this study. A Dutch study (11) involving 428 women shows a prevalence of 1.2%. A Swedish study of 1640 postpartum mothers, that used the Traumatic Event Scale (TES), shows a prevalence of PTSD of 1.7%. (12). Socio-cultural factors, levels of obstetric care and the usage of different scales may play a role in these observed differences.
In our study, only two signi cant associations with postpartum PTSD were demonstrate; Verbal abuse during labour (p = 0.04) and presence of Postpartum Depression (PPD) (P = < 0.001). There are several studies and a meta-analysis in favor of the presence of PPD being a well-documented risk factor for postpartum PTSD (5)(6)(7)12). In contrast, very few studies had speci cally looked into the effect of verbal abuse during labour on the development of PTSD (4).
According to studies worldwide, several factors associated with the development of PTSD following childbirth have been identi ed. Among the known pre-pregnancy associated factors, low educational level (14), unplanned pregnancy (9),fear of child birth (6), family history of mental disease (6), nulliparity (12) or three or more previous births (10) were not found to be signi cantly associated with postpartum PTSD in our study.
Intra-pregnancy factors associated with postpartum PTSD include gestational age at delivery (14), number of antenatal care visits (14), poor health or complications in pregnancy (6), hospital admission due to pregnancy complications [OR 11.86 (95% CI: 6.36-22.10)] (15), increased fear of childbirth (10), higher expected intensity of pain (10) and intimate partner violence (10). However, none of these factors showed a signi cant association with postpartum PTSD in our study.
Among documented postpartum factors found to be associated with postpartum PTSD are poor neonatal outcome (10), low neonatal APGAR Score at delivery (7), neonatal and maternal intensive care (5), birth defects (4), lack of support from family and partner (6,9), postpartum physical problems (9), lack of exclusive breast feeding at one month (9) and not having an opportunity to discuss concerns with health care staff about mental wellbeing (9). In our study, none of these associations reached the level of signi cance. Possible reasons for the lack of association may be the total sample size and number of mothers with postpartum PTSD being lesser than expected.
Being a small sample size, there is a limitation in generalizing these results to the entire population of the country where social and economic backgrounds might differ. Since this is a cross sectional study, it is di cult to establish the exact temporal relationships between the associated factors (e.g. when PPD and PTSD both present at the time of data collection, it is uncertain which developed earlier). Partial PTSD patients were not analyzed since the validated study instrument used did not speci cally categorize them.

Conclusions
PTSD is a postpartum psychiatric condition prevalent in this community, with an overall prevalence of 3.6% over 6 months. Verbal abuse during labour (p = 0.04) and presence of PPD (p = < 0.001) were signi cantly associated with the development of post-partum PTSD. There were no signi cant association between PTSD and education level of mothers, timing of delivery, gap between pregnancies, whether the pregnancy was pre-planned, history of subfertility, history of psychiatric disorders, intimate partner violence, number of antenatal hospital visits, type of hospital, mode of delivery, labour duration, physical abuse, presence of labour companion, mental trauma, postpartum hemorrhage, manual removal of placenta, negative birth experience, low neonatal APGAR score at delivery, receiving neonatal and maternal intensive care, birth defects, problems with breast feeding and opportunity to discuss problems with a health care worker.

Recommendations
There is an urgent requirement to provide awareness and training to the primary care health care staff on prompt identi cation of postpartum PTSD.
It is necessary to introduce a validated questionnaire to detect post-partum PTSD symptoms. A short questionnaire checking key symptoms of postpartum PTSD (like avoidance and ashbacks related to childbirth) would be helpful for rapid identi cation and prompt referral for management by a psychiatrist.
It is a feasible option since a similar screening method and referral pathway is already existent in screening for postpartum depression.