Participants
Data were collected at the antenatal clinic of Chaohu Hospital of Anhui Medical University from September to December 2019. The hospital is a comprehensive tertiary hospital, providing medical services to approximately one million people. The inclusion criteria were as follows: 1) participants were primigravida; 2) pregnant women aged 18-45 years; 3) women with a gestational age of 28-40 weeks; and 4) women with singleton gestation. The exclusion criteria were as follows: 1) women with a previous history of mental illness; 2) women with a high-risk pregnancy (gestational diabetes, hypertension and preeclampsia); 3) women have a history of miscarriage. We administered 280 questionnaires and finally analyzed 260 questionnaires after excluding incomplete and invalid questionnaires. The sample recovery rate was 92.86%.
Procedures
The ethics committee of Chaohu Hospital of Anhui Medical University approved the study protocol. The procedures used in this study adhered to the principles of the Declaration of Helsinki. All the women signed informed consent forms. The evaluation and screening of all scales were completed by two nurses and three uniformly trained graduate students, and standardized instructions were given to all participants before the start of the research.
Measures
Demographic characteristics
We used a self-designed questionnaire to collect demographic characteristic data, including age, gestational age, education level, planned pregnancy, prenatal education, working status, exercise, and marital satisfaction of pregnant women enrolled in our study.
Prenatal depression
The Edinburgh Postpartum Depression Scale (EPDS)[25] was chosen to assess the participants’ severity of depression. The EPDS can be used to screen for postpartum depression as well as depression during pregnancy. The EPDS contains a total of 10 items. The total score ranges from 0 to 30, and the higher the score is, the more serious the degree of depression. The content validity ratio is 0.93. The α coefficient is 0.76. We regarded a total EPDS score ≥12 as being indicative of diagnosing maternal depression. This scale has been verified in different cultures[26-28]. Furthermore, this scale has been proved and practiced frequently in China[29, 30].
Attachment
Attachment in all pregnant women was assessed with the Experience of Close Relationship (ECR) scale[31], which demonstrated high measurement accuracy[32]. The scale consists of 36 items, each ranging from 0 “strongly disagree” to 7 “strongly agree”. The scale has two dimensions: anxiety and avoidance. The avoidance subscale includes 18 items, indicating the avoidance of intimacy and interdependence. The anxiety subscale also includes 18 items and indicates concerns about exclusion and abandonment. According to the score of the two dimensions, attachment can be divided into secure and insecure attachment, in which there are three types in insecure styles (attentive, indifferent and phobic).
MAAS
The Maternal Antenatal Attachment Scale (MAAS) [33]was used to assess the MFA of the participants. The MAAS is a self-reported scale that includes 19 questions with a 5-point scoring system, and the total score of MFA ranges from 5 to 95, with higher score signifying higher MFA[34]. The scale includes two sub-dimensions: “MFA quality” (items 3, 6, 9, 10, 11, 12, 13, 15, 16, and 19) and “MFA intensity” (items 1, 2,
4, 5, 8, 14, 17, and 18). The item 7 is only included in the total score and does not affect any of these two dimensions. MFA quality indicates the emotional experience with regard to the fetus, and MFA intensity indicates the time and energy devoted to the fetus by the pregnant women.
Data analysis
We used the Statistical Package for Social Sciences (IBM SPSS 22.0) for all analyses conducted in this study. The continuous variables were tested by t-test or Mann-Whitney U test according to whether they obeyed the normal distribution, and the chi-square test was used to classify the variables. Before the mediation analysis, Spearman's correlation was calculated to determine the correlations between attachment anxiety or avoidance, the maternal depression score, and MFA. Finally, we found pairwise correlations between anxiety/avoidance, the depression score, and MFA quality. Subsequently, model 4 of Hayes’s (2013) PROCESS macro and Bootstrap were used to analyze the mediating effect. The model estimates the direct effect of anxiety/avoidance on maternal depression and maternal depression on MFA, the indirect effect of attachment anxiety/avoidance on MFA mediated by maternal depression as well as the direct effect of on MFA. A p-value of 0.05 was considered to be statistically significant.