Fear of childbirth and use of labor analgesia: A nationwide register‐based analysis in Finland

To calculate the rates of labor analgesia among women with fear of childbirth (FOC) in multiparous and nulliparous women, because FOC might be associated with higher rates of labor analgesia.

studies have reported the rates of different labor analgesia among these women. A new study in 2021 found that FOC is a potential predictor of higher labor pain intensity. 15 In addition, the study concluded that analgesic consumption was not proven to be associated with FOC. 15 A study in 2018 found that women with severe FOC experienced more labor pain than women without FOC, but adjusting the symptoms by maternal depression, anxiety, and use of epidural/ spinal anesthetic or nitrous oxide gas, there was no evidence of a difference. 16 Based on our hypothesis, due to the increased intensity of pain during labor, and higher desire for pain relief by the mother, FOC might be associated with higher rates of labor analgesia. This study aims to calculate the rates of labor analgesia among women with FOC in multiparous and nulliparous women, when compared with those without FOC diagnosis.

| MATERIAL S AND ME THODS
In this nationwide retrospective register-based cohort study, data from the National Medical Birth Register (MBR) was used to evaluate the use of labor analgesia in pregnancies with FOC, when compared with the pregnancies without. The MBR contains information on pregnancies, delivery statistics, and the perinatal outcomes of all births with a birth weight of 500 g or more or a gestational age of 22 +0 weeks or longer, and it is maintained by the Finnish Institute for Health and Welfare. The MBR has high coverage and quality (the current coverage is nearly 100%). 17 The study covered the period  Our main outcome in this study was the use of labor analgesia. The analgesia methods were stratified into neuraxial analgesia (epidural, spinal, and combined), pudendal, paracervical, nitrous F I G U R E 1 Flowchart of the study groups. Pregnancies with diagnosed maternal fear of childbirth were compared with those without it.
oxide, other medical (includes opiates), other non-medical (such as bath, aqua bubbles, and transcutaneous electrical nerve stimulation), and no analgesia. These are analyzed as categorized dichotomy (yes or no) variables, because the register does not contain more precise information, for example on the dosage used. The register only gathers information on intrapartum analgesia excluding analgesia used during CS or other surgical procedures. One patient may have had none or many of these during labor. Continuous variables were reported as mean with standard deviation or as median with interquartile range based on the distribution of the data.
Categorized variables were presented as absolute numbers and percentages. An α of 0.05 is used as the cut-off for significance.
The results of this study are reported according to the STROBE guidelines. 18

| RE SULTS
A total of 19 285 pregnancies with diagnosed maternal FOC were found during our study period. Of these, 6144 (31.9%) pregnancies were first pregnancies ending in delivery for the mother. The control group consisted of a total of 757 997 pregnancies without diagnosed maternal FOC. Of these, a total of 321 307 (42.4%) pregnancies were first pregnancies for the mother. Women with FOC had a higher rate for gestational diabetes (17.0% vs 12.5%), labor induction (34.1% vs 21.5%), and urgent CS (19.0% vs 10.0%). Background information on the study groups is shown in Table 1.

| DISCUSS ION
The main finding in this study was that women with diagnosed FOC had a higher rate of labor analgesia, especially neuraxial analgesia (epidural, spinal, combined spinal-epidural), and pudendal block.
Most importantly, a notable increase in the use of epidural analgesia was observed, especially among multiparous women.
In multiparous women, the rate of epidural analgesia was nearly two times higher among women with diagnosed FOC than women without FOC. This is a new finding, as the previous study focusing on the use of epidural analgesia did not observe any evidence of a difference in the use of labor analgesia among women with FOC and those without FOC. 15 This study did not analyze multiparous and nulliparous women separately. In previous studies, FOC has been associated with higher intensity of pain during labor, 15  intensity of the pain and therefore increase the desire for pain relief in subsequent pregnancies. Confounding factors, such as higher body mass index among women with FOC might partly explain the higher rate. 19 However, according to a recent study in Finland, women with gestational diabetes (which was much more prevalent among women with FOC) had no higher rate of labor analgesia. 20 Among women with FOC, higher rates of spinal analgesia and pudendal block compared with women without FOC may reflect the fear of pain, especially during the active second stage of labor. In addition, the notably higher rate of labor inductions most likely partly explains the increased rate of epidural analgesia.
As the prevalence of FOC is currently rapidly increasing, 3 studies assessing this topic are warranted. In addition, as the range of symptoms caused by FOC was recently found to be higher than thought, including lower birth rate and psychological challenges, 9,10 the studies should focus on the optimal treatment of patients with FOC, and prevent the development of FOC for women without a diagnosis FOC. The results of this study should be acknowledged by the clinicians and anesthesiologists to improve satisfaction levels and to provide optimal treatment for mothers with FOC.
The main strength of the present study is the nationwide register coverage including practically all deliveries in Finland and the high validity and precision of the register. 17 The main limitation is the lack of data on attempted analgesia methods, as only successful analgesia methods are reported to the register. Another limitation is that the register does not have information on analgesic doses and therefore possible differences between the two groups remain unknown. the size of the non-exposed group was large, the possible bias of undiagnosed FOC patients should not have a major impact on results.
Possible unidentified cases of FOC in the non-exposed group would most likely lead to results that are biased towards the null.
The main finding of this study was that women with diagnosed FOC had a higher rate of labor analgesia. Most importantly, a notable increase in the use of epidural analgesia was observed, especially among multiparous women. The results of this study can be used by midwives, obstetricians, and anesthesiologists to prepare and provide optimal pain relief for mothers with FOC.

AUTH O R CO NTR I B UTI O N S
MV wrote the initial manuscript. IK, VMM, and MV undertook the study design. MK provided clinical expertise. Each author commented on the manuscript during the process and confirmed the final version to be submitted.

CO N FLI C T O F I NTE R E S T S TATE M E NT
The authors declare no conflict of interest.

DATA AVA I L A B I L I T Y S TAT E M E N T
Research data are not shared.