Effects of a New Mattress and Pillow and Standard Treatment for Nightly Pelvic Girdle Pain in Pregnant Women: A Randomised Controlled Study

Figures & data

Figure 1 The mattress and pillow. Image courtesy from Dr Hasse Ejnell.

Table 1 Baseline Characteristics of the Study Groups

Variables		Intervention Group	Control Group
		n=34	n=32
Maternal age (years)		31.4 (3.9)	30.8 (4.8)
Education
Primary School		3 (9)	3 (9)
High School		8 (23)	6 (19)
University		18 (53)	16 (50)
Other		5 (15)	7 (22)
Nulliparous women		13 (38)	12 (38)
Gestational age (week)		22.6 (5.5)	21.9 (5.2)
BMI at inclusion		27.1 (3.7)	26.2 (4.3)
Use of analgesics*		9 (26)	6 (19)
Pain provocation tests for anterior pain
Modified Trendelenburg test		24 (71)	20 (63)
MAT-test		24 (71)	26 (81)
Pain provocation tests for posterior pain
Modified Trendelenburg test		27 (79)	24 (75)
PPPP-test		33 (97)	28 (88)
Patrick’s Faber test		28 (82)	27 (84)
Functional test
ASLR- test (0–10)		4.9 (3.1)	4.3 (3.2)
Primary outcomes
Nightly anterior pain, VAS, 0–100 mm		44.3 (26.1)	46.5 (25.4)
Nightly posterior pain, VAS		61.2 (16.9)	60.4 (21.5)
Secondary outcomes
Evening anterior pain, VAS		45.9 (27.3)	51.2 (26.9)
Evening posterior pain, VAS		60.9 (17.6)	65.0 (20.9)
ESS		12.0 [7;16]	10.5 [8;13]
EQ-VAS		50.0 [30;60]	46.5 [34;65]
Nightly wake ups		3.9 (2.1)	3.2 (1.6)
PCS, total score		24.5 [17;34]	28.0 [19;36]
PGQ		52.5 [47;58]	49.0 [42;57]
Sleep duration, minutes		360 (85.2)	359 (78.0)
Women on sick leave		16 (47%)	15 (47)

Notes: Values are given as n (%), mean (SD) or median [25 to 75 quartiles] when appropriate. All p-values not significant. *Paracetamol. Intervention group, Standard treatment plus mattress and pillow, Control group, Standard treatment.

Abbreviations: ASLR-test, active straight leg test; BMI, body mass index; ESS, Epworth sleepiness scale; EQ-VAS, euroqol visual analogue scale; PGQ, pelvic girdle questionnaire; PCS, pain catastrophizing scale; PPPP-test, posterior pelvic pain provocation test; VAS, visual analogue scale: 0 to 100 mm.

Figure 2 Participants’ progress through trial and withdrawals.

Table 2 Differences in Primary and Secondary Outcomes from the Baseline to the Fourth Treatment Week. Analysis is per Protocol

	Intervention Group (n= 19)		Control Group (n = 25)		Between-Group Change Comparison
	Within-Group Change Between Baseline to 4-Weeks	P-value	Within-Group Change Between Baseline to 4-Weeks	P-value	Mean Difference with 95% CI	P-value
Primary outcome
Nightly posterior pain, VAS^a	−14.9 (29.4) [−34.3;0.3] −11.3 {76.6;40.0}	0.033	1.6 (20.2) [−2.1;10.7] 4.0 {-63.3;31.0}	0.34	16.5 [1.4;31.6]	0.028
Secondary outcomes
Nightly anterior pain, VAS^a	−8.4 (27.3) [−20.1;12.3] −1.4 {-72.7; 33.4}	0.26	2.6 (11.7) [−4.5;12.9] 0.8 {-26.4; 24.7}	0.24	11.0 [−1.3;23.2]	0.28
Evening anterior pain, VAS^a	−5.5 (24.0) [−22.0;11.7] −1.6 {-71.1;25.7}	0.52	2.8 (16.1) [−4.3;8.9] 2.2 {-27.9;40.7}	0. 35	8.3 [−4.0;20.5]	0.43
Evening posterior pain, VAS^a	−14.4 (22.1) [−21.7;0.2] −7.8 {-81.6;12.0}	0.008	−3.2 (21.2) [−14.0;9.3] −0.5 {-66.2;34.0}	0.72	11.2 [−2.1;24.5]	0.066
Women on sick leave^b	1 (5.3%)	1.00	0 (0%)	1.00		0.71
Sleep duration, minutes^a	25.6 (71.8) [8.6;68.6] 25.7 {-205.7;111.4}	0.022	13.8 (25.1) [0.0;34.3] 8.1 {-30.9;60.0}	0.014	−11.8 [−43.5;19.9]	0.046
Nightly wake ups^a	−1.1 (1.9) [−2.2;0.6] −0.7 {-4.6;1.6}	0.049	−0.2 (0.8) [−0.8;0.3] −0.2 {-1.5;1.2}	0.29	0.9 [0.07;1.8]	0.15
PGQ^a	1.0 (8.2) [−4.0;7.0] 2.0 {-17;16}	0.48	4.5 (8.2) [−1.0;8.0] 3.0 {-8;25}	0.018	3.6 [−1.5;8.7]	0.33
EQ-VAS^a	4.5 (20.7) [−8.0;20.0] 2.5 {-30;47}	0.36	−2.0 (17.2) [−4.0;2.0] 0.0 {-49;37}	0.67	−6.5 [−18.0;5.0]	0.36
ESS^a	−0.1 (3.1) [−3.0;3.0] 0.0 {-5;6}	0.81	1.0 (1.9) [0.0;2.0] 1.0 {-2;5}	0.021	1.1 [−0.4;2.6]	0.20
PCS, total score^a	−6.4 (8.6) [−14.0;-2.0] −5.0 {-22;10}	0.005	−3.0 (5.7) [−5.0;0.0] −3.0 {-15;13}	0.010	3.3 [−1.1;7.7]	0.20

Notes: For categorical variables n (%) is presented; For continuous variables Mean (SD) [95% CI] Median {Min-Max} is presented; ^ap-values between groups from Mann–Whitney U-test and within group from Wilcoxon Signed rank test; ^bp-values between groups from Fishers Exact test and within groups from Sign test.

Abbreviations: ESS, Epworth sleepiness scale; EQ-VAS, European quality of life measure visual analogue scale; PCS, pain catastrophizing scale; PGQ, pelvic girdle questionnaire; VAS, visual analogue scale.