Timing of initiation of low-molecular-weight heparin administration in pregnant women with antiphospholipid syndrome: a randomized clinical trial of efficacy and safety

Figures & data

Figure 1 Study flow diagram.

Abbreviation: LMWH, low-molecular-weight heparin.

Table 1 Demographic characteristics and antiphospholipid antibodies status

	Early initiation group (n=48)	Later initiation group (n=46)	P-value
Age (years)a	27.77±3.72	28.28±4.32	0.539
BMIb	29.81 (22.94–32.77)	28.51 (20.80–32.79)	0.216
Gravidityb	6 (4–10)	5 (4–9)	0.115
Nulliparous womenc	21/48 (43.8%)	28/46 (60.9%)	0.105
Previous first trimester miscarriagesb	4 (3–8)	3 (3–7)	0.338
Women with previous second trimester miscarriagesc	8/48 (16.7%)	6/46 (13.0%)	0.774
Women with previous preterm laborc	4/48 (8.3%)	4/46 (8.7%)	1.000
Women with previous fetal lossc	8/48 (16.7%)	5/46 (10.9%)	0.553
Type of positive antiphospholipid antibodiesc
ACL IgM only	3/48 (6.3%)	2/46 (4.3%)	1.000
ACL IgG only	5/48 (10.4%)	7/46 (15.2%)	0.548
LAC only	22/48 (45.8%)	25/46 (54.3%)	0.536
ACL IgM and IgG	3/48 (6.3%)	2/46 (4.3%)	1.000
ACL IgM and LAC	4/48 (8.3%)	2/46 (4.3%)	0.678
ACL IgG and LAC	5/48 (10.4%)	5/46 (10.9%)	1.000
ACL IgM and IgG and LAC	6/48 (12.5%)	3/46 (6.5%)	0.487

a Notes: Expressed as mean ± SD and P-value was calculated by the t-test.

b Expressed as median and range and P-value was calculated by the Mann–Whitney U test.

c Expressed as frequency and percentage and P-value was calculated by the Fisher’s exact test.

Abbreviations: ACL, anticardiolipin; BMI, body mass index; IgG, immunoglobulin G; IgM, immunoglobulin M; LAC, lupus anticoagulant.

Table 2 Treatment characteristics and pregnancy outcomes

	Early initiation group (n=48)	Later initiation group (n=46)	P-value
Gestational age at start of treatment (weeks)a	4.57 (4.43–4.86)	6.71 (6.29–6.86)	<0.001
Compliance with LMWHa	96.67% (93.18%–100%)	98.46% (91.80%–100%)	0.199
First trimester bleedingb	8/48 (16.7%)	6/46 (13.0%)	0.774
Second trimester bleedingb	3/48 (6.3%)	5/46 (10.9%)	0.481
Clinical pregnancyb	47/48 (97.9%)	42/46 (91.3%)	0.199
Ongoing pregnancyb	39/48 (81.2%)	28/46 (60.9%)	0.040
First trimester miscarriageb	9/48 (18.8%)	18/46 (39.1%)	0.040
Second trimester miscarriageb	4/48 (8.3%)	2/46 (4.3%)	0.678
Gestational age at miscarriage (weeks)a	9.43 (6.86–22.57)	8.64 (6.43–21.29)	0.237
Fetal lossb	4/48 (8.3%)	2/46 (4.3%)	0.678
Live birthb	34/48 (70.8%)	26/46 (56.5%)	0.198

a Notes: Expressed as median and range and P-value was calculated by the Mann–Whitney U test.

b Expressed as frequency and percentage and P-value was calculated by the Fisher’s exact test. Bold P-values are statistically significant.

Abbreviation: LMWH, low-molecular-weight heparin.

Table 3 Characteristics and complications among pregnancies progressed beyond 24 weeks

	Early initiation group (n=35)	Later initiation group (n=26)	P-value
Gestational age at delivery (weeks)a	37.71 (28.57–39.14)	38.07 (29.14–39.29)	0.321
Delivery before 34 weeksb	5/35 (14.3%)	4/26 (15.4%)	1.000
IUFDb	1/35 (2.9%)	0/26 (0.0%)	1.000
IUGRb	7/35 (20.0%)	5/26 (19.2%)	1.000
Gestational hypertensionb	1/35 (2.9%)	2/26 (7.7%)	0.570
Preeclampsiab	8/35 (22.9%)	7/26 (26.9%)	0.770
Placental abruptionb	3/35 (8.6%)	1/26 (3.8%)	0.629

a Notes: Expressed as median and range and P-value was calculated by the Mann–Whitney U test.

b Expressed as frequency and percentage and P-value was calculated by the Fisher’s exact test.

Abbreviations: IUFD, intrauterine fetal death; IUGR, intrauterine growth restriction.

Table 4 Neonatal outcomes among live births

	Early initiation group (n=34)	Later initiation group (n=26)	P-value
Birth weight (g)a	2,950 (1,050–3,300)	2,950 (1,150–3,400)	0.535
Birth weight <1,500 gb	7/34 (20.6%)	6/26 (23.1%)	1.000
Birth weight <2,500 gb	9/34 (26.5%)	8/26 (30.8%)	0.777
Congenital malformationb	0/34 (0.0%)	0/26 (0.0%)	1.000
Neonatal RDSb	9/34 (26.5%)	8/26 (30.8%)	0.777
Admission to NICUb	11/34 (32.4%)	10/26 (38.5%)	0.785
Mechanical ventilationb	8/34 (23.5%)	6/26 (23.1%)	1.000
Early neonatal deathb	6/34 (17.6%)	4/26 (15.4%)	1.000

a Notes: Expressed as median and range and P-value was calculated by the Mann–Whitney U test.

b Expressed as frequency and percentage and P-value was calculated by the Fisher’s exact test.

Abbreviations: NICU, neonatal intensive care unit; RDS, respiratory distress syndrome.