Table 1
Characteristics of included pregnancies.
| Pregnancies (n = 138) | |
|---|---|
| Maternal age in years [mean, SD] | 25.8 ± 3.8 |
| Nulliparous (n, %) | 82 (59.4%) |
| Acquired (Rheumatic) heart (n, %) | 134 (97.1%) |
| Mechanical (n, %) | |
| – Ball-and-cage – Tilting disc – Bi-leaflet | 7 (5.1%) 124 (89.9%) 7 (5.1%) |
| Site of mechanical valve (n, %) | |
| – Mitral – Aortic – Aortic and mitral (n, %) | 116 (84.1%) 3 (2.2%) 19 (13.7%) |
| Age at diagnosis of valvular disease, in years (mean, SD) | 14.2 ± 5.6 |
| Age at first valve replacement, in years (mean, SD) | 20.6 ± 4.5 |
| Interval between last valve replacement and conception, in years (mean, SD) | 5.2 ± 3.8 |
| New York Heart Association (NYHA) class at first visit (n, %) | |
| – I-II – III – IV | 109 (79.0%) 21 (15.2%) 8 (5.8%) |
| Other comorbidities (n, %) | |
| – Hypothyroidism – Anaemia – Seizure Disorder | 17 (12.3%) 13 (9.4%) 4 (2.9%) |
[i] SD = standard deviation, n, % = number and proportion.
Table 2
Details on anticoagulation regimens during pregnancy and the peripartum period (n = 138 pregnancies).
| Sequential treatment (n = 106) | VKA (n = 32) | |
|---|---|---|
| Anticoagulant used in first trimester | UFH (102, 96.2%) [Mean dose = 21,731 ± 5083 U] LMWH, Enoxaparin (4, 3.8%) [Mean dose = 65 ± 10 mg] | Warfarin (17, 53.1%) [Mean dose = 5.1 ± 1.6 mg] Acitrom (15, 46.9%) [Mean dose = 3.0 ± 0.7 mg] |
| Gestational age at bridging, in weeks’ gestation (mean, SD) | ||
| • From VKA to Heparin • From heparin to VKA | 6.3 ± 0.5 13.0 ± 1.0 | NA |
| Anticoagulant used in second/ early third trimester* | Warfarin (31/94, 33.0%) [Mean dose = 4.9 ± 2.1 mg] Acitrom (63/94, 67.0%) [Mean dose = 3.6 ± 1.1 mg] | Warfarin (12/27, 44.4%) [Mean dose = 5.4 ± 1.8 mg] Acitrom (15/27, 55.6%) [Mean dose = 3.3 ± 0.9 mg] |
| Gestational age at bridging from VKA to heparin, in weeks/ gestation (mean, SD) | 36.1 ± 1.3 | 36.5 ± 1.0 |
| Anticoagulant in third trimester ** | UFH (76/89, 85.4%) [Mean dose = 22,053 ± 4889U] LMWH, Enoxaparin (3/89, 3.5%) [Mean dose = 120 mg] Warfarin (5/89, 5.6%) [Mean dose = 6.7 ± 1.4 mg] Acitrom (5/89, 5.6%) [Mean dose = 2.8 ± 0.5 mg] | UFH (18/22, 81.8%) [Mean dose = 22778 ± 4142U] LMWH, Enoxaparin (1, 4.6%) [Mean dose = 80 mg] Acitrom (3, 13.6%) [Mean dose = 2.7 ± 0.6 mg] |
| Postpartum transition to VKA, in days (mean, SD) | 4.9 ± 1.2 | 4.5 ± 1.0 |
| Dose of VKA at discharge*** | Warfarin (36, 36.0%) [Mean dose = 5.7 ± 2.2 mg] Acitrom (64, 64.0%) [Mean dose = 3.3 ± 1.0 mg] | Warfarin (16, 50.0%) [Mean dose = 6.5 ± 1.8 mg] Acitrom (16, 50.0%) [Mean dose = 3.1 ± 0.8 mg] |
[i] LMWH = Low Molecular Weight Heparin; UFH = Unfractionated Heparin; VKA = Vitamin-K Antagonists; NA = not applicable; SD = standard deviation.
* After excluding those who had miscarriages and maternal death at <12 weeks of gestation.
** After excluding those who had miscarriage, preterm births and maternal death at less than 28 weeks’ gestation.
*** After excluding maternal deaths.
Table 3
Primary (Maternal) Outcomes.
| Sequential treatment (n = 106) | VKA (n = 32) | p value | |
|---|---|---|---|
| A. Maternal Death | 6 (5.7%) | 0 | 0.34 |
| B. Thromboembolic complications | 15 (14.2%) | 2 (6.3%) | 0.36 |
| C. Hemorrhagic complications – Antepartum haemorrhage – Atonic postpartum haemorrhage* – Surgical site haematoma* – Non-obstetric haematoma | 12 (11.3%) 3 5 5 perineal + 1 caesarean wound 1 | 4 (12.5%) 0 2 2 perineal 0 | 0.85 |
| D. Cardiac events | |||
| – Heart Failure – Arrhythmia | 4 (3.8%) 13 (12.3%) | 0 1 (3.1%) | 0.26 0.13 |
[i] VKA- Vitamin K antagonist.
* Excluding women who died undelivered(n = 2) and also those who had miscarriage (n = 20).
Table 4
Secondary Comparison of obstetrics and neonatal events and complications of pregnant women with mechanical heart valve on anticoagulation.
| Sequential treatment (n = 106) | VKA (n = 32) | p value | |
|---|---|---|---|
| Spontaneous miscarriage | 13 (12.3%) | 5 (15.6%) | 0.62 |
| Pregnancy termination | 0 (0) | 4 (12.5%) | <0.001 |
| Stillbirth# | 5 (5.4%) | 0 (0) | 0.58 |
| Neonatal death## | 1 (1.1%) | 2 (8.7%) | 0.11 |
| Congenital malformations – all – Warfarin embryopathy | 4 (3.8%) 0 (0) | 3 (9.4%) 2 (0.06%) | 0.35 |
| Birthweight in grams (mean, SD) | 2424.7 ± 591.5 | 2524.8 ± 668.5 | 0.48 |
| Fetal growth restriction# | 26 (28.0%) | 8 (34.8%) | 0.52 |
| Gestational age at delivery in weeks# (mean, SD) | 37.0 ± 3.0 | 36.6 ± 4.6 | 0.54 |
| Preterm birth# | 21 (22.6%) | 5 (21.7%) | 0.93 |
| Preeclampsia | 4 (4.5%) | 0 (0) | 0.58 |
| Gestational Diabetes Mellitus | 13 (12.3%) | 5 (15.6%) | 0.63 |
| Mode of delivery# | |||
| • Spontaneous vaginal delivery • Operative vaginal delivery • Caesarean delivery | 53 (57.0%) 20 (21.5%) 20 (21.5%) | 12 (52.2%) 8 (34.8%) 3 (13.0%) | 0.35 |
| Neonatal intensive care unit admission## | 16 (18.2%) | 5 (21.7%) | 0.70 |
| Maternal sepsis (puerperal or post-abortal) | 5 (4.8%) | 2 (6.3%) | 0.67 |
| Duration of maternal postpartum hospitalization (median, interquartile range) | 10 (8.5) | 10 (9) | 0.47 |
[i] VKA = vitamin-K antagonist, SD = standard deviation.
# Includes pregnancies that continued past 20 weeks.
## Excludes spontaneous miscarriages, pregnancy terminations and stillbirth.