Table 1.

Outcomes

Primary efficacy outcome	Live birth (defined as birth of a living child)
Principal safety outcome	Clinically relevant bleeding (that is major bleeding and clinically relevant non-major bleeding)
Secondary study outcomes
Efficacy	Ongoing pregnancy beyond 12 weeks’ gestation
	Preeclampsiaab
	HELLP syndromeac
	Intrauterine growth restrictionad
	Placental abruptionae
	Premature birthaf
	Intra-uterine fetal deatha
	Major congenital anomaliesag
	Composite of confirmed deep vein thrombosis and confirmed pulmonary embolismh
Safety	Post-partum bleeding and severe post-partum bleeding
	Major bleeding
	Clinically relevant non-major bleeding
	Minor bleeding, including increased tendency to bruising not fulfilling the criteria for clinically relevant non-major bleeding
	Heparin-induced thrombocytopenia (defined according to ACCP criteria [24])
	Allergic reactions (redness or itching) localized at the injection site of LMWH
	Type 1 allergy: e.g. generalized symptoms including anaphylaxis

^aDenominator for these outcomes is ongoing pregnancies beyond 12 weeks’ gestation.

^bPreeclampsia is defined as hypertension (systolic blood pressure ≥ 140 mmHg and/or diastolic blood pressure ≥ 90 mmHg after 20 weeks’ gestation, measured twice in a previously normotensive woman) with new-onset proteinuria at or beyond 20 weeks’ gestation.

^cHELLP syndrome is defined as a platelet count less than 100 * 10⁹/L and aspartate aminotransferase of 70 U/L or greater and lactate dehydrogenase of 600 U/L or greater.

^dIntra uterine growth restriction is defined as birth weight < 10th percentile for gestational age.

^ePlacental abruption (also known as abruptio placentae) is a complication of pregnancy, wherein the placental lining has separated from the uterus of the mother. Diagnosis according to clinical criteria (vaginal bleeding and uterine tenderness in combination with fetal distress necessitating prompt delivery) and examination of the placenta.

^fPremature birth is defined as birth < 37 weeks’ gestation.

^gMajor physical anomalies are defined as physical anomalies that have cosmetic or functional significance.

^hDeep vein thrombosis and pulmonary embolism are defined as abnormal compression ultrasound or an intraluminal filling defect on venography (deep vein thrombosis), or an intraluminal filling defect on spiral computed tomography (CT) scan, cut-off of vessels more than 2.5 mm in diameter on pulmonary angiogram or a perfusion defect of at least 75% of a segment with a local normal ventilation result (high-probability) on ventilation/perfusion lung scan (pulmonary embolism).

Criteria for bleeding are listed in Table 2.

ACCP, American College of Chest Physicians; LMWH, low-molecular-weight heparin.