Pregnancy is associated with a increased risk of developing blood clots. There is nearly a 5 times greater risk of developing a blood clot in pregnancy. Lovenox is a medication that helps to prevent the body from developing clots. It is safe to use in pregnancy. Previous studies have demonstrated that despite recommendation of Lovenox, to prevent blood clots, the majority of patient's (70 to 90%) did not receive adequate levels of Lovenox at times throughout the day, which likely increases the risk of developing clots. The increase in blood volume and increase in kidney function that occurs in pregnancy may contribute to the inadequate levels. Currently the recommendation for pregnant and nonpregnant patients requiring Lovenox, is to calculate the daily dose of Lovenox and split the dose, giving half in the morning and the other half in the evening. This research study proposes that due to changes in the body during pregnancy that the daily Lovenox dosing be split into three times a day to achieve more consistent levels of Lovenox than twice a day in pregnant women.

Inclusion Criteria:

• Nulliparous or multiparous women with single intrauterine pregnancies who require therapeutic low molecular weight heparin during their pregnancy.
• Participants must be age 18 or older.

Exclusion Criteria:

• Women with multiples.
• Women less than age 18
• History of Heparin Induced Thrombocytopenia (HIT)
• Allergy to enoxaparin