What is the most likely diagnosis for a patient who had preeclampsia diagnosed at 17 weeks in her prior pregnancy?

In this scenario, considering that the patient experienced preeclampsia at 17 weeks during her previous pregnancy, the most likely diagnosis now is chronic hypertension. Chronic hypertension is defined as elevated blood pressure that existed before pregnancy or that occurred before 20 weeks of gestation.

Since the patient was diagnosed with preeclampsia early in her last pregnancy, it suggests she may have underlying hypertension that was not previously identified or managed adequately. The early onset of preeclampsia in the previous pregnancy may indicate a predisposition to chronic hypertension. In contrast, gestational hypertension develops after 20 weeks of pregnancy and is not a pre-existing condition. Preeclampsia in a current pregnancy would typically occur again but considering her prior severe early onset, chronic hypertension is the most likely diagnosis as it reflects a continuous state rather than a new development.

Systemic lupus erythematosus, while it can influence blood pressure and is a potential risk factor for pregnancy complications, would require additional clinical evidence or symptoms for diagnosis. Thus, chronic hypertension is the most pertinent diagnosis given her obstetric history.