 The protocol is altered for women who have an ultrasound that shows only a gestational sac no yolk sac or fetal pole. Women in both follow-up groups will have β-hCG testing on the day of methotrexate injection and again in 8 days. If the level does not fall by 50 or they have concerning symptoms, they are asked to return to clinic for evaluation. If the β-hCG level falls by 50 or more, they will continue to be followed as per the protocol in their chosen group, but will be followed until their β-hCG becomes negative. 