PAPP-A as a screening tool for assessment of gestational age before medication abortion in an intended-use population.

In the USA, abortion with pills is an option for people with pregnancies of less than 71 days. Usually, people use ultrasound to find out how far along a pregnancy is. Ultrasound can be pricey and hard to find. Some studies show that a protein in blood, called PAPP-A, may be another option. The authors took blood from and did ultrasounds for people who wanted an abortion. They measured how much PAPP-A was in the blood using two different methods. The level of PAPP-A in the blood did a good job of distinguishing pregnancies that were higher and lower than 71 days.