BioPRYN and twins

We've been using BioPRYN to diagnose pregnancies for quite a while now. We like the convenience and the ability to preg check cows as soon as they reach 35 days post-breeding. We love our vet, but it just isn't feasible for us to have herd health visits every two weeks. Before we switched to BioPRYN, we did pregnancy exams by ultrasound once a month. That meant some cows were over 60 days post-breeding before we found out if they'd settled or not. With BioPRYN, we know if a cow is open or pregnant before she hits 42 days post-breeding; if she's open we can then watch for her 42-day heat. We feel this has played a role in helping us reach and exceed our pregnancy rate goal of 20%; we're now running a 24% pregnancy rate.

We still have our vet out to ultrasound cows on occasion, usually if the cow has been a problem breeder in the past and we want double confirmation or if the cow experienced a fever as part of an illness and we think her fetus may have been affected. Now, we're thinking of adding another reason – twins.

Believe it or not, these guys are twins. They were our very first set.

One of our cows, Dinky, has a history of twinning. When she was confirmed pregnant by BioPRYN this lactation, the level of Pregnancy-Specific Protein B came came back quite a bit higher than the other cows in that sample group. One month later she was in heat again so we started to wonder if maybe she had been pregnant with twins – a common reason for pregnancy loss.

Last week Dinky was confirmed pregnant again; the level of PSPB was about double this time as well. We're planning to have Doc check her for twins, but in the meantime we have some questions. Has anyone else found a correlation between high PSPB numbers and twin pregnancies? Does anyone else follow-up after a BioPRYN test with an ultrasound exam? If so, what have you learned?