Expert: Catherine Beier MS CBE - 1/17/2012

Question
Hi. My lmp was 9/7 or 9/8 2011. My cycles are around 31-34 days. My first question is about paternity. I had sex only twice that month. Once on 9/18, he pulled out and again on 9/26 he did not. I had an ultrasound in 11/9 which dated me at 8 weeks 2 days which points toward the second encounter. Is this correct? I really need to ease my mind. My due date from the transvaginal ultrasound is 6/18/12. Also, I have lost 6 pounds and im 18 weeks pregnant. Should I be worried? Thanks so much. I really appreciate your help.

Answer
Hello Mya,

Based on your information, you most likely conceived around 9/26.  Early transvaginal ultrasound is THE most accurate way to date a pregnancy and has a standard error of measure of +/- 1 day, so your original ultrasound was accurate about your conception date and that man #2 is the father without question.

The weight loss is common especially if you've had significant morning sickness.  Many women do not gain weight until into the second trimester.  The optimal weight gain if you are of normal weight pre-pregnancy is only 20-25 pounds for the entire pregnancy. Very often, women gain too much weight during pregnancy which can cause complications for both mother and baby.  You only need an extra 300 calories a day, which is the equivalent of an apple and a glass of milk.  So, as long as you are eating well and maintaining good nutrition, then the weight loss itself is not overly concerning.  If you are not able to keep food down or continue losing weight, then seek the advice of your care provider to ensure that you are maintaining adequate nutrition for yourself and your growing baby.


Best,
Catherine