Antihistamines and Fertility: A Comprehensive Guide

Question
Hello,

We've actively been trying to conceive since January.  We are both 30.  I have cycles ranging from 25-31 days.  During the past 7 cycles we have used an ovulation predictor kit and I ovulate between days 10 and 17.  For the majority of these cycles we have had sex on the first day the kit tests positive, as well as the followng day.

With the basic information having been covered, here is my concern:  

I have horrible allergies and for the past 5 years have taken Flonase (one spray each nostril daily) and Allegra (60 mg once daily).  Two months ago I stopped taking Allegra and switched to Loratadine (OTC Claritin, 10 mg daily) because it is considered "safer" during pregnancy.  

I have read that antihistimines affect cervical mucous and so for the past two cycles have taken OTC Guaifenesin from day 12 through ovulation to help counteract this effect.

Without my daily medication I essentially have a constant bad sinus infection.  However, if it is somehow preventing me from getting pregnant I would give them up temporarily.

What is your recommendation?

Thank you,

Lydia

Answer
You do not have to stop your antihistamines because they do not prevent you from conceiving. YOu are doing the correct thing by improving your cervical mucus and you should not suffer through congestion and allergy symptoms. However, once you become pregnant, I would stop the histamines because they lower blood volume during the pregnancy. If you are having a 25-31 day cycle, then you probably ovulated between cycle day #11-17 (as you said). I would concentrate having sex every other day from cycle day #12-18. Good Luck.