What is your current level of practice in OB/GYN?
If you are a junior resident, then OBGYN MGMT, OBGYN News, Contemp OBGYN will give you great basic review articles, clinical pearls, research summaries.
If you are progressing through the ranks, then the Green (Obstetrics and Gynecology) and the Gray (Am Jrn of OB/GYN) are the most read. Journal of Repro Med is a good one too, but generally you get more bang for your buck (especially being over sees) with the former 2. If in Europe, definitely check out the BJOG!
As a fellow, it depends on your research focus. For me, DiabetesCare, Insulin, Obesity are a good adjunct to the above.
Good luck!