Hope you can help

Jessica
Okay so me and my husband can have sex all year and only 2 months out of the year i can fall pregnant why is that!! I have three kids two born in February and one in march so that means may and June are the only months I can fall pregnant!! All the other 10 months we can have sex every day and still don't fall pregnant!! Is it me or is it him dose anyone know why this is thank u