(entertainmentwise.com) - Beyonce and Jay-Z have reportedly hit a rocky patch in their four-month marriage - because the Bootylicious star wants to put her career before starting a family.The couple tied the knot in a hush-hush ceremony on April 4, amid rumours that Beyonce was already expecting."Jay Z is ready to have children. He [and Beyonce] dated for years, now they're married...and for him - it's time for children," a source close Jay-Z rapper told MediaTakeOut.But it seems that motherhood isn't part of the singer's immediate plans."Beyonce is very career focused. She has another album due this year and a couple of major film projects in the works," the source continues. "Her career is moving at 90 miles per hour and she's not trying to have it slowed down by a baby."[Jay Z and Beyonce] are best friends so it's not like they're fighting over it...but they both feel very strongly about [their positions] - if one of them doesn't relent, I think it could be a big problem."