When they allegedly married, February of '61, She was already 18. She was born November 29, 1942, so she was not much under 18 when she got knocked up. BHO born Aug 4, '61. go back 38 weeks, (2 weeks after last period) you get to about November 11th. Could be as early as late October, or as late as about November 20. She would not have "been late" until about The first of December.
Could have made finals a bit trying. But she'd have been 18 by the time she suspected she was pregnant, unless Barry was a really late birth. Remember this was '60-'61, no EPT in those days, and even the tests at the doctor's office didn't work too early on.
OTOH, in those days, finals were often not until mid January, for schools on the semester system, which U. HI was. If she took them at all, finals would have been definitely challenging due to "other distractions". I suspect she did take them, and blew most of them, grades for last few weeks of the semester might not have been too great either. Or she might just have partied hearty all semester.
Married in Feb....traveling on a boat...Jan, mid-Dec? How long does it take a boat to get from HI to Kenya. Kenya was on the “Spice Route”, cloves. Could they have gotten a cabin on one of the “cargo ships”? Get married when they get to Kenya in February.....