It comes after the Scottish Government warned of an expected dip in supply of Pfizer, which saw the number of doses administered in the final week of February drop to below a third of those given in the second week of the month.
Speaking to MSPs on Tuesday, Ms Sturgeon said the country could see a further supply dip next week.
But the First Minister maintained that vaccination targets will not be affected – including the aim to vaccinate all Scots over 50, unpaid carers, and those over 16 with underlying health conditions by mid-April.
Ms Sturgeon was questioned by Labour leader Anas Sarwar over the Scottish Government’s previous pledge to deliver 400,000 vaccinations a week once supplies allowed, a target which has not yet been hit.
“The Scottish Government has a target of 400,000 vaccinations a week, a target I have welcomed and support,” said Mr Sarwar.
“But the numbers for the last week in February show an average of around 29,000 vaccinations per day and yesterday fewer than 23,000 people were vaccinated.
“Today, the First Minister has suggested already there is the potential of slowing vaccination rates going forward even further.
“When will we have that target met of 400,000 vaccinations a week so we can collectively get out of this crisis?”
The highest weekly figure for vaccination so far was in the week from February 8 to February 14, when 392,178 first and second doses were given.
Ms Sturgeon said the dip in daily vaccination rates were “entirely down to supply”.
“If you look at numbers across the four nations you will see that same dip,” she said.
“We expect that there might be another dip in supply next week, we don’t expect that to affect the mid-April targets.”
The First Minister added that Scotland is now in a position to vaccinate the population “as fast as we have supplies”.
She said: “The constraining factor is supplies, and that is why we continue to talk regularly to the pharmaceutical companies to get as long term a line of site on their manufacturing and supply prospects, as we can.
"But we will vaccinate people just as fast as we have the vaccine to do it.”
Ms Sturgeon told parliament in early January that the Scottish Government aimed to deliver 400,000 vaccines a week from the end of February.
At that time the aim was also to give a first dose to all those over 65 and those with underlying health conditions by the beginning of March, a target which has also been put back in the face of limited supply.
The reduction in supply was announced in early February, and attributed to Pfizer temporarily suspending manufacturing in order to expand its future capacity.
The total number of doses due to be delivered from Pfizer before the end of March is not expected to change.
Supply has risen in the last week, with 375,050 doses made available to Scotland for order from Public Health England in the week to March 1, compared to 145,080 the week before.