Members of the Royal College of Midwives (RCM) intend to stop work for four hours.
They voted by 9-1 in favour of strike action - the first such vote in the college's 134-year history.
The Department of Health said it was "disappointing" and that it would work with trusts to ensure a safe service was provided to mothers and babies.
It added that its door was always open for discussion.
The RCM is seeking urgent talks with the health minister to resolve the dispute.
RCM NI director Bredagh Hughes said midwives are calling for the 1% pay increase given to their colleagues in Wales, Scotland and England.
"It is very important that women understand that this dispute is not with or about them. It is with the department of health and the employers," she said.
"Not one woman will be put at risk, there will be full emergency cover provided, of course if the midwives on the picket line are called in to make up the numbers, they will do that."
Ms Hughes said clinics and elective work may be disrupted. However she said other forms of industrial action planned from 1 May to 7 May would have an effect.
"The real message will be the following week when midwives start counting the hours they currently work and which they are not paid for and they submit a bill to their employer asking to be paid for the breaks they do not get on a 12 hour shift and the hour or two hours they stay behind and work every day," she said.
"From our experience, we know that every midwife works about three hours unpaid work every single week of their working lives and they have never claimed for that."
Public transport workers have already announced they are to take part in a second strike that will affect all bus and rail services in Northern Ireland.
Unite said that a 24-hour strike was being planned for Wednesday 6 May.
Last month, public transport workers took part in a one-day strike involving education, administration and health service staff.
Unite said the second strike would affect Ulsterbus, Metro and NI Railways services.
In a statement, Translink said it was disappointing that passengers "could be inconvenienced" as a result of the proposed strike action "which comes at a time when many schoolchildren are preparing for or taking exams".
"We are, of course, seeking to urgently meet with Unite to discuss this news that they are to go on strike on 6 May," they said.
Midwives in Northern Ireland have voted to strike on 30 April in a dispute over pay.